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Surgical Lesions of the Pancreas
SURGICAL LESIONS OF THE PANCREAS JAMES
T.
PRIESTLEY
During the past twenty years or so, significant advances have been made in the recognition and treatment of various surgical lesions which arise within the pancreas. Whereas in former years the pancreas was infrequently the primary object of the surgeons' attention, at the present time an increasing number of surgical procedures are performed for various pathologic changes which develop within this gland. Obviously much remains to be accomplished both in diagnosis and surgical treatment despite the advances which have been made. For the most part, the experience of any individual surgeon in the treatment of pancreatic lesions remains rather meager, in contrast with his experience in the treatment of lesions which arise in numerous other abdominal viscera. The present comments cannot include a consideration of all pancreatic lesions, and accordingly they will be limited to a brief discussion of some of the more common ones, namely, pancreatitis, pancreatic cysts, carcinoma and tumors of the islets of Langerhans. PANCREATITIS
During recent years pancreatitis has been reCeIvmg an increasing amount of attention from internists and surgeons alike. As a result, clinical recognition of this disease, the pathologic physiology associated with it, and general therapeutic concepts of this condition have gradually become more clearly appreciated. Acute Pancreatitis. Acute pancreatitis is commonly divided into two types, acute interstitial or edematous pancreatitis, and acute pancreatic necrosis. Various terms have been used to indicate these conditions, particularly the latter one, which has also been called "acute hemorrhagic pancreatitis" or "acute hemorrhagic necrosis of the pancreas." It is considered by many that these are actually different stages or degrees of the same process. Acute pancreatic necrosis occurs most often during middle life, with equal frequency in men and women, and is somewhat more common in the obese or alcoholic patient. Its onset is almost always sudden and is characterized by severe pain in the upper part of the abdomen frequently extending through into the back. Pain persists for a number of hours or days, and commonly is inadequately relieved by the usual doses of morphine. Nausea and vomiting occur promptly as a rule. On initial physical examination findings may be meager and are characterized by a normal or subnormal temperature, a low pulse rate and normal blood pressure. Abdominal tenderness is moderate. Later in the disease, epigastric tenderness is increased and is associated with varying degrees of abdominal rigidity. Distention frequently develops, and shock may supervene. Conclusive laboratory 971
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findings consisting of elevation of the values for serum lipase and amylase are noted in almost all cases, but these changes have also been noted occasionally after the acute perforation of a duodenal ulcer and in association with a few less common conditions. Whereas the treatment of this condition formerly was considered surgical, it is now agreed by most physicians and surgeons that treatment should be medical. Acute edematous pancreatitis presents a similar, though less severe picture, and is likewise treated by medical measures. Acute or subacute recurring or relapsing pancreatitis is now recognized as a clinical entity with increasing frequency. Clinically, it is characterized by recurring episodes of pain in the upper part of the abdomen. The pain is of variable frequency, severity and duration. Whereas early during the course of the disease the painful attacks may occur only once or twice a year, as the disease progresses the frequency of the attacks usually increases and they may occur several times a week or even oftener. The pain is usually situated in the upper half of the abdomen, sometimes more on one side than the other, and is almost always referred into the back. While attacks may last only a few hours, they commonly persist for at least ten hours and may continue for days or several weeks. Large doses of narcotics may be required for their control. Associated sypmtoms are common and characterized by nausea, vomiting, gaseous distention and abdominal tenderness. More or less nondescript gastro-intestinal symptoms may be present during the intervals between attacks or the patient may be relatively free of symptoms at these times. In the experience of my colleagues and myself, significant disease in the biliary tract has been present in approximately half of the cases of relapsing pancreatitis that we have observed. Physical findings are similar in type to those found in cases of acute pancreatic necrosis, but are less pronounced. At times, an enlarged pancreas is palpable. Elevated values for serum amylase and lipase are noted in association with an attack. The value for serum amylase tends to return to normal within one to four days after cessation of pain whereas the value for serum lipase may remain elevated for five to ten days. In case extensive destruction of pancreatic tissue has occurred, these values may not be elevated during an acute attack. An extremely low value for serum calcium during an attack often indicates a serious prognosis. Other chemical abnormalities in the blood may be noted as the result of vomiting and dehydration. There may be an increased concentration of blood sugar, if function of the islet cells is extensively reduced. Various complications may materially alter the clinical picture of the disease. Jaundice may develop because of pressure on the common bile duct by the enlarged, indurated pancreas, but the value for total bilirubin is usually less than 4 or 5 mg. per 100 cc. If extensive damage has occurred to the pancreatic parenchyma because of repeated acute attacks usually over a prolonged period of time, there may be evidence of either external or internal pancreatic insufficiency or both. Steatorrhea is present in the former case and diabetes in the latter. A pseudocyst may
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form during an acute attack and become palpable as the attack subsides. Occasionally, such a cyst appears during an attack and disappears as the attack subsides. Pancreatic calcification may be detected on roentgenologic examination of the pancreatic area if pronounced chronic changes develop within the gla;nd (fig. 260). Under these circumstances, theremaybe only a few areas of calcification or the gland may be studded throughout with calcific deposits of various sizes and shapes. At times, calcareous deposits are present in the pancreatic ducts and may cause varying degrees of obstruction to the free flow of pancreatic juice into
Fig. 260. Calcification of the pancreas.
the duodenum. Ulceration into the stomach, duodenum or colon has been observed, secondary to acute pancreatitis. In fact, subsequent stricture of the colon has been reported in a few cases. Bleeding into the gastro-intestinal tract may occur. In some cases, a peripancreatic abscess may develop and require drainage. Evidence of old pancreatic necrosis is common if operation is performed at a later date. While the cause of acute recurring pancreatitis is somewhat obscure, certain etiologic relationships have been noted. Experimentally, injection of bile into the pancreatic ducts of dogs is usually followed by the development of acute pancreatitis, and it is thought that this mechanism may be responsible for the development of acute pancreatitis in man. Frequently, disease in the biliary tract is associated with pancreatitis
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and regurgitation of opaque media into the pancreatic ducts is often noted when a choledochogram is made through aT-tube in the common bile duct, especially if some degree of obstruction is present in the region of the ampulla of Vater. Clinically, it has been observed repeatedly that many patients who have recurring pancreatitis give a history of the excessive use of alcohol. Trauma, unusual physical exertion and infection have been suggested as having etiologic significance, but in our experience it seems doubtful that these factors are of frequent importance. The treatment of recurring pancreatitis is medical and surgical. While there are no medical measures which exert a significant effect in the prevention of recurrent acute attacks, various types of medical treatment are indicated during the acute attacks and for insufficiency of pancreatic function which may be associated with extensive chronic changes in the gland. During an acute attack, opiates, parenteral administration of fluids and nourishment, and general supportive measures are indicated. In my experience, the antibiotics have not proved to be of great value although they are commonly used. Since acute attacks frequently follow excessive use of alcohol, this should be avoided entirely. Care must be exercised in the use of opiates as drug addiction is not an uncommon complication in severe cases because of the frequency and duration of the pain. Diabetes should be detected, if present and it requires the usual treatment. Excess of fat or nitrogen in .the stool is evidence of deficiency of external pancreatic function and requires dietary control. Often times the use of pancreatin is helpful in the treatment of this complication. Many different surgical procedures have been advocated and tried for the prevention of recurring acute attacks. Simple cholecystectomy was employed in the past with disappointing results. Likewise, cholecystostomy is not usually of much value. Current surgical therapy is largely based on the premis'e that recurrent attacks are caused by a reflux of bile into the pancreatic ducts and therefore an effort is made to remove or obviate any obstruction in the region ·of the ampulla of Vater and prevent any abnormal increase in pressure within the common bile duct. It is my practice at this time to correct any disease within the biliary tract and then to establish prolonged surgical biliary drainage. This is accomplished either by insertion of a large T-tube into the common bile duct or by a sidetracking type of operation such as a choledochoduodenostomy. The former type of external drainage is commonly employed if the common bile duct is not dilated, if the disease is of relatively recent origin, if the changes in the pancreas are not too extensive, and if the patient is young. The T-tube is permitted to remain in place for approximately one year and generally is clamped off entirely except for one hour two or three times a day. In contrast, an interna;l type of biliary drainage is employed when the reverse of these conditions exists. Other procedures, such as dilatation of the ampullary region of the common bile duct and so-called internal sphincterotomy of the sphincter of Oddi, have been used and reported by different surgeons. I have not had
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personal experience with the latter procedure. The former seems to afford only temporary results, and I have suspected that the same might be true of sphincterotomy. The patient with recurring pancreatitis usually experiences certain gradual changes in his symptoms as the disease progresses. Thus, while initially the only important symptoms are those associated with the acute attacks, these may become somewhat less marked as virtually constant pain gradually develops. Between these two extremes there . frequently is a time when the patient has severe attacks which are rather pronounced but, in addition, he has some constant distress between attacks so that, in fact, he is never entirely free of pain. As the clinical picture changes from one of repeated severe attacks to one characterized mainly by constant pain, treatment should be altered accordingly. It is my practice to employ the operative procedures to provide biliary drainage mentioned previously when the main symptoms are caused by recurrent attacks of severe pain but there is no significant pain between attacks. It seems reasonable to suppose that the recurrent attacks are caused by intermittent reflux of bile into the pancreatic duct and that the daily pain is caused by advanced permanent changes of a chronic inflammatory type, in the pancreas which are sufficient to produce sYmptoms. Under these circumstances, little can be done to alter directly the condition of the gland, and the main indication seems to be to relieve the patient of pain. Total pancreatectomy has been performed to accomplish this purpose but this certainly could not be recommended as a routine procedure. In recent years, splanchnicectomy or, at times, a thoracolumbar sympathectomy has been done to relieve pain, with some very satisfactory results. If the pain is predominantly on one side, unilateral operation may prove to be effective, but, in other cases, bilateral operation is required. Experience with this procedure is still limited, but results which are available for evaluation are quite encouraging. There seems to be no need for simultaneous vagotomy as has been recommended by some authors. Concurrent· medical treatment is indicated for pancreatic insufficiency, both external and internal, which so frequently accompany advanced chronic changes in the gland. Evaluation of the role that possible drug addiction may play in the patient's statements regarding his pain must always be carefully considered. In some cases, calculi will be present in the pancreatic ducts and require removal. It is seldom that splanchnic section should ever be done as a primary procedure for chronic pancreatitis unless the clinical evidence is such that the diagnosis can be established beyond any question of a doubt.
