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Surgical prevention and treatment of late normal tissue injury
Surgical Prevention and Treatment of Late Normal Tissue Injury H. SchraffordtKoops and H.J. Hoekstra There is a definite increase in combined-modality treatment of malignancies. Surgery, radiation therapy, and/or chemotherapy often are combined. A disadvantage is the increased risk for short- and long-term complica. tions, especially radiation-induced damage to normal healthy tissue such as intestine and bone. Brachytherapy and intraoperative radiotherapy are new radiation techniques with the potential to increase the radiation dose to the tumor while reducing the radiation dose to surrounding normal tissues. The surgical transposi-
tion of organs outside the pathway of the ionizing beam is a new surgical technique often used in the pelvis. Radiation damage to the gastrointestinal tract is often mentioned. Fibrosis and obstruction may occur as a result of stricture formation or fibrinous adhesions. Ischemic necrosis of the bowel wall may lead either to perforation or fistulae. Mucosal damage and lymphatic obstruction can cause malabsorption. These complications are difficult to manage and should be treated in specialized centers.
ne year after Wilhelm Conrad R6ntgen published his description o f ' A new kind of ray" in 1895, the first complications were described, Within a few years, the immediate and delayed pathological effects of radiation on most normal and malignant tissues were well known. First, dermatitis was widely recognized as a common problem following exposure to x-rays) It is now well known that some normal cells expressed an early (acute) radiation reaction, eg, hematopoietic tissues, skin epidermis, mucosa of the gastrointestinal (GI) tract, and testicular epithelium; whereas other tissues show late (chronic) reactions, eg, liver, kidney, lung, bone and soft tissue, vascular endothelium, mesothelium, glial tissue, cardiac tissue, and the endocrine glands2 For many years, research projects have been carried out to protect healthy normal tissue around a tumor against radiotherapy. Current examples of the resulting techniques are brachytherapy, intraoperative radiotherapy (]ORT), and operative transposition of tissue and organs outside a radiation field. In this article, techniques of surgical prevention for radiotherapy are described, and also the treatment of late normal tissue injury is discussed. Because most late complications of radiotherapy are seen in the GI tract, this subject is described.
age at an incidence of 5% to 25%, especially when doses exceed 40 to 50 Gy. Small bowel minimal and maximal tolerance doses approximate 45 to 50 and 55 to 65 Gy, respectively. 3 It is known that some parts of the small bowel are anatomically more predisposed to radiation damage then others: the duodenum because of its fixation in the retroperitoneal position, and the proximal jejunum and terminal ileum, whose morbidity is limited by the short mesentery. Small bowel loops immobilized by adhesions formed after previous surgery are more prone to radiation damage and, therefore, the maximum tolerance dose is around 45 Gy. Large bowel tolerates radiation better than small bowel. Roswit et al 4,5 described men with testicular cancer irradiated on retroperitoneal lymph nodes. At doses between 40 and 54 Gy; 9% to 11% of patients developed constriction or obstruction of the colon, but it rose to 17% at 55 to 59 Gy and to 37% at 60 to 64 Gy. Minimal tolerance for radiation involving a portion of the rectum in patients with prostate cancers to be 65 to 70 Gy has been well-established. Green et al 6 found rectal injury rates of 1% after 64 to 68 Gy and 5% after 70 to 73 Gy with external irradiation for prostate cancer.
