Solid and Papillary Neoplasms of the Pancreas

Solid and Papillary Neoplasms of the Pancreas

PANCREATIC NEOPLASMS 0039--6109/95 $0.00 + .20 SOLID AND PAPILLARY NEOPLASMS OF THE PANCREAS Michael J. Zinner, MD Solid and papillary neoplasms ...

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PANCREATIC NEOPLASMS

0039--6109/95 $0.00

+ .20

SOLID AND PAPILLARY NEOPLASMS OF THE PANCREAS Michael

J. Zinner, MD

Solid and papillary neoplasms are rare malignant neoplasms of the pancreas that, until recently, had been identified as several other types of tumors. This group of tumors, also known as papillary and cystic or solid and papillary epithelial neoplasms of the pancreas, have been incorrectly diagnosed in the past as adenocarcinomas, islet cell tumors, cystadenomas, or cystadenocarcinomas. This is a unique tumor, and none of these other tumor types are appropriate designations because they all have different functional, epidemiologic, morphologic, and prognostic consequences. CLINICAL CHARACTERISTICS AND DIAGNOSIS

Solid and papillary neoplasms of the pancreas are very rare tumors that occur predominantly in young women. They are almost always diagnosed because of their large size and present with an asymptomatic abdominal mass. Most reports indicate that these large palpable, abdominal masses occur in females in their second and third decades of life. The mean age of most presenting young women is between 22 and 27 years, with age ranges from 13 to 73 years. 2• 14 Rarely, an older male is reported, but the demographics call into question the appropriate diagnosis in these unusual cases. Occasionally, the presenting symptoms have been the acute onset of abdominal pain with positive peritoneal signs due to rupture of the tumor.6 Specifically missing from the symptom complex are symptoms referable to functional islet cell tumors of

From the Department of Surgery, Brigham and Women's Hospital; and the Department of Surgery, Harvard Medical School, Boston, Massachusetts

SURGICAL CLINICS OF NORTH AMERICA VOLUME 75 • NUMBER 5 • OCTOBER 1995

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the pancreas, weight loss, or the anorexia usually associated with highergrade malignancies. Obstructive jaundice is not usually present because of the slow-growing nature of the tumor. The diagnosis is often implied by radiologic examination (Fig. 1). Choi et aF reported on six cases examined by computed tomography (CT). All cases showed well-encapsulated, round, or lobulated masses consisting of both cystic and solid areas. Cystic portions showed CT numbers that suggested hemorrhagic necrosis, and no internal septations were seen within the masses (Fig. 2). In three tumors located in the head of the pancreas, dilatation of the biliary tree was absent or minimal, although the masses were very large. Two tumors contained calcification. One tumor demonstrated metastatic deposits in the liver and in the lymph nodes, and these appeared radiologically similar to the primary pancreatic masses. These authors concluded that solid and papillary neoplasm of the pancreas should be considered the primary diagnosis when characteristic CT findings are detected in young female patients. Balthazar et all reported the results of angiography and sonography in the diagnosis of these lesions. On ultrasonography, they are sharply defined nonhomogeneous tumors, lacking in central enhancement. On angiography, they present as avascular or hypovascular lesions depending on the degree of central necrosis. Because of their slowgrowing nature, they tend to encase vessels and displace them (Fig. 3).

Figure 1. Upper GI series showing large retroperitoneal mass compressing midbody of stomach. (From Zinner MJ, Shurbaji MS, Cameron JL: Solid and papillary epithelial neoplasms of the pancreas. Surgery 108:475-480, 1990 [patient OW]; with permission.)

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Figure 2. CT scan showing large mass with central necrosis and no septations. (From Zinner MJ, Shurbaji MS, Cameron JL: Solid and papillary epithelial neoplasms of the pancreas. Surgery 108:475-480, 1990 [patient DW]; with permission.)

Figure 3. Aortogram showing large hypovascular mass displacing aorta and compressing the splenic artery. (From Zinner MJ, Shurbaji MS, Cameron JL: Solid and papillary epithelial neoplasms of the pancreas. Surgery 108: 475-480, 1990 [patient DW]; with permission.)