CYSTS Numerous classifications of pancreatic cysts are found in the literature. As with most classifications, the simplest one which is accurate and complete from a pathologic point of view is of greatest practical clinical value. The abbreviated classification which follows seems to fulfill most of these
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requirements: pseudocysts, retention cysts, neoplastic cysts, congenital cysts, parasitic cysts and miscellaneous cysts. Pseudocysts. By far the commonest of all pancreatic cysts is not a true cyst, as it has no epithelial lining. Rather, it is a collection of more or less fluid material usually adjacent to, but occasioually within, the pancreas, and is surrounded by a wall of fibrous tissue. It may develop in association with any part of the pancreas and therefore may be situated to the left or right of the midline and either above or below the stomach or duodenum. Occasionally, such a cyst may manifest itself primarily by pressing forward through the transverse mesocolon or in some other unusual site. A pseudocyst may vary in size from several to 30 or more centimeters in diameter. Commonly, it has the appearance of a rounded somewhat indurated cystic mass with a wall several millimeters in thickness. Contents of the cyst vary from a relatively thin, fairly.clear, straw-colored type of fluid to a thick, brownish, viscid collection of heterogeneous consistency. Actual infection, as determined by bacteriologic culture, generally is absent. Variable amounts of pancreatic enzymes may be present in the contents of the cyst or these may be entirely absent. Trauma and pancreatitis are the two most common etiologic factors in the development of pseudocysts. The latter is more frequent than the former. If trauma is the causative factor, it is most often blunt and crushing rather than perforating in type. In a recent review of 44 cases of pseudocyst of the pancreas, evidence of an associated pancreatitis was noted in 21 cases, whereas a significant history of trauma was obtained in only 2 cases. While it is thought that formation of the cyst commonly occurs in association with an acute inflammatory process in the pan" creas, the surgeon may find only chronic changes in the pancreas at the time of operation. In some cases, there is no apparent factor of etiologic significance. In past years a correct preoperative diagnosis of pseudocyst has been made in a relatively small proportion of cases. It would seem that with a clear appreciation of the cause and clinical picture of this lesion and careful study of the patient that a higher degree of accuracy in diagnosis could be established. Although it is commonly stated that pseudocysts occur more often in women than in men, this has not been my experience. Pain is by far the most common symptom of pseudocyst, and is present in 85 per cent of cases. Undoubtedly, the pancreatitis which is so frequently the precursor of, and associated with, the cyst is responsible for a major portion of the pain in many cases. Consequently, the pattern, type and extension of the pain may conform closely to those found in cases of recurring pancreatitis. Pain may occur in any part of the upper half of the abdomen, but frequently is on the left side and referred to the back. Residual soreness is the rule. Gaseous type of dyspepsia is common. 'Physical examination generally reveals recent loss of weight. Jaundice is present in a little less than a third of the cases and depends for its
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occurrence on the site of the cyst, the type and amount of pancreatitis present, and associated calculous disease in the biliary tract. By far the most striking finding on physical examination is a mass in the upper part of the abdomen which is present in approximately 4 of every 5 cases and would probably be found in an even higher percentage except that some of these cysts are relatively small. Physical characteristics of the mass vary. In about half of the cases the cyst is situated primarily to the left of the midline. Generally, it is rounded, slightly tender, relatively immobile, and fairly firm. At times, it may be so firm and fixed that it is mistaken for a neoplasm.
Fig. 261. Widening of the duodenal loop caused by pancreatic cyst.
Laboratory studies may reveal information of diagnostic importance. During an episode of acute pancreatitis, values for serum lipase and amylase may be elevated. Diabetes may be noted owing to extensive destruction of the pancreatic parenchyma incident to associated pancreatitis. Likewise, there may be evidence of external pancreatic insufficiency. A plain roentgenogram of the abdomen may reveal a large soft-tissue shadow, and roentgenologic study of the stomach and duodenum following ingestion of barium may show evidence of displacement of the stomach in one way or another by extrinsic pressure (fig. 261). A cyst in the head of the pancreas may cause marked widening of the normal duodenal loop as visualized roentgenographically. Surgical treatment of a pseudocyst of the pancreas varies depending on the size, situation and physical characteristics of the cyst. The safest, most frequently employed and, in general, the most satisfactory treat-
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ment is marsupialization and drainage. Total eXCISIOn of the cyst is seldom employed unless it is unusually small, because of the absence of a true cyst wall and the fairly dense adherence of the cyst to all surrounding structures. The seriousness of the lesion seldom warrants resection of a portion of the pancreas in association with removal of the cyst. This should never be employed when the cyst is associated with the head of the gland, but in the rare case might be performed when there is a small cyst in the tail of the gland. Anastomosis of this type of cyst to the upper part of the small intestine or stomach is not recommended as a routine procedure, although it has been performed in some cases. When drainage of the cyst is accomplished, the primary indication is to maintain adequate drainage until sufficient time has elapsed to permit complete collapse and obliteration of the cyst. Otherwise, recurrence is likely. The length of time required for this process varies depending on the size of the cyst, the amount of infection that may develop and the quantity of external pancreatic secretion that drains. Usually, it requires a minimum of three or four weeks and may necessitate as many months or even longer. Ultimate and satisfactory healing will occur, in time, in every case unless significant amounts of pancreatic juice drain from the fistulous tract. Treatment of a persistent fistula of this type will be considered in the discussion of retention cysts. Retention Cysts. As the name implies, retention cysts of the pancreas are cysts which contain the products of external pancreatic secretion. These cysts have a true cyst wall which is found to be lined with epithelium, except in the rare case in which this has been Virtually completely obliterated by long standing and increasing pressure within the cyst cavity. It is thought that a cyst of this type may arise as the result of any cause which leads to persisting partial obstruotion of free drainage of external pancreatic secretion from a significant portion of the pancreas. Abrupt, complete occlusion of a pancreatic duct ordinarily results in atrophy of the proximal portion of the pancreas except for that part of the parenchyma which produces the internal pancreatic secretion. Although there are distinct physiologic and pathologic differences between a pseudocyst and a retention cyst, these are the two types of pancreatic cysts which are most likely to be confused at the time of operation. Trauma is perhaps the most frequent cause of a retention cyst but stone or inflammation may be causative factors. In several patients encountered during recent years, what was considered to be pseudocyst associated with pancreatitis was found at the time of operation. The cyst contained rather dark, more or less fluid material of the type frequently found in pseudocysts. One week or so subsequent to marsupialization and drainage of the cyst, the drainage material gradually became more fluid, more profuse and virtually colorless. It then became apparent on chemical analysis of the fluid that was drained that the material which was draining was virtually pure pancreatic juice. Presumably, there was some connection between the cyst and ducts of the pancreas which was not apparent or which did not become fully patent until after preliminary drainage of the cyst.