O
Damage to the GI Tract After Radiotherapy Pelvic malignancies frequently require postoperative radiation therapy that may induce small bowel damFrom the Department of Su~'gicat Or~cology, Groningen University Hospital, Groningen,the Netherlands. Address reprint requeslsto H. SchraffbrdtKoops,MD, PhD, Department of Surgical Oncolog),,Groningen UniversityHospital, Oostersinge159,9713 EZ, Groningen,The Netherlands. Cop),~ght 9 1994 by 14d.B.Saunders Cornpony 1053-4296/94/0402-0008505.00/0
Copyright 9 1994by W.B. Saunders Company
Brachytherapy, IORT, and Other Surgical Prevention Brachytherapy is a type of treatment in which radioactive sources are placed immediately adjacent to or within a tumor. High dose is thus administered to the immediate area with a rapid fall off in intensity as distance from the source increases. Brachytherapy has the unique advantage of delivering a high dose of irradiation within a short time to a limited tumor volume without excessive exposure to the surround-
Seminars in Radiation Oncology, Vol 4, No 2 (Ap~l), 1994.'pp 119-122
1 19
120
SchraJ~brdtKoopsand Hoekstra
ing normal structure. In a number of cases, brachytherapy is applied after an operation, eg, after an (incomplete) resection of a soft tissue tumor located in an arm or leg. To reduce the radiation dosage to operator, theatre, and nursing staff "after loading" systems have been developed. IORT delivered during a surgical procedure provides the opportunity for displacing out of the treatment volume or for shielding radiosensitive normal tissues or viscera, such as stomach or intestine. IORT may have theoretical advantages over conventional fractionated external beam radiotherapy by limiting exposure of normal tissue to radiation and, therefore, limiting radiation toxicity, particularly to the GI tract. 7 There are logistic difficulties in the use of this treatment. Either a high energy facility must be available in the operating theatre, which of course would require the very extensive shielding requirements of an}, linear accelerator, or the patient must be moved to a suite in the radiotherapy department specially prepared to manage a patient undergoing open surgery. Initial data from a few centers, particularly in the United States, Japan, and Western Europe, suggest an important adjuvant role for the treatment of advanced rectal, pancreatic, and gastric tumors. 7 Doses of 15 to 20 Gy IORT are well tolerated by any tissue. IORT is generally used as a boost therapy in combination with fractionated external beam radiotherapy without an extreme treatment-related morbidity. ~,9 In 1975, Green et aP ~ suggested an operative transposition of organs by a mechanical method of reducing the exposure of the small intestine during pelvic radiation. He proposed the creation of a pelvic diaphragm with peritoneal flaps, thus excluding small intestine from the pelvis. Others include the use of a sling of synthetic polyglycolic acid (PGA) mesh inserted to form a higher pelvic floor as a permanent barrier keeping the small bowel from the pelvis. LH3 In the 1991 study of Rodier et al, ~l 60 patients from three French cancer institutes underwent surgical treatment that included the insertion of a PGA mesh intestinal sling. After completion of the primary surgical procedure, a single thickness of PGA mesh (21.5 x 26.5 cm) was sutured to the posterior peritoneum wall at the level of sacral promontory. Care was taken to avoid trauma of great vessels and ureters. The PGA mesh then was sutured with an interrupted suture (2-0 Vicryl) inferior to the coecum, around the rectosigmoid, and along each lateral gutter. After interposition of omentum between the synthetic mesh and the loops,
the mesh was pulled and finally attached to the anterior abdominal wall in the midepigastric region above the umbilicus. The total PGA mesh placement took approximately 30 minutes. Barium studies after completion of radiotherapy showed continued elevation of bowel 2 months after surgery. Magnetic resonance imaging was used to check the PGA mesh position and its complete resorption at the third to fifth postoperative month. Much more easily, a silicone gel-filled implant (breast prosthesis) or a silicone rubber, expandable balloon can be used to exclude small bowel from the peMs. 14,15 We have used the breast prosthesis implant several times in our surgical department in Groningen with good results; a disadvantage of this method is removal of the prosthesis after radiation. Lechner and Cesnik 16described the technique of omentopexy. They form a bag from the greater omentum, which houses the intestinal loops. The lower margin of the omentum is attached to the parietal peritoneum of the posterior abdominal wall beyond the promentorium. The lateral edges are sutured to the ascending and descending colon. Because patients with abdominal, pelvic, or retroperitoneal malignancies are often treated with radiation therapy, the surgical oncologist has to reduce the postoperative morbidity as much as possible. The surgical technique and skill especially will reduce the risk for bowel adhesions and, therefore, reduce the risk for radiation-induced enteritis. On the other hand, an uncomplicated recovery of the patient will prevent an undelayed adjuvant irradiation and improve the therapeutic effect.