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In one of the few reports on magnetic resonance imaging, Ohtomo et apa reported six young women, mean age 26 (range 13 to 73). On T1weighted spin-echo images, tumors were well demarcated and areas of high signal intensity were evident within them. On gross examination, these areas corresponded to solid portions with marked hemorrhagic necrosis or they were solid portions filled with a cystic component of hemorrhagic debris resembling a cyst. In three of the four masses a rim of low-intensity image correlated with a surrounding fibrous capsule. Again, these authors concluded that when Tl-weighted spin-echo imaging reveals obvious areas of high intensity within a sharply marginated tumor of the pancreas, especially in young women, solid and papillary epithelial neoplasm should be the primary diagnostic consideration. Aspiration cytology can be used in the diagnosis of these lesions 13 but is rarely helpful in directing therapy because therapy is always excisional. PATHOLOGIC FINDINGS

The hallmark histologic pattern of this tumor is a solid and papillary epithelial pattern in a pancreatic neoplasmll, 14 (Fig, 4), The variants include small, uniform eosinophilic cells forming papillary microcystic and solid structures with extensive hemorrhage and necrosis. In some tumors with long-standing necrosis, formations of cholesterol granulomas can be seen? A controversy remains as to the cell of origin for this tumor. Schlosnagle and Campbell12 described two pancreatic solid and papillary neoplasms occurring in young women. Characteristics indicated a duct cell origin in one, and, although the other was ultrastructurally similar, it contained neurosecretory granules. Because considerable evidence indicates that cells of small pancreatic ducts give rise to islet cells, the second case suggests that some tumors of ductal origin recapitulate the embryogenesis of the pancreatic islets and therefore may contain neurosecretory granules without showing the classic morphology of the more common pancreatic endocrine tumors. However, other attempts to classify immunohistochemical markers have not been successful in this subclass of pancreatic tumors. Morohoshi et al 9 reported 16 solid and papillary neoplasms of the tumor and 22 other pancreatic lesions immunocytochemically investigated using antiserum against several pancreatic enzymes, hormones, and tumor markers. They used four pancreatic enzymes (alpha-amylase, lipase, trypsinogen, and chymotrypsinogen), four pancreatic hormones, neuron-specific enolase (NSE), alpharantitrypsin (AAT), carcinoembryonic antigen (CEA), and CA 199. The solid and papillary tumors of the pancreas did not react with pancreatic enzymes, neuroendocrine granules, or any pancreatic hormones, and only 2 of 16 stained positive for NSE. All tumors including the nonsolid and papillary neoplasm stained for AAT, indicating a lack of specificity. The conclusion of the authors was that there is as yet no marker specific for solid and papillary neoplasms which could elucidate

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Figure 4. Typical morphologic speCimen showing sheets of eosinophilic cells and papillary projections.

the obscure histogenetic origin and phenotypic differentiation of these tumors. One report in the literature describes a solid and papillary neoplasm arising from an ectopic pancreas at the base of the mesocolon. s This occurred in a 13-year-old girl with an 8-cm tumor that histologically showed solid sheets and papillary arrangements of small eosinophilic cells with AA T-positive cytoplasm. This is a single case report and the only one known in the literature but also suggests a nonendocrine origin. Recently, Matsunou et al 8 have reported a possible variant to solid and papillary neoplasms of the pancreas. It is a solid infiltrating variety. In their report of four cases, the tumors were histologically, histochemically, and ultrastructurally characteristic of the papillary cystic neoplasm but lacked the capsule commonly observed and possessed an infiltrating portion. Although Matsunou et alB describe these as a variant, infiltration has been seen in other series. Perhaps the difference is that these tumor cells did have infiltration among the pancreatic parenchyma in solid and pseudopapillary patterns, and pleomorphic atypism was observed in some parts of these tumors. They refer to these as solid, infiltrating papillary cystic neoplasms to differentiate them from ordinary encapsulated papillary cystic neoplasms. Although no signs of recurrence have been noted after surgical treatment in these patients, the infiltrating

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growth pattern and the presence of pleomorphic atypism suggest higher malignancy than the ordinary papillary cystic neoplasms. The other characteristic in this group of patients was that it tended to occur in older individuals. Of the four patients with this variant, two were men and two women; they were 39 and 51 years old, respectively.

TREATMENT Surgical excision is the primary form of treatment for solid and papillary neoplasms of the pancreas. A single case report by Fried et aP suggested that solid and papillary neoplasms of the pancreas are radiosensitive and can be successfully treated by radiation therapy. However, the most effective treatment is surgical excision. With a mean follow-up of 10 years (range 4 to 20), we 14 reported seven women, mean age 22 (range 16 to 33 years) with large tumors ranging from 7 to 20 cm, all alive and well. One of the patients had metastatic tumor to her liver which was unresectable, and all other patients underwent resection, including two distal pancreatectomies (Fig. 5), two total pancreatectomies, one pancreaticoduodenectomy (Whipple), and one local excision. Four of the seven patients had evidence of local invasion alone and one had liver metastases plus local invasion. In another series, six young females, mean age 26, had surgical excision by a radical pancreaticoduodenectomy,1 a 75% distal pancreatec-

Figure 5. Distal pancreatectomy and splenectomy for large tumor. (From Zinner MJ, Shurbaji MS, Cameron JL: Solid and papillary epithelial neoplasms of the pancreas. Surgery 108:475-480, 1990 [patient OW]; with permission.)