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When this occurs there are various possibilities in the subsequent care of the patient depending on how long the fistula persists. In a matter of months the fistula may close spontaneously and no further surgical treatment may be necessary. On the other hand, if the fistula persists and large quantities of pancreatic juice drain, one of several procedures may be employed. If the fistulous tract becomes extremely well established, perhaps with the development of a lining of squamous epithelium, * such a tract may be implanted satisfactorily into the stomach. In other cases it may seem advisable to resect the fistulous tract and that portion of the pancreas distal to the site of origin of the fistula. This procedure may be used most satisfactorily of course when the fistula arises near the tail of the gland. Neoplastic Cysts. Various other types of cystic lesions may occur in the pancreas but. are encountered rather infrequently. Probably the most common is benign cystadenoma. Neoplastic cysts commonly produce a palpable tumor, symptoms of pressure, pain, loss of weight and gastro-intestinal symptoms. These cysts may occur in any part of the pancreas but are more commonly found in the body or tail. As. is true of other pancreatic cysts, they are situated above or below the stomach or in other sites depending on the site of development in the pancreas and on the size of the cysts. They may be small or large. Usually, they are of considerable size before attention is directed to their existence. Pathologically, these cysts may vary from a thin-walled unilocular structure to a spongy thick-walled multilocular lesion with a honeycombed appearance on the interior. They may be multiple but usually are single. The lining epithelium may be columnar, cuboidal or mucousproducing, resembling that of intestines. The contents are frequently stained with old blood, but may be clear. Surgical removal is the treatment of choice, as drainage and marsupialization usually results in a permanent fistula or recurrence of the cyst. Cystadenocarcinoma is also found in the pancreas. Symptoms are similar to those of cystadenoma but usually become more pronounced. In fact, cystadenocarcinoma is similar in most ways to benign cystadenoma except for the difference in pathologic picture. Pathologically, the appearance of malignant cystadenoma may vary. It may be partially solid. It usually has a thick wall in most portions, and papillary and sessile projections of malignant tissue extend into the interior of the cyst. Histologically, cystadenocarcinoma commonly is of low grade malignancy. Usually, the malignant process remains intracystic and shows little tendency to invade adjacent structures. The treatment of preference is complete surgical removal. Other neoplastic cysts which are rarely encountered include sarcomatous and teratomatous cysts. At times, there may be cystic degenerations of an ordinary carcinoma of the pancreas. Congenital Cysts. Some cysts of the pancreas, seldom encountered, are considered to be the result of abnormal development. Some of these
* Pancreatic juice as secreted is inactive and thereby exerts no digestive effect on the skin or tissues of the fistulous tracts.
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have been observed in infants. Multiple cysts have been reported and termed "dysontogenetic cysts" to indicate their origin. Polycystic disease, which involves the pancreas and is associated with cysts in the liver, central nervous system, retina and elsewhere, constitutes what is known as von Hippel-Lindau's disease. Dermoid cysts are extremely rare. Cystic fibrosis of the pancreas, first described in 1938, has been recognized more often in recent years and generally is found in infants but it may occur later in life. It sometimes is associated with intestinal obstruction and meconium ileus. Parasitic Cysts. Parasitic cysts of the pancreas are extremely uncommon in this country, but hydatid cysts have been reported. CARCINOMA
The term "carcinoma of the pancreas" commonly refers to a neoplasm which arises from the acinar elements of the gland or occasionally from the ducts. Tumors of the islet of Langerhans are definitely less common and, of course, produce a clinical picture quite in contrast with that which results from an ordinary carcinoma of the pancreas. The usual type of pancreatic neoplasm will be considered first. Although carcinoma of the pancreas has been recognized as a clinical entity for many years, relatively little progress has been made in its diagnosis or treatment. Unfortunately, it often is not recognized until it has existed for some time, since it does not usually produce significant symptoms early in its development. Consequently, it is generally recognized clinically only after there is little opportunity for ultimate cure of the patient. Because of this fact it has presented a most discouraging problem to surgeons and internists alike. The site of development of the carcinoma within the pancreas influences importantly the symptoms which may occur. A growth situated close to the common bile duct may produce recognizable jaundice relatively early in its development, in marked contrast to a lesion which arises in the gland at an appreciable distance from the bile duct. Likewise, a neoplasm which develops immediately adjacent to the duodenum may cause duodenal ulceration which in itself results in bleeding or other symptoms. For some reason which is not entirely clear, carcinoma seems to develop more often in the head and neck of the gland than in the body or tail. In fact, about half of the malignant lesions which develop in the pancreas are situated in head or neck of the gland, approximately a third are classified as diffuse, and the remainder are in the body or tail, according to compilation of reports in the literature. From the point of view of diagnosis it should be emphasized, in contrast with older teachings, that pain is a prominent symptom in the majority of cases of carcinoma of the pancreas. In the reports in the literature the incidence of pain with this lesion varies from approximately 55 to 83 per cent. This refers to the time at which the patient presents himself for diagnosis, since the incidence of pain is even higher late in the course of the disease. Pain is the chief complaint in approximately 3
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of every 4 cases whereas jaundice is the presenting symptom in approximatelyonly 1 of 4 cases. The phrase "painless jaundice" has undoubtedly received too much emphasis in the diagnosis of jaundice as caused by pancreatic neoplasm. Characteristically, the pain associated with carcinoma of the pancreas is dull at the beginning, usually situated toward the middle of the upper part of the abdomen, and commonly referred into the back. The pain gradually becomes more severe and often requires hypodermic medication. It is usually constant and boring in type in . contrast with a typical colic type of pain frequently associated with calculous obstruction in the cystic duct or common bile duct. Gastrointestinal symptoms of varying degree of severity usually develop, anorexia being most common. Loss of weight supervenes. Annoying pruritus occurs almost invariably if jaundice is present. The most common physical findings are loss of weight and the presence of a mass in the upper part of the abdomen. The mass may be caused by the tumor itself, in which event it is usually fixed, firm and not significantly tender. The incidence of jaundice will vary, depending on whether one studies· reports of series of patients subjected to operation or reads reports of the pathologic anatomists. The incidence of jaundice is reported as being higher in the former than in the latter reports. In the presence of jaundice, the gallbladder is distended in the majority of cases and may form a somewhat movable rounded, nontender mass in the right upper quadrant of the abdomen. Enlargement of the liver is a common finding if jaundice is present. Ascites is uncommon, except in faradvanced disease. Laboratory studies are of little positive value in arriving at a diagnosis of carcinoma of the pancreas in many cases but may be of some "negative value," in eliminating other possible conditions as a cause of the patient's symptoms. Some degree of anemia is common. Tests for liver function do not indicate primary parenchymatous hepatic disease. If jaundice is present, the laboratory findings will indicate an obstructive type of jaundice. Duodenal drainage under these circumstances generally is productive of little if any bile, and blood may be detected in the aspirated material. Studies of pancreatic enzymes in the blood usually reveal normal findings. If the pancreatic ducts have been occluded by the neoplasm there may be evidence of external pancreatic insufficiency. Diabetes is uncommon. In a relatively small percentage of cases there may be evidence of external pressure noted on roentgenographic examination of the stomach or duodenum. Occasionally, duodenal ulcer will be diagnosed by the roentgenologist because of secondary involvement of the· duodenum. The surgical treatment of carcinoma of the pancreas presents a discouraging picture at best. Usually, upon exploration of the abdomen, the diagnosis is at once evident upon finding an extremely hard mass in the pancreas. At times, it may be difficult to distinguish carcinoma from pancreatitis by palpation and inspection of the involved area. Ordinary biopsy of an indurated. area or mass in the pancreas is a rather unsatis-
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factory procedure, as a rule, and often does not reveal conclusive evidence as to the nature of the lesion. Biopsy of the mass performed with the Silverman needle may be helpful in this regard, although several specimens may be necessary before a satisfactory one is obtained for diagnosis. Use of this needle permits one to obtain a specimen from a deep portion of the mass without an undue amount of trauma. Negative biopsic findings should not be construed as irrefutable evidence when the gross findings strongly suggest carcinoma. Cure of carcinoma of the pancreas by extirpation of the lesion is seldom possible. In fact, in our experience, only 13 per cent of these lesions have been resected during a recent five-year period. Of the group of cases in which reseclion is performed, there will be only a very small number of patients who survive five years. The operative mortality for resection of the pancreas for carcinoma is of course quite high, ranging perhaps from 12 or 15 per cent to 40 per cent or higher, depending on the experience of the surgeon, selection of patients and other related factors. While the ultimate outlook is extremely poor, even though the lesion is resected, it seems only proper, that here, as elsewhere in the body, the surgeon should endeavor to remove a malignant lesion when possible, if circumstances permit any satisfactory prospect of a successful outcome. Resection of the head of the pancreas for carcinoma, first reported by Whipple as a two-stage procedure in 1935, has been performed in a wide variety of ways. Few surgeons have had an adequate experience with this operation to develop a standarized technic. In my experience, the simplest and most satisfactory manner in which to perform this operation consists of resection of the distal portion of the stomach, the duodenum, head of the pancreas, and distal end of the common bile duct. Gastrointestinal continuity is accomplished by a Polya type of anastomosis between the stomach and jejunum. The jejunum is mobilized at the ligament of Treitz, and the upper end of the jejunum is brought up so as to occupy the position formerly occupied by the duodenum. The cut end of the pancreas is implanted into the jejunum. An end-to-side choledochojejunostomy is then performed a short distance distal to the site of the pancreaticojejunostomy. This procedure is accomplished in one stage ordinarily and has the advantage of relative simplicity, providing drainage of remaining pancreatic secretions into the jejunum and a biliary intestinal anastomosis in what amounts to a defunctionalized loop of jejunum. A resectable neoplastic lesion of the pancreas which does not involve the head of the gland naturally requires a less extensive procedure. Under these circumstances, all of the gland distal to and including the growth is resected and the head of the gland is not disturbed. The resection is commonly performed by working through the gastrocolic omentum. Splenectomy frequently is performed at the same time, eithei to facilitate the operation or as an aid in removing all of the malignant tissue. One should never resect a portion of the pancreas and leave in place a part of the gland distal to the resected portion unless provision