T r e a t m e n t of Radiotherapy-Induced Late Normal Tissue Injury in t h e Abdomen The symptoms and signs clearly depend on the site and nature of the underlying pathology. Mucosal and lymphatic abnormalities can give rise to malabsorbtion of varying degrees) 7 Fibrosis and obstruction may occur as a result of stricture formation or fibrinous adhesions. Ischemic necrosis of the bowel wall may lead either to perforation or fistula formation. In some patients, chronic radiation enteritis becomes clinically obvious after a disease-free interval of 6 to 12 months, and sometimes after many years. In exceptional cases, the symptoms of acute enteritis never entirely disappear and a chronic enteritis emerges. Small-bowel obstruction is often the clinical presentation of this enteritisJ s
Preventionand TreatmentofRadiation Damage
Radiation-induced injuries of the small intestine and colon provide the gastroenterologist and surgeon with a great therapeutic challenge. Numerous reviews have attended to the progressive and potentially lethal nature of these injuriesJ 9 Galland and Spencer 2~ stated in their excellent book, Radiation L~teritis, "There are two main problems which face a surgeon when operating on a patient with radiation enteritis. First, irradiated gut heals poorly, and secondly, bowel which appears normal may be damaged microscopically." On the top of this, irradiated guts usually are firmly fixed and fragile. For this reason, it is generally accepted that surgery where possible should be avoided. A conservative approach should be adopted as long as possible. Therefore, treatment can be divided into (1) correction of metabolic abnormalities; (2) treatment of inflammation; and (3) surgery only in exceptional cases. Sometimes surgery cannot be avoided because of small bowel obstruction and strictures not reacting on conservative treatment. In patients presenting with a perforation, emergency surgery is mandatory. Enterocutaneous fistulae virtually always require surgical intervention. Similarly, fistula involving the colon and rectum will not close on conservative management. The main problem for the surgeon in these cases is: if resection is necessary, how wide should resection of the irradiated bowel be? Ideally, the two ends of bowel used for anastomosis should be free of disease, but as said before, the appearance of irradiated gut is not reliable. The following general principles for treatment of patients with radiation-damaged gut can be given. Symptoms of a recurrence of the original malignancy after radiotherapy are sometimes the same as the symptoms of radiation-damage. Biochemical abnormalities and malnutrition should be corrected first. Wide resection of irradiated bowel lesions is the best method of treatment, but the first problem is mobilizing the usually firmly fixed bowels. Second, it is difficult to recognize exactly which part of the gut is irradiated and which is not, especially when a large part of the lower abdomen is radiated. Galland and Spencer ~l described their experience in the Hammersmith Hospital in London in 1986: the majority of the radiation-induced lesions were in the distal ileum, sigmoid, or rectum. The coecum, ascending colon, transverse colon, and descending colon were seldom involved. Their results were the best with the following treatment philosophy: terminal ileum resection and hemicolectomy on the right side followed by an ileo-transverse anastomosis or rectosigmoid resec-
12 1
tion followed by mobilization of the splenic flexure to bring it down for anastomosis, thus ensuring that healthy bowel was used for at least one side of the anastomosis. Others advocate bypassing (without resection) the diseased segment whenever possible. In 1984, we published an article stating that marginally sufficient circulation is probably the cause of the high leak rate and mortality rate after resection of irradiated bowel.la A side-to-side anastomosis does not interfere with the mesenteric vessels and a longitudinal incision on the antimesenteric side of the small bowel may preserve a larger blood supply. Swan et al ~2 reviewed the literature and, in a collected series of 199 patients, the mortality rate after resection was 21% compared with 10% after bypass. In their own series of 45 patients, the mortality for resection and bypass was 53% and 7%, respectively. However, patients and mortality rates in resection and bypass groups are not comparable in the literature series. When resection has been carried out for perforation, patients usually are in a poor nutritional state, have a contaminated peritoneal cavity, and are more severely ill then those with chronic small bowel obstruction. On the other hand, patients in whom the diseased bowel was bypassed may have had a mass of small bowel loops fixed together in the lower abdomen to the extent that the resection was technically impossible and at least unwarranted. To improve disease-free and overall survival, cancer patients are more and more treated by combined modality therapies consisting of surgery, radiation therapy, and/or chemotherapy. A disadvantage is the increased risk for short- and long-term complications, especially radiation-induced complications of previous normal healthy tissue such as intestine and bone. The treatment of complications in cancer patients is complex and difficult and can best be fulfilled in specialized cancer centers because radiation bowel injuries are a great therapeutic challenge for gastroenterologists and surgical-oncologists. It also has to be remembered that radiation enteritis in most of the cases is a life-long disorder, often requiring frequent hospital admissions.