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tomy,2 a partial pancreatectomy and pancreaticogastrostomy/ total pancreatectomy/ and in one patient with an unresectable tumor a Roux-enY cyst jejunostomy. Follow-up in this series was 40 to 83 months, with four of the six patients alive and two having died of unrelated causes. Although we do not advocate cyst jejunostomy, others7 have reported long-term (greater than 2 years) survival in these patients. The one patient in our series14 with metastatic solid and papillary neoplasm to the liver had previously been misdiagnosed as having a pancreatic pseudocyst and had a cyst jejunostomy without resection. Because these lesions are surgically curable by excision, we strongly favor removal of all the tumor. SUMMARY

Solid and papillary neoplasms of the pancreas are rare, low-grade malignant tumors histologically distinct from usual ductal adenocarcinomas and islet cell tumors and amenable to cure by surgical excision. Because these lesions have been incorrectly diagnosed in the past as adenocarcinomas or cystadenocarcinomas, they may have contributed to reports with confusing survival statistics following resections for malignant neoplasms of the pancreas. In young women with large, relatively asymptomatic tumors of the pancreas, solid and papillary neoplasms should be high on the list of the differential diagnoses. References 1. Balthazar EJ, Subrmanyam BR, Lefleur RS, et al: Solid and papillary epithelial neoplasm of the pancreas: Radiographic, CT, sonographic, and angiographic features. Radiology 150:39-40, 1984 2. Choi BI, Kim KW, Han MC, et al: Solid and papillary epithelial neoplasms of the pancreas: CT findings. Radiology 166:413-416, 1988 3. Fried P, Cooper J, Balthazar E, et al: A role for radiotherapy in the treatment of solid and papillary neoplasms of the pancreas. Cancer 56:2783--2785, 1985 4. Friedman AC, Lichtenstein JE, Fishman EK, et al: Solid and papillary epithelial neoplasm of the pancreas. Radiology 154:333--337, 1985 5. Ishikawa 0, Ishiguro S, Ohhigashi H, et al: Solid and papillary neoplasm arising from an ectopic pancreas in the mesocolon. Am J Gastroenterol 85:597-601, 1990 6. Jeng LB, Chen MF, Tang RP: Solid and papillary neoplasm of the pancreas: Emphasis on surgical treatment. Arch Surg 128:433-436, 1993 7. Kuo TT, Su ij, Chien CH: Solid and papillary neoplasm of the pancreas: Report of three cases from Taiwan. Cancer 54:1469-1474, 1984 8. Matsunou H, Konishi F, Yamamichi N, et al: Solid, infiltrating variety of papillary cystic neoplasm of the pancreas. Cancer 65:2747-2757, 1990 9. Morohoshi T, Kanda M, Horie A, et al: Immunocytochemical markers of uncommon pancreatic tumors: Acinar cell arcinoma, pancreatoblastoma, and solid cystic (papillary-cystic) tumor. Cancer 59:739-747,1987 10. Ohtomo K, Furui S, Onoue M, et al: Solid and papillary epithelial neoplasm of the pancreas: MR imaging and pathologic correlation. Radiology 184:567-570, 1992 11. Sanfey H, Mendelsohn G, Cameron JL: Solid and papillary neoplasm of the pancreas: A potentially curable surgical lesion. Ann Surg 197:272-275, 1983

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12. Schlosnagle DC, Campbell WG Jr: The papillary and solid neoplasm of the pancreas: A report of two cases with electron microscopy, one containing neurosecretory granules. Cancer 47:2603-2610, 1981 13. Wilson MB, Adams DB, Garen PD, et al: Aspiration cytologic, ultrastructural, and DNA cytometric findings of solid and papillary tumor of the pancreas. Cancer 69:22352243, 1992 14. Zinner MJ, Shurbaji MS, Cameron JL: Solid and papillary epithelial neoplasms of the pancreas. Surgery 108:475-480, 1990 Address reprint requests to

Michael J. Zinner, MD Department of Surgery Brigham and Women's Hospital 75 Francis Street Boston, MA 02115