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is made for drainage of external secretion from this portion of the gland into the intestinal tract. When abdominal operation is performed on a patient who has carcinoma of the head of the pancreas which has produced obstructive jaundice, some palliation may usually be afforded the patient even though the lesion is not resected. Generally, this .is accomplished by some form of internal biliary drainage. It is my practice to perform a cholecystojejunostomy in most cases of this type although other types of anastomosis are used at times depending on the findings at operation. External biliary drainage definitely is a procedure of second choice mainly because of the unpleasant features of this procedure from the patient's point of view. Relief of pruritus is almost invariably obtained by an operation which permits adequate drainage of bile, and this in itself affords great relief to the patient. Jaundice tends to improve for at least a time after an operation of this type, and thereby the patient is made more comfortable. However, significant prolongation of life is seldom achieved by any palliative procedure. Probably an average length of life after the diagnosis is established is six or seven months if no palliative surgical treatment is employed, and this usually is not prolonged more than a month or so by a palliative operation. If the neoplastic lesion is situated in the body of the gland rather than in the head, the main objective from a palliative point of view usually is relief of pain rather than relief of jaundice. This presents a somewhat more difficult problem. During recent years, splanchnicectomy, generally unilateral and on the side where there is the greatest amount of pain, has been employed in a few cases with some success, at least until the neoplastic process progresses and involves nerve trunks not severed in this operation. In a very limited number of cases, alcohol has been injected into the splanchnic nerves with some benefit in a few cases. Experience with this procedure has been too limited to comment conclusively at this time on its advantages or hazards; however, some encouraging results have been obtained with its use. TUMORS OF ISLETS OF LANGERHANS
Since the first patient who had a tumor of the islets of Langerhans associated with hyperinsulinism was operated on by W. J. Mayo in 1926, a significant number of cases of this type have been reported. In a few cases, a tumor of the islet cells has been found without associated hypoglycemia; however, cases of this type are definitely the exception rather than the rule and have been reported mainly by pathologists and ordinarily are not of great clinical interest. Clinically the diagnosis of hypoglycemia due to a tumor of the islets of Langerhans can be suspected frequently from the history given by the patient. He will complain usually of "fits," spells of weakness, periodic loss of consciousness or "attacks" which may vary considerably in their severity. Generally, there are sweating, salivation, muscular relaxation or tremors in the early phase. Subsequently, the patient becomes some-
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what disoriented and loses consciousness if the attack progresses. A tonic type of convulsion may ensue, and usually is characterized initially by flexion of the upper extremities with extension of the back and lower extremities. Later, all four extremities are fully extended. All of these symptoms respond promptly to the administration of dextrose. Whipple first described the triad of findings which now are commonly recognized as cardinal features in the diagnosis of hyperfunctioning tumor ,of the islet cells. These are: (1) attacks of nervous or gastro-intestinal disturbances appearing in the fasting state, (2) the attacks are associated with hypoglycemia with values for blood sugar of 50 mg. per 100 cc. or lower, and (3) attacks are relieved promptly by administration of dextrose. The dextrose tolerance test, previously used as a diagnostic procedure is now known to be of no value in the diagnosis. Repeated determinations of the value for the blood sugar in a fasting state constitute the laboratory procedure of most value. Liver function tests should indicate normal hepatic function. Since several patients have been encountered who were malingerers and produced attacks of hypoglycemia with regularity by the self-administration of insulin, this possibility should always be kept in mind. Occasionally, lesions of the central nervous system, liver, pituitary body or suprarenal gland may be confused with tumor of the islet cells but these are uncommon. Pathologically, most tumors of the islet cells are so-called adenomas. Some pathologists consider these to be entirely benign but other pathologists classify the malignancy as grade 1 (method of Broders) because of the histologic picture which they present. Clinically, tumors of this type present no characteristics of malignancy. In a small percentage of cases, probably less than 10 per cent, these adenomas may be multiple. A few cases of adenoma in aberrant pancreatic tissue have been reported. Definitely malignant tumors of the islet cells occur in a small percentage of cases and may give rise to metastasis. These tumors are multiple somewhat more often than the benign adenomas. A condition described as adenomatosis of the islet cells has been reported in a few cases in association with hypoglycemia. In addition, a few cases of hypoglycemia have been reported with no apparent abnormality of the islet cells; however, cases of this type must be viewed with a certain degree of suspicion because of the possibility of an extremely small (smallest reported adenomas known to be associated with hypoglycemia 2.5 mm. in diameter) adenoma that was overlooked in pathologic examination of the pancreas. Medical treatment has never offered a satisfactory solution for the management of a patient who has a hyperfunctioning adenoma of the islets of Langerhans. In the exceptional borderline case of hypoglycemia, medical measures may control the symptoms fairly well; however, in this type of case, probably no true tumor of the islet cells is present. Some patients with a tumor of this type will give a history dating back four or five years or even longer. Usually, however the_history extends over a period of months or perhaps a year or two. Frequently, the pa-
SURGICAL LESIONS OF PANCREAS
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tient has discovered that glucose in some form will relieve his symptoms and has eaten excessively in order to prevent his symptoms. As a result, many of the patients are quite obese when they present themselves for operation, which of course adds to the difficulty of the surgical procedure. The surgical treatment of tumor of the islet cells associated with hypoglycemia may be very satisfactory if a relatively small functioning adenoma is found in an easily accessible portion of the gland. On the other hand, it may be much less satisfactory if no tumor is found or if an extensive neoplastic process is encountered. In the majority of cases, however, an adenoma is found and removed, along with a variable amount of the pancreas, and the patient enjoys a very satisfactory postoperative result. The abdominal incision which has been most satisfactory for exploration of the pancreas, in my experience, is a slightly curved transverse incision, with the convexity directed upward and placed approximately midway between the tip of the xiphoid and the umbilicus. The pancreas is then approached usually through the gastrocolic omentum by retracting the stomach anteriorly and upward. Some small adenomas of the islet cells have virtually the same consistency and color as normal pancreatic tissue, which may make their recognition difficult. This is especially true if the lesion is situated within the parenchyma of the gland so that it is not visible on the surface. Fortunately, most adenomas have a somewhat greater consistency than normal pancreatic tissue and also a deeper color, varying from a dark yellow to a brownish color. It is a good plan to explore carefully the entire pancreas as an initial procedure, since, even though a tumor is apparent, one must remember that multiple lesions may be expected in perhaps 10 per cent of cases in which the tumor is benign and somewhat oftener in cases in which a malignant lesion is present. Lateral mobilization of the duodenum aids in adequate inspection and palpation of the head of the pancreas. Only about 20 to 25 per cent of adenomas are found in the head of the gland, the remainder being in the body or tail, which, of course, is fortunate so far as removal of these lesions is concerned. If one finds a relatively small encapsulated tumor which can be removed by local excision, this is the simplest procedure and ordinarily can be accomplished in a satisfactory manner. At times, it may be necessary to resect a portion of the pancreas in order to remove the tumor. If this is done, resection of the pancreas should be started at the tail and carried toward the head of the gland until one has progressed far enough to include the tumor in the resected portion of pancreas. The remaining end of the pancreas is then sutured with catgut or silk. Resection of the pancreas so that a portion of the gland is left distally, disconnected from the rest of the pancreas, is inadvisable. The type of case which offers the most difficult problem is the one in which careful exploration of the entire pancreas reveals no tumor. This, of course, does not mean that there is no tumor present but merely that the surgeon is unable to locate a tumor. It has been my practice in 2
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recent years to resect approximately two thirds to three quarters of the pancreas in cases of this type, starting the resection distally at the tail and bringing it toward the head of the gland, usually a short distance to the right of the superior mesenteric vessels. In our experience at the Clinic, a good result may be anticipated if there is a tumor in the resected portion of the pancreas. In 1 case observed at the Clinic, the tumor was so small and so difficult to discover that it was not detected until several months after the operation, when the gland was carefully reexamined because the patient was apparently well. If no tumor is found in the resected portion of the pancreas, a favorable result is not expected, although exceptions to this rule have been reported. Usually, however, it is necessary to resect more pancreatic tissue at a subsequent operation. In the experimental animal it is necessary to resect at least 90 per cent of the pancreas in order to produce diabetes, and clinical evidence suggests a similar situation in man. A second resection is most likely to be successful in relieving the patient if a tumor is found in the resected portion. A search for ectopic pancreatic tissue is always advisable when no tumor is found in the pancreas. Although total pancreatectomy has been performed as a primary procedure in a case of hyperinsulinism in which no tumor could be found, this is not a recommended procedure. A check on the value of the fasting blood sugar at a suitable interval after operation affords evidence relative to the success of the operation.