References 1. RowlandS: Report on the action of the new photographyto medicine and surgery.Br MedJ 1:197-198, 1896 2. Awwad HK: Radiation effects on normal tissues: General principles, in Radiation Oncology:Radiobiologicaland Physiological Perspectives. Dordrecht, The Netherlands, Kluwer, 1990,pp 109-127
122
SchrajTbrdtKoopsand Hoekstra
3. Rubin P: The Franz Busche Lecture: Late effects of chemotherapy and radiation therapy: A new hypothesis. IntJ Radiat Oncol Biol Phys 10:5-34, 1984 4. Roswit B, Malsky SJ, Reid CB: Severe radiation injuries of the stomach, small intestine, colon and rectum. AmJ Roentgenol Radium Ther Nucl Med 114:460-475, 1972 5. Roswit B: Complications of radiation therapy: The alimentary' tract. Semin Roentgenol 9:51-63, 1974 6. Green N, Goldberg H, Goldman H, et al: Severe rectal injury following radiation for prostatic cancer. J Urol 131:701-704, 1984 7. Hoekstra HJ, Sindelar WR, Kinsella TJ, et al: History; prelimina~, results, complications and future prospects of int raoperative radiotherapy.J Surg Onco136:175-182, 1987 8. Cromack DT, Maher MM, Hoekstra HJ, et al: Are complications in intraoperative radiation therapy more frequent than in conventional treamwnt? Arch Surg 124:229-234, 1989 9. Sindelar WF, Kinsella TJ, Chen PW, el al: Intraoperative radiotherapy in retroperitoneal sarcomas. Final results of a prospective, randomized, clinical trial. Arch Surg 128:402410, 1993 10. Green N, Iha G, Smith WR: Measures to minimize small intestine injury in the irradiated pelvis. Cancer 35:1633-1640, 1975 I 1. RodierJ-F,JanserJ-C, Rodier D, et al: Prevention of radiation enteritis by an absorbable polyglycolic acid mesh sling. A 60-case multicentrie study. Cancer 68:2545-2549, 1991 12. Devereux DF, Chandler JJ, Eisenstat T, et al: Efficac3" of an absorbable mesh in keeping the small bowel out of the human pelvic following surgery. Dis Col Rect 31:17-21, 1988
13. Soper JT, Clarke-Pearson DL, Creasman WT: Absorbable synthetic mesh (910-polyglactin) intestinal sling to reduce radiation-induced small bowel injury" in patients with peMc malignancies. Gynecol Onco129:283-289, 1988 14. Ball AB, Cassoni A, Watkins RM, et al: Silicone implant to prevent visceral damage during adjuvant radiotherapy for retroperitoneal sarcoma. BrJ Radio163:346-348, 1990 15. Sezeur A, Abbou C, Chopin D, et al: Protection of the small intestine against irradiation by means of a removable prosthesis. Asaio Transaction 36:M681-683, 1990 16. Lechner P, Cesnik H: Abdominopelvic omentopexy: Preparatory, procedure for radiotherapy" in rectal cancer. Dis Colon Rectum 35:1157-1160, 1992 17. Sassoon L, Hodgson HJ: The medical management of radiation enteritis, in Galland l/B, Spencer J (eds): Radiation Enteritis. Arnold, 1990, 7:176-198 [8. Wobbes Th, Verschueren RCJ, Lubbers EJC, et al: Surgical aspects of radiation enteritis of the small bowel. Dis Col Rect 27:89-92, 1984 19. DeCosseJJ, Rhodes RS, Wentz WB, et al: The natural history' and management of radiation induced injury of the gastrointestinal tract. Ann Surg 170:369-384, 1969 20. Galland liB, SpencerJ: General principles of surgical management, in Galland RB, Spencer J (eds): Radiation Enteritis. City, State, Arnold, 1990, 7:206-2t3 21. Galland RB, Spencer J: Surgical management of radiation enteritis. Surgery' 99:133-139, 1986 22. Swan RW, Fowler WC, Boronnw RC: Surgical management of radiation injury' to the small intestine. Surg Gynecol Obstet 142:325-327, 1976
tion of organs outside the pathway of the ionizing beam is a new surgical technique often used in the pelvis. Radiation damage to the gastrointestinal tract is often mentioned. Fibrosis and obstruction may occur as a result of stricture formation or fibrinous adhesions. Ischemic necrosis of the bowel wall may lead either to perforation or fistulae. Mucosal damage and lymphatic obstruction can cause malabsorption. These complications are difficult to manage and should be treated in specialized centers.