T.
PRIESTLEY
During the past twenty years or so, significant advances have been made in the recognition and treatment of various surgical lesions which arise within the pancreas. Whereas in former years the pancreas was infrequently the primary object of the surgeons' attention, at the present time an increasing number of surgical procedures are performed for various pathologic changes which develop within this gland. Obviously much remains to be accomplished both in diagnosis and surgical treatment despite the advances which have been made. For the most part, the experience of any individual surgeon in the treatment of pancreatic lesions remains rather meager, in contrast with his experience in the treatment of lesions which arise in numerous other abdominal viscera. The present comments cannot include a consideration of all pancreatic lesions, and accordingly they will be limited to a brief discussion of some of the more common ones, namely, pancreatitis, pancreatic cysts, carcinoma and tumors of the islets of Langerhans. PANCREATITIS
During recent years pancreatitis has been reCeIvmg an increasing amount of attention from internists and surgeons alike. As a result, clinical recognition of this disease, the pathologic physiology associated with it, and general therapeutic concepts of this condition have gradually become more clearly appreciated. Acute Pancreatitis. Acute pancreatitis is commonly divided into two types, acute interstitial or edematous pancreatitis, and acute pancreatic necrosis. Various terms have been used to indicate these conditions, particularly the latter one, which has also been called "acute hemorrhagic pancreatitis" or "acute hemorrhagic necrosis of the pancreas." It is considered by many that these are actually different stages or degrees of the same process. Acute pancreatic necrosis occurs most often during middle life, with equal frequency in men and women, and is somewhat more common in the obese or alcoholic patient. Its onset is almost always sudden and is characterized by severe pain in the upper part of the abdomen frequently extending through into the back. Pain persists for a number of hours or days, and commonly is inadequately relieved by the usual doses of morphine. Nausea and vomiting occur promptly as a rule. On initial physical examination findings may be meager and are characterized by a normal or subnormal temperature, a low pulse rate and normal blood pressure. Abdominal tenderness is moderate. Later in the disease, epigastric tenderness is increased and is associated with varying degrees of abdominal rigidity. Distention frequently develops, and shock may supervene. Conclusive laboratory 971
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findings consisting of elevation of the values for serum lipase and amylase are noted in almost all cases, but these changes have also been noted occasionally after the acute perforation of a duodenal ulcer and in association with a few less common conditions. Whereas the treatment of this condition formerly was considered surgical, it is now agreed by most physicians and surgeons that treatment should be medical. Acute edematous pancreatitis presents a similar, though less severe picture, and is likewise treated by medical measures. Acute or subacute recurring or relapsing pancreatitis is now recognized as a clinical entity with increasing frequency. Clinically, it is characterized by recurring episodes of pain in the upper part of the abdomen. The pain is of variable frequency, severity and duration. Whereas early during the course of the disease the painful attacks may occur only once or twice a year, as the disease progresses the frequency of the attacks usually increases and they may occur several times a week or even oftener. The pain is usually situated in the upper half of the abdomen, sometimes more on one side than the other, and is almost always referred into the back. While attacks may last only a few hours, they commonly persist for at least ten hours and may continue for days or several weeks. Large doses of narcotics may be required for their control. Associated sypmtoms are common and characterized by nausea, vomiting, gaseous distention and abdominal tenderness. More or less nondescript gastro-intestinal symptoms may be present during the intervals between attacks or the patient may be relatively free of symptoms at these times. In the experience of my colleagues and myself, significant disease in the biliary tract has been present in approximately half of the cases of relapsing pancreatitis that we have observed. Physical findings are similar in type to those found in cases of acute pancreatic necrosis, but are less pronounced. At times, an enlarged pancreas is palpable. Elevated values for serum amylase and lipase are noted in association with an attack. The value for serum amylase tends to return to normal within one to four days after cessation of pain whereas the value for serum lipase may remain elevated for five to ten days. In case extensive destruction of pancreatic tissue has occurred, these values may not be elevated during an acute attack. An extremely low value for serum calcium during an attack often indicates a serious prognosis. Other chemical abnormalities in the blood may be noted as the result of vomiting and dehydration. There may be an increased concentration of blood sugar, if function of the islet cells is extensively reduced. Various complications may materially alter the clinical picture of the disease. Jaundice may develop because of pressure on the common bile duct by the enlarged, indurated pancreas, but the value for total bilirubin is usually less than 4 or 5 mg. per 100 cc. If extensive damage has occurred to the pancreatic parenchyma because of repeated acute attacks usually over a prolonged period of time, there may be evidence of either external or internal pancreatic insufficiency or both. Steatorrhea is present in the former case and diabetes in the latter. A pseudocyst may
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form during an acute attack and become palpable as the attack subsides. Occasionally, such a cyst appears during an attack and disappears as the attack subsides. Pancreatic calcification may be detected on roentgenologic examination of the pancreatic area if pronounced chronic changes develop within the gla;nd (fig. 260). Under these circumstances, theremaybe only a few areas of calcification or the gland may be studded throughout with calcific deposits of various sizes and shapes. At times, calcareous deposits are present in the pancreatic ducts and may cause varying degrees of obstruction to the free flow of pancreatic juice into
Fig. 260. Calcification of the pancreas.
the duodenum. Ulceration into the stomach, duodenum or colon has been observed, secondary to acute pancreatitis. In fact, subsequent stricture of the colon has been reported in a few cases. Bleeding into the gastro-intestinal tract may occur. In some cases, a peripancreatic abscess may develop and require drainage. Evidence of old pancreatic necrosis is common if operation is performed at a later date. While the cause of acute recurring pancreatitis is somewhat obscure, certain etiologic relationships have been noted. Experimentally, injection of bile into the pancreatic ducts of dogs is usually followed by the development of acute pancreatitis, and it is thought that this mechanism may be responsible for the development of acute pancreatitis in man. Frequently, disease in the biliary tract is associated with pancreatitis
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JAMES T. PRIESTLEY
and regurgitation of opaque media into the pancreatic ducts is often noted when a choledochogram is made through aT-tube in the common bile duct, especially if some degree of obstruction is present in the region of the ampulla of Vater. Clinically, it has been observed repeatedly that many patients who have recurring pancreatitis give a history of the excessive use of alcohol. Trauma, unusual physical exertion and infection have been suggested as having etiologic significance, but in our experience it seems doubtful that these factors are of frequent importance. The treatment of recurring pancreatitis is medical and surgical. While there are no medical measures which exert a significant effect in the prevention of recurrent acute attacks, various types of medical treatment are indicated during the acute attacks and for insufficiency of pancreatic function which may be associated with extensive chronic changes in the gland. During an acute attack, opiates, parenteral administration of fluids and nourishment, and general supportive measures are indicated. In my experience, the antibiotics have not proved to be of great value although they are commonly used. Since acute attacks frequently follow excessive use of alcohol, this should be avoided entirely. Care must be exercised in the use of opiates as drug addiction is not an uncommon complication in severe cases because of the frequency and duration of the pain. Diabetes should be detected, if present and it requires the usual treatment. Excess of fat or nitrogen in .the stool is evidence of deficiency of external pancreatic function and requires dietary control. Often times the use of pancreatin is helpful in the treatment of this complication. Many different surgical procedures have been advocated and tried for the prevention of recurring acute attacks. Simple cholecystectomy was employed in the past with disappointing results. Likewise, cholecystostomy is not usually of much value. Current surgical therapy is largely based on the premis'e that recurrent attacks are caused by a reflux of bile into the pancreatic ducts and therefore an effort is made to remove or obviate any obstruction in the region ·of the ampulla of Vater and prevent any abnormal increase in pressure within the common bile duct. It is my practice at this time to correct any disease within the biliary tract and then to establish prolonged surgical biliary drainage. This is accomplished either by insertion of a large T-tube into the common bile duct or by a sidetracking type of operation such as a choledochoduodenostomy. The former type of external drainage is commonly employed if the common bile duct is not dilated, if the disease is of relatively recent origin, if the changes in the pancreas are not too extensive, and if the patient is young. The T-tube is permitted to remain in place for approximately one year and generally is clamped off entirely except for one hour two or three times a day. In contrast, an interna;l type of biliary drainage is employed when the reverse of these conditions exists. Other procedures, such as dilatation of the ampullary region of the common bile duct and so-called internal sphincterotomy of the sphincter of Oddi, have been used and reported by different surgeons. I have not had
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personal experience with the latter procedure. The former seems to afford only temporary results, and I have suspected that the same might be true of sphincterotomy. The patient with recurring pancreatitis usually experiences certain gradual changes in his symptoms as the disease progresses. Thus, while initially the only important symptoms are those associated with the acute attacks, these may become somewhat less marked as virtually constant pain gradually develops. Between these two extremes there . frequently is a time when the patient has severe attacks which are rather pronounced but, in addition, he has some constant distress between attacks so that, in fact, he is never entirely free of pain. As the clinical picture changes from one of repeated severe attacks to one characterized mainly by constant pain, treatment should be altered accordingly. It is my practice to employ the operative procedures to provide biliary drainage mentioned previously when the main symptoms are caused by recurrent attacks of severe pain but there is no significant pain between attacks. It seems reasonable to suppose that the recurrent attacks are caused by intermittent reflux of bile into the pancreatic duct and that the daily pain is caused by advanced permanent changes of a chronic inflammatory type, in the pancreas which are sufficient to produce sYmptoms. Under these circumstances, little can be done to alter directly the condition of the gland, and the main indication seems to be to relieve the patient of pain. Total pancreatectomy has been performed to accomplish this purpose but this certainly could not be recommended as a routine procedure. In recent years, splanchnicectomy or, at times, a thoracolumbar sympathectomy has been done to relieve pain, with some very satisfactory results. If the pain is predominantly on one side, unilateral operation may prove to be effective, but, in other cases, bilateral operation is required. Experience with this procedure is still limited, but results which are available for evaluation are quite encouraging. There seems to be no need for simultaneous vagotomy as has been recommended by some authors. Concurrent· medical treatment is indicated for pancreatic insufficiency, both external and internal, which so frequently accompany advanced chronic changes in the gland. Evaluation of the role that possible drug addiction may play in the patient's statements regarding his pain must always be carefully considered. In some cases, calculi will be present in the pancreatic ducts and require removal. It is seldom that splanchnic section should ever be done as a primary procedure for chronic pancreatitis unless the clinical evidence is such that the diagnosis can be established beyond any question of a doubt.
CYSTS Numerous classifications of pancreatic cysts are found in the literature. As with most classifications, the simplest one which is accurate and complete from a pathologic point of view is of greatest practical clinical value. The abbreviated classification which follows seems to fulfill most of these
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requirements: pseudocysts, retention cysts, neoplastic cysts, congenital cysts, parasitic cysts and miscellaneous cysts. Pseudocysts. By far the commonest of all pancreatic cysts is not a true cyst, as it has no epithelial lining. Rather, it is a collection of more or less fluid material usually adjacent to, but occasioually within, the pancreas, and is surrounded by a wall of fibrous tissue. It may develop in association with any part of the pancreas and therefore may be situated to the left or right of the midline and either above or below the stomach or duodenum. Occasionally, such a cyst may manifest itself primarily by pressing forward through the transverse mesocolon or in some other unusual site. A pseudocyst may vary in size from several to 30 or more centimeters in diameter. Commonly, it has the appearance of a rounded somewhat indurated cystic mass with a wall several millimeters in thickness. Contents of the cyst vary from a relatively thin, fairly.clear, straw-colored type of fluid to a thick, brownish, viscid collection of heterogeneous consistency. Actual infection, as determined by bacteriologic culture, generally is absent. Variable amounts of pancreatic enzymes may be present in the contents of the cyst or these may be entirely absent. Trauma and pancreatitis are the two most common etiologic factors in the development of pseudocysts. The latter is more frequent than the former. If trauma is the causative factor, it is most often blunt and crushing rather than perforating in type. In a recent review of 44 cases of pseudocyst of the pancreas, evidence of an associated pancreatitis was noted in 21 cases, whereas a significant history of trauma was obtained in only 2 cases. While it is thought that formation of the cyst commonly occurs in association with an acute inflammatory process in the pan" creas, the surgeon may find only chronic changes in the pancreas at the time of operation. In some cases, there is no apparent factor of etiologic significance. In past years a correct preoperative diagnosis of pseudocyst has been made in a relatively small proportion of cases. It would seem that with a clear appreciation of the cause and clinical picture of this lesion and careful study of the patient that a higher degree of accuracy in diagnosis could be established. Although it is commonly stated that pseudocysts occur more often in women than in men, this has not been my experience. Pain is by far the most common symptom of pseudocyst, and is present in 85 per cent of cases. Undoubtedly, the pancreatitis which is so frequently the precursor of, and associated with, the cyst is responsible for a major portion of the pain in many cases. Consequently, the pattern, type and extension of the pain may conform closely to those found in cases of recurring pancreatitis. Pain may occur in any part of the upper half of the abdomen, but frequently is on the left side and referred to the back. Residual soreness is the rule. Gaseous type of dyspepsia is common. 'Physical examination generally reveals recent loss of weight. Jaundice is present in a little less than a third of the cases and depends for its
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occurrence on the site of the cyst, the type and amount of pancreatitis present, and associated calculous disease in the biliary tract. By far the most striking finding on physical examination is a mass in the upper part of the abdomen which is present in approximately 4 of every 5 cases and would probably be found in an even higher percentage except that some of these cysts are relatively small. Physical characteristics of the mass vary. In about half of the cases the cyst is situated primarily to the left of the midline. Generally, it is rounded, slightly tender, relatively immobile, and fairly firm. At times, it may be so firm and fixed that it is mistaken for a neoplasm.
Fig. 261. Widening of the duodenal loop caused by pancreatic cyst.
Laboratory studies may reveal information of diagnostic importance. During an episode of acute pancreatitis, values for serum lipase and amylase may be elevated. Diabetes may be noted owing to extensive destruction of the pancreatic parenchyma incident to associated pancreatitis. Likewise, there may be evidence of external pancreatic insufficiency. A plain roentgenogram of the abdomen may reveal a large soft-tissue shadow, and roentgenologic study of the stomach and duodenum following ingestion of barium may show evidence of displacement of the stomach in one way or another by extrinsic pressure (fig. 261). A cyst in the head of the pancreas may cause marked widening of the normal duodenal loop as visualized roentgenographically. Surgical treatment of a pseudocyst of the pancreas varies depending on the size, situation and physical characteristics of the cyst. The safest, most frequently employed and, in general, the most satisfactory treat-
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JAMES T. PRIESTLEY
ment is marsupialization and drainage. Total eXCISIOn of the cyst is seldom employed unless it is unusually small, because of the absence of a true cyst wall and the fairly dense adherence of the cyst to all surrounding structures. The seriousness of the lesion seldom warrants resection of a portion of the pancreas in association with removal of the cyst. This should never be employed when the cyst is associated with the head of the gland, but in the rare case might be performed when there is a small cyst in the tail of the gland. Anastomosis of this type of cyst to the upper part of the small intestine or stomach is not recommended as a routine procedure, although it has been performed in some cases. When drainage of the cyst is accomplished, the primary indication is to maintain adequate drainage until sufficient time has elapsed to permit complete collapse and obliteration of the cyst. Otherwise, recurrence is likely. The length of time required for this process varies depending on the size of the cyst, the amount of infection that may develop and the quantity of external pancreatic secretion that drains. Usually, it requires a minimum of three or four weeks and may necessitate as many months or even longer. Ultimate and satisfactory healing will occur, in time, in every case unless significant amounts of pancreatic juice drain from the fistulous tract. Treatment of a persistent fistula of this type will be considered in the discussion of retention cysts. Retention Cysts. As the name implies, retention cysts of the pancreas are cysts which contain the products of external pancreatic secretion. These cysts have a true cyst wall which is found to be lined with epithelium, except in the rare case in which this has been Virtually completely obliterated by long standing and increasing pressure within the cyst cavity. It is thought that a cyst of this type may arise as the result of any cause which leads to persisting partial obstruotion of free drainage of external pancreatic secretion from a significant portion of the pancreas. Abrupt, complete occlusion of a pancreatic duct ordinarily results in atrophy of the proximal portion of the pancreas except for that part of the parenchyma which produces the internal pancreatic secretion. Although there are distinct physiologic and pathologic differences between a pseudocyst and a retention cyst, these are the two types of pancreatic cysts which are most likely to be confused at the time of operation. Trauma is perhaps the most frequent cause of a retention cyst but stone or inflammation may be causative factors. In several patients encountered during recent years, what was considered to be pseudocyst associated with pancreatitis was found at the time of operation. The cyst contained rather dark, more or less fluid material of the type frequently found in pseudocysts. One week or so subsequent to marsupialization and drainage of the cyst, the drainage material gradually became more fluid, more profuse and virtually colorless. It then became apparent on chemical analysis of the fluid that was drained that the material which was draining was virtually pure pancreatic juice. Presumably, there was some connection between the cyst and ducts of the pancreas which was not apparent or which did not become fully patent until after preliminary drainage of the cyst.