ne year after Wilhelm Conrad R6ntgen published his description o f ' A new kind of ray" in 1895, the first complications were described, Within a few years, the immediate and delayed pathological effects of radiation on most normal and malignant tissues were well known. First, dermatitis was widely recognized as a common problem following exposure to x-rays) It is now well known that some normal cells expressed an early (acute) radiation reaction, eg, hematopoietic tissues, skin epidermis, mucosa of the gastrointestinal (GI) tract, and testicular epithelium; whereas other tissues show late (chronic) reactions, eg, liver, kidney, lung, bone and soft tissue, vascular endothelium, mesothelium, glial tissue, cardiac tissue, and the endocrine glands2 For many years, research projects have been carried out to protect healthy normal tissue around a tumor against radiotherapy. Current examples of the resulting techniques are brachytherapy, intraoperative radiotherapy (]ORT), and operative transposition of tissue and organs outside a radiation field. In this article, techniques of surgical prevention for radiotherapy are described, and also the treatment of late normal tissue injury is discussed. Because most late complications of radiotherapy are seen in the GI tract, this subject is described.
age at an incidence of 5% to 25%, especially when doses exceed 40 to 50 Gy. Small bowel minimal and maximal tolerance doses approximate 45 to 50 and 55 to 65 Gy, respectively. 3 It is known that some parts of the small bowel are anatomically more predisposed to radiation damage then others: the duodenum because of its fixation in the retroperitoneal position, and the proximal jejunum and terminal ileum, whose morbidity is limited by the short mesentery. Small bowel loops immobilized by adhesions formed after previous surgery are more prone to radiation damage and, therefore, the maximum tolerance dose is around 45 Gy. Large bowel tolerates radiation better than small bowel. Roswit et al 4,5 described men with testicular cancer irradiated on retroperitoneal lymph nodes. At doses between 40 and 54 Gy; 9% to 11% of patients developed constriction or obstruction of the colon, but it rose to 17% at 55 to 59 Gy and to 37% at 60 to 64 Gy. Minimal tolerance for radiation involving a portion of the rectum in patients with prostate cancers to be 65 to 70 Gy has been well-established. Green et al 6 found rectal injury rates of 1% after 64 to 68 Gy and 5% after 70 to 73 Gy with external irradiation for prostate cancer.
O
Damage to the GI Tract After Radiotherapy Pelvic malignancies frequently require postoperative radiation therapy that may induce small bowel damFrom the Department of Su~'gicat Or~cology, Groningen University Hospital, Groningen,the Netherlands. Address reprint requeslsto H. SchraffbrdtKoops,MD, PhD, Department of Surgical Oncolog),,Groningen UniversityHospital, Oostersinge159,9713 EZ, Groningen,The Netherlands. Cop),~ght 9 1994 by 14d.B.Saunders Cornpony 1053-4296/94/0402-0008505.00/0
Copyright 9 1994by W.B. Saunders Company
Brachytherapy, IORT, and Other Surgical Prevention Brachytherapy is a type of treatment in which radioactive sources are placed immediately adjacent to or within a tumor. High dose is thus administered to the immediate area with a rapid fall off in intensity as distance from the source increases. Brachytherapy has the unique advantage of delivering a high dose of irradiation within a short time to a limited tumor volume without excessive exposure to the surround-
Seminars in Radiation Oncology, Vol 4, No 2 (Ap~l), 1994.'pp 119-122
1 19
120
SchraJ~brdtKoopsand Hoekstra
ing normal structure. In a number of cases, brachytherapy is applied after an operation, eg, after an (incomplete) resection of a soft tissue tumor located in an arm or leg. To reduce the radiation dosage to operator, theatre, and nursing staff "after loading" systems have been developed. IORT delivered during a surgical procedure provides the opportunity for displacing out of the treatment volume or for shielding radiosensitive normal tissues or viscera, such as stomach or intestine. IORT may have theoretical advantages over conventional fractionated external beam radiotherapy by limiting exposure of normal tissue to radiation and, therefore, limiting radiation toxicity, particularly to the GI tract. 7 There are logistic difficulties in the use of this treatment. Either a high energy facility must be available in the operating theatre, which of course would require the very extensive shielding requirements of an}, linear accelerator, or the patient must be moved to a suite in the radiotherapy department specially prepared to manage a patient undergoing open surgery. Initial data from a few centers, particularly in the United States, Japan, and Western Europe, suggest an important adjuvant role for the treatment of advanced rectal, pancreatic, and gastric tumors. 