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When this occurs there are various possibilities in the subsequent care of the patient depending on how long the fistula persists. In a matter of months the fistula may close spontaneously and no further surgical treatment may be necessary. On the other hand, if the fistula persists and large quantities of pancreatic juice drain, one of several procedures may be employed. If the fistulous tract becomes extremely well established, perhaps with the development of a lining of squamous epithelium, * such a tract may be implanted satisfactorily into the stomach. In other cases it may seem advisable to resect the fistulous tract and that portion of the pancreas distal to the site of origin of the fistula. This procedure may be used most satisfactorily of course when the fistula arises near the tail of the gland. Neoplastic Cysts. Various other types of cystic lesions may occur in the pancreas but. are encountered rather infrequently. Probably the most common is benign cystadenoma. Neoplastic cysts commonly produce a palpable tumor, symptoms of pressure, pain, loss of weight and gastro-intestinal symptoms. These cysts may occur in any part of the pancreas but are more commonly found in the body or tail. As. is true of other pancreatic cysts, they are situated above or below the stomach or in other sites depending on the site of development in the pancreas and on the size of the cysts. They may be small or large. Usually, they are of considerable size before attention is directed to their existence. Pathologically, these cysts may vary from a thin-walled unilocular structure to a spongy thick-walled multilocular lesion with a honeycombed appearance on the interior. They may be multiple but usually are single. The lining epithelium may be columnar, cuboidal or mucousproducing, resembling that of intestines. The contents are frequently stained with old blood, but may be clear. Surgical removal is the treatment of choice, as drainage and marsupialization usually results in a permanent fistula or recurrence of the cyst. Cystadenocarcinoma is also found in the pancreas. Symptoms are similar to those of cystadenoma but usually become more pronounced. In fact, cystadenocarcinoma is similar in most ways to benign cystadenoma except for the difference in pathologic picture. Pathologically, the appearance of malignant cystadenoma may vary. It may be partially solid. It usually has a thick wall in most portions, and papillary and sessile projections of malignant tissue extend into the interior of the cyst. Histologically, cystadenocarcinoma commonly is of low grade malignancy. Usually, the malignant process remains intracystic and shows little tendency to invade adjacent structures. The treatment of preference is complete surgical removal. Other neoplastic cysts which are rarely encountered include sarcomatous and teratomatous cysts. At times, there may be cystic degenerations of an ordinary carcinoma of the pancreas. Congenital Cysts. Some cysts of the pancreas, seldom encountered, are considered to be the result of abnormal development. Some of these
* Pancreatic juice as secreted is inactive and thereby exerts no digestive effect on the skin or tissues of the fistulous tracts.
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JAMES T. PRIESTLEY
have been observed in infants. Multiple cysts have been reported and termed "dysontogenetic cysts" to indicate their origin. Polycystic disease, which involves the pancreas and is associated with cysts in the liver, central nervous system, retina and elsewhere, constitutes what is known as von Hippel-Lindau's disease. Dermoid cysts are extremely rare. Cystic fibrosis of the pancreas, first described in 1938, has been recognized more often in recent years and generally is found in infants but it may occur later in life. It sometimes is associated with intestinal obstruction and meconium ileus. Parasitic Cysts. Parasitic cysts of the pancreas are extremely uncommon in this country, but hydatid cysts have been reported. CARCINOMA
The term "carcinoma of the pancreas" commonly refers to a neoplasm which arises from the acinar elements of the gland or occasionally from the ducts. Tumors of the islet of Langerhans are definitely less common and, of course, produce a clinical picture quite in contrast with that which results from an ordinary carcinoma of the pancreas. The usual type of pancreatic neoplasm will be considered first. Although carcinoma of the pancreas has been recognized as a clinical entity for many years, relatively little progress has been made in its diagnosis or treatment. Unfortunately, it often is not recognized until it has existed for some time, since it does not usually produce significant symptoms early in its development. Consequently, it is generally recognized clinically only after there is little opportunity for ultimate cure of the patient. Because of this fact it has presented a most discouraging problem to surgeons and internists alike. The site of development of the carcinoma within the pancreas influences importantly the symptoms which may occur. A growth situated close to the common bile duct may produce recognizable jaundice relatively early in its development, in marked contrast to a lesion which arises in the gland at an appreciable distance from the bile duct. Likewise, a neoplasm which develops immediately adjacent to the duodenum may cause duodenal ulceration which in itself results in bleeding or other symptoms. For some reason which is not entirely clear, carcinoma seems to develop more often in the head and neck of the gland than in the body or tail. In fact, about half of the malignant lesions which develop in the pancreas are situated in head or neck of the gland, approximately a third are classified as diffuse, and the remainder are in the body or tail, according to compilation of reports in the literature. From the point of view of diagnosis it should be emphasized, in contrast with older teachings, that pain is a prominent symptom in the majority of cases of carcinoma of the pancreas. In the reports in the literature the incidence of pain with this lesion varies from approximately 55 to 83 per cent. This refers to the time at which the patient presents himself for diagnosis, since the incidence of pain is even higher late in the course of the disease. Pain is the chief complaint in approximately 3
SURGICAL LESIONS OF PANCREAS
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of every 4 cases whereas jaundice is the presenting symptom in approximatelyonly 1 of 4 cases. The phrase "painless jaundice" has undoubtedly received too much emphasis in the diagnosis of jaundice as caused by pancreatic neoplasm. Characteristically, the pain associated with carcinoma of the pancreas is dull at the beginning, usually situated toward the middle of the upper part of the abdomen, and commonly referred into the back. The pain gradually becomes more severe and often requires hypodermic medication. It is usually constant and boring in type in . contrast with a typical colic type of pain frequently associated with calculous obstruction in the cystic duct or common bile duct. Gastrointestinal symptoms of varying degree of severity usually develop, anorexia being most common. Loss of weight supervenes. Annoying pruritus occurs almost invariably if jaundice is present. The most common physical findings are loss of weight and the presence of a mass in the upper part of the abdomen. The mass may be caused by the tumor itself, in which event it is usually fixed, firm and not significantly tender. The incidence of jaundice will vary, depending on whether one studies· reports of series of patients subjected to operation or reads reports of the pathologic anatomists. The incidence of jaundice is reported as being higher in the former than in the latter reports. In the presence of jaundice, the gallbladder is distended in the majority of cases and may form a somewhat movable rounded, nontender mass in the right upper quadrant of the abdomen. Enlargement of the liver is a common finding if jaundice is present. Ascites is uncommon, except in faradvanced disease. Laboratory studies are of little positive value in arriving at a diagnosis of carcinoma of the pancreas in many cases but may be of some "negative value," in eliminating other possible conditions as a cause of the patient's symptoms. Some degree of anemia is common. Tests for liver function do not indicate primary parenchymatous hepatic disease. If jaundice is present, the laboratory findings will indicate an obstructive type of jaundice. Duodenal drainage under these circumstances generally is productive of little if any bile, and blood may be detected in the aspirated material. Studies of pancreatic enzymes in the blood usually reveal normal findings. If the pancreatic ducts have been occluded by the neoplasm there may be evidence of external pancreatic insufficiency. Diabetes is uncommon. In a relatively small percentage of cases there may be evidence of external pressure noted on roentgenographic examination of the stomach or duodenum. Occasionally, duodenal ulcer will be diagnosed by the roentgenologist because of secondary involvement of the· duodenum. The surgical treatment of carcinoma of the pancreas presents a discouraging picture at best. Usually, upon exploration of the abdomen, the diagnosis is at once evident upon finding an extremely hard mass in the pancreas. At times, it may be difficult to distinguish carcinoma from pancreatitis by palpation and inspection of the involved area. Ordinary biopsy of an indurated. area or mass in the pancreas is a rather unsatis-
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factory procedure, as a rule, and often does not reveal conclusive evidence as to the nature of the lesion. Biopsy of the mass performed with the Silverman needle may be helpful in this regard, although several specimens may be necessary before a satisfactory one is obtained for diagnosis. Use of this needle permits one to obtain a specimen from a deep portion of the mass without an undue amount of trauma. Negative biopsic findings should not be construed as irrefutable evidence when the gross findings strongly suggest carcinoma. Cure of carcinoma of the pancreas by extirpation of the lesion is seldom possible. In fact, in our experience, only 13 per cent of these lesions have been resected during a recent five-year period. Of the group of cases in which reseclion is performed, there will be only a very small number of patients who survive five years. The operative mortality for resection of the pancreas for carcinoma is of course quite high, ranging perhaps from 12 or 15 per cent to 40 per cent or higher, depending on the experience of the surgeon, selection of patients and other related factors. While the ultimate outlook is extremely poor, even though the lesion is resected, it seems only proper, that here, as elsewhere in the body, the surgeon should endeavor to remove a malignant lesion when possible, if circumstances permit any satisfactory prospect of a successful outcome. Resection of the head of the pancreas for carcinoma, first reported by Whipple as a two-stage procedure in 1935, has been performed in a wide variety of ways. Few surgeons have had an adequate experience with this operation to develop a standarized technic. In my experience, the simplest and most satisfactory manner in which to perform this operation consists of resection of the distal portion of the stomach, the duodenum, head of the pancreas, and distal end of the common bile duct. Gastrointestinal continuity is accomplished by a Polya type of anastomosis between the stomach and jejunum. The jejunum is mobilized at the ligament of Treitz, and the upper end of the jejunum is brought up so as to occupy the position formerly occupied by the duodenum. The cut end of the pancreas is implanted into the jejunum. An end-to-side choledochojejunostomy is then performed a short distance distal to the site of the pancreaticojejunostomy. This procedure is accomplished in one stage ordinarily and has the advantage of relative simplicity, providing drainage of remaining pancreatic secretions into the jejunum and a biliary intestinal anastomosis in what amounts to a defunctionalized loop of jejunum. A resectable neoplastic lesion of the pancreas which does not involve the head of the gland naturally requires a less extensive procedure. Under these circumstances, all of the gland distal to and including the growth is resected and the head of the gland is not disturbed. The resection is commonly performed by working through the gastrocolic omentum. Splenectomy frequently is performed at the same time, eithei to facilitate the operation or as an aid in removing all of the malignant tissue. One should never resect a portion of the pancreas and leave in place a part of the gland distal to the resected portion unless provision
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is made for drainage of external secretion from this portion of the gland into the intestinal tract. When abdominal operation is performed on a patient who has carcinoma of the head of the pancreas which has produced obstructive jaundice, some palliation may usually be afforded the patient even though the lesion is not resected. Generally, this .is accomplished by some form of internal biliary drainage. It is my practice to perform a cholecystojejunostomy in most cases of this type although other types of anastomosis are used at times depending on the findings at operation. External biliary drainage definitely is a procedure of second choice mainly because of the unpleasant features of this procedure from the patient's point of view. Relief of pruritus is almost invariably obtained by an operation which permits adequate drainage of bile, and this in itself affords great relief to the patient. Jaundice tends to improve for at least a time after an operation of this type, and thereby the patient is made more comfortable. However, significant prolongation of life is seldom achieved by any palliative procedure. Probably an average length of life after the diagnosis is established is six or seven months if no palliative surgical treatment is employed, and this usually is not prolonged more than a month or so by a palliative operation. If the neoplastic lesion is situated in the body of the gland rather than in the head, the main objective from a palliative point of view usually is relief of pain rather than relief of jaundice. This presents a somewhat more difficult problem. During recent years, splanchnicectomy, generally unilateral and on the side where there is the greatest amount of pain, has been employed in a few cases with some success, at least until the neoplastic process progresses and involves nerve trunks not severed in this operation. In a very limited number of cases, alcohol has been injected into the splanchnic nerves with some benefit in a few cases. Experience with this procedure has been too limited to comment conclusively at this time on its advantages or hazards; however, some encouraging results have been obtained with its use. TUMORS OF ISLETS OF LANGERHANS
Since the first patient who had a tumor of the islets of Langerhans associated with hyperinsulinism was operated on by W. J. Mayo in 1926, a significant number of cases of this type have been reported. In a few cases, a tumor of the islet cells has been found without associated hypoglycemia; however, cases of this type are definitely the exception rather than the rule and have been reported mainly by pathologists and ordinarily are not of great clinical interest. Clinically the diagnosis of hypoglycemia due to a tumor of the islets of Langerhans can be suspected frequently from the history given by the patient. He will complain usually of "fits," spells of weakness, periodic loss of consciousness or "attacks" which may vary considerably in their severity. Generally, there are sweating, salivation, muscular relaxation or tremors in the early phase. Subsequently, the patient becomes some-
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what disoriented and loses consciousness if the attack progresses. A tonic type of convulsion may ensue, and usually is characterized initially by flexion of the upper extremities with extension of the back and lower extremities. Later, all four extremities are fully extended. All of these symptoms respond promptly to the administration of dextrose. Whipple first described the triad of findings which now are commonly recognized as cardinal features in the diagnosis of hyperfunctioning tumor ,of the islet cells. These are: (1) attacks of nervous or gastro-intestinal disturbances appearing in the fasting state, (2) the attacks are associated with hypoglycemia with values for blood sugar of 50 mg. per 100 cc. or lower, and (3) attacks are relieved promptly by administration of dextrose. The dextrose tolerance test, previously used as a diagnostic procedure is now known to be of no value in the diagnosis. Repeated determinations of the value for the blood sugar in a fasting state constitute the laboratory procedure of most value. Liver function tests should indicate normal hepatic function. Since several patients have been encountered who were malingerers and produced attacks of hypoglycemia with regularity by the self-administration of insulin, this possibility should always be kept in mind. Occasionally, lesions of the central nervous system, liver, pituitary body or suprarenal gland may be confused with tumor of the islet cells but these are uncommon. Pathologically, most tumors of the islet cells are so-called adenomas. Some pathologists consider these to be entirely benign but other pathologists classify the malignancy as grade 1 (method of Broders) because of the histologic picture which they present. Clinically, tumors of this type present no characteristics of malignancy. In a small percentage of cases, probably less than 10 per cent, these adenomas may be multiple. A few cases of adenoma in aberrant pancreatic tissue have been reported. Definitely malignant tumors of the islet cells occur in a small percentage of cases and may give rise to metastasis. These tumors are multiple somewhat more often than the benign adenomas. A condition described as adenomatosis of the islet cells has been reported in a few cases in association with hypoglycemia. In addition, a few cases of hypoglycemia have been reported with no apparent abnormality of the islet cells; however, cases of this type must be viewed with a certain degree of suspicion because of the possibility of an extremely small (smallest reported adenomas known to be associated with hypoglycemia 2.5 mm. in diameter) adenoma that was overlooked in pathologic examination of the pancreas. Medical treatment has never offered a satisfactory solution for the management of a patient who has a hyperfunctioning adenoma of the islets of Langerhans. In the exceptional borderline case of hypoglycemia, medical measures may control the symptoms fairly well; however, in this type of case, probably no true tumor of the islet cells is present. Some patients with a tumor of this type will give a history dating back four or five years or even longer. Usually, however the_history extends over a period of months or perhaps a year or two. Frequently, the pa-
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tient has discovered that glucose in some form will relieve his symptoms and has eaten excessively in order to prevent his symptoms. As a result, many of the patients are quite obese when they present themselves for operation, which of course adds to the difficulty of the surgical procedure. The surgical treatment of tumor of the islet cells associated with hypoglycemia may be very satisfactory if a relatively small functioning adenoma is found in an easily accessible portion of the gland. On the other hand, it may be much less satisfactory if no tumor is found or if an extensive neoplastic process is encountered. In the majority of cases, however, an adenoma is found and removed, along with a variable amount of the pancreas, and the patient enjoys a very satisfactory postoperative result. The abdominal incision which has been most satisfactory for exploration of the pancreas, in my experience, is a slightly curved transverse incision, with the convexity directed upward and placed approximately midway between the tip of the xiphoid and the umbilicus. The pancreas is then approached usually through the gastrocolic omentum by retracting the stomach anteriorly and upward. Some small adenomas of the islet cells have virtually the same consistency and color as normal pancreatic tissue, which may make their recognition difficult. This is especially true if the lesion is situated within the parenchyma of the gland so that it is not visible on the surface. Fortunately, most adenomas have a somewhat greater consistency than normal pancreatic tissue and also a deeper color, varying from a dark yellow to a brownish color. It is a good plan to explore carefully the entire pancreas as an initial procedure, since, even though a tumor is apparent, one must remember that multiple lesions may be expected in perhaps 10 per cent of cases in which the tumor is benign and somewhat oftener in cases in which a malignant lesion is present. Lateral mobilization of the duodenum aids in adequate inspection and palpation of the head of the pancreas. Only about 20 to 25 per cent of adenomas are found in the head of the gland, the remainder being in the body or tail, which, of course, is fortunate so far as removal of these lesions is concerned. If one finds a relatively small encapsulated tumor which can be removed by local excision, this is the simplest procedure and ordinarily can be accomplished in a satisfactory manner. At times, it may be necessary to resect a portion of the pancreas in order to remove the tumor. If this is done, resection of the pancreas should be started at the tail and carried toward the head of the gland until one has progressed far enough to include the tumor in the resected portion of pancreas. The remaining end of the pancreas is then sutured with catgut or silk. Resection of the pancreas so that a portion of the gland is left distally, disconnected from the rest of the pancreas, is inadvisable. The type of case which offers the most difficult problem is the one in which careful exploration of the entire pancreas reveals no tumor. This, of course, does not mean that there is no tumor present but merely that the surgeon is unable to locate a tumor. It has been my practice in 2
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recent years to resect approximately two thirds to three quarters of the pancreas in cases of this type, starting the resection distally at the tail and bringing it toward the head of the gland, usually a short distance to the right of the superior mesenteric vessels. In our experience at the Clinic, a good result may be anticipated if there is a tumor in the resected portion of the pancreas. In 1 case observed at the Clinic, the tumor was so small and so difficult to discover that it was not detected until several months after the operation, when the gland was carefully reexamined because the patient was apparently well. If no tumor is found in the resected portion of the pancreas, a favorable result is not expected, although exceptions to this rule have been reported. Usually, however, it is necessary to resect more pancreatic tissue at a subsequent operation. In the experimental animal it is necessary to resect at least 90 per cent of the pancreas in order to produce diabetes, and clinical evidence suggests a similar situation in man. A second resection is most likely to be successful in relieving the patient if a tumor is found in the resected portion. A search for ectopic pancreatic tissue is always advisable when no tumor is found in the pancreas. Although total pancreatectomy has been performed as a primary procedure in a case of hyperinsulinism in which no tumor could be found, this is not a recommended procedure. A check on the value of the fasting blood sugar at a suitable interval after operation affords evidence relative to the success of the operation.