7 Doses of 15 to 20 Gy IORT are well tolerated by any tissue. IORT is generally used as a boost therapy in combination with fractionated external beam radiotherapy without an extreme treatment-related morbidity. ~,9 In 1975, Green et aP ~ suggested an operative transposition of organs by a mechanical method of reducing the exposure of the small intestine during pelvic radiation. He proposed the creation of a pelvic diaphragm with peritoneal flaps, thus excluding small intestine from the pelvis. Others include the use of a sling of synthetic polyglycolic acid (PGA) mesh inserted to form a higher pelvic floor as a permanent barrier keeping the small bowel from the pelvis. LH3 In the 1991 study of Rodier et al, ~l 60 patients from three French cancer institutes underwent surgical treatment that included the insertion of a PGA mesh intestinal sling. After completion of the primary surgical procedure, a single thickness of PGA mesh (21.5 x 26.5 cm) was sutured to the posterior peritoneum wall at the level of sacral promontory. Care was taken to avoid trauma of great vessels and ureters. The PGA mesh then was sutured with an interrupted suture (2-0 Vicryl) inferior to the coecum, around the rectosigmoid, and along each lateral gutter. After interposition of omentum between the synthetic mesh and the loops,
the mesh was pulled and finally attached to the anterior abdominal wall in the midepigastric region above the umbilicus. The total PGA mesh placement took approximately 30 minutes. Barium studies after completion of radiotherapy showed continued elevation of bowel 2 months after surgery. Magnetic resonance imaging was used to check the PGA mesh position and its complete resorption at the third to fifth postoperative month. Much more easily, a silicone gel-filled implant (breast prosthesis) or a silicone rubber, expandable balloon can be used to exclude small bowel from the peMs. 14,15 We have used the breast prosthesis implant several times in our surgical department in Groningen with good results; a disadvantage of this method is removal of the prosthesis after radiation. Lechner and Cesnik 16described the technique of omentopexy. They form a bag from the greater omentum, which houses the intestinal loops. The lower margin of the omentum is attached to the parietal peritoneum of the posterior abdominal wall beyond the promentorium. The lateral edges are sutured to the ascending and descending colon. Because patients with abdominal, pelvic, or retroperitoneal malignancies are often treated with radiation therapy, the surgical oncologist has to reduce the postoperative morbidity as much as possible. The surgical technique and skill especially will reduce the risk for bowel adhesions and, therefore, reduce the risk for radiation-induced enteritis. On the other hand, an uncomplicated recovery of the patient will prevent an undelayed adjuvant irradiation and improve the therapeutic effect.
T r e a t m e n t of Radiotherapy-Induced Late Normal Tissue Injury in t h e Abdomen The symptoms and signs clearly depend on the site and nature of the underlying pathology. Mucosal and lymphatic abnormalities can give rise to malabsorbtion of varying degrees) 7 Fibrosis and obstruction may occur as a result of stricture formation or fibrinous adhesions. Ischemic necrosis of the bowel wall may lead either to perforation or fistula formation. In some patients, chronic radiation enteritis becomes clinically obvious after a disease-free interval of 6 to 12 months, and sometimes after many years. In exceptional cases, the symptoms of acute enteritis never entirely disappear and a chronic enteritis emerges. Small-bowel obstruction is often the clinical presentation of this enteritisJ s
Preventionand TreatmentofRadiation Damage
Radiation-induced injuries of the small intestine and colon provide the gastroenterologist and surgeon with a great therapeutic challenge. Numerous reviews have attended to the progressive and potentially lethal nature of these injuriesJ 9 Galland and Spencer 2~ stated in their excellent book, Radiation L~teritis, "There are two main problems which face a surgeon when operating on a patient with radiation enteritis. First, irradiated gut heals poorly, and secondly, bowel which appears normal may be damaged microscopically." On the top of this, irradiated guts usually are firmly fixed and fragile. For this reason, it is generally accepted that surgery where possible should be avoided. A conservative approach should be adopted as long as possible. Therefore, treatment can be divided into (1) correction of metabolic abnormalities; (2) treatment of inflammation; and (3) surgery only in exceptional cases. Sometimes surgery cannot be avoided because of small bowel obstruction and strictures not reacting on conservative treatment. In patients presenting with a perforation, emergency surgery is mandatory. Enterocutaneous fistulae virtually always require surgical intervention. Similarly, fistula involving the colon and rectum will not close on conservative management. The main problem for the surgeon in these cases is: if resection is necessary, how wide should resection of the irradiated bowel be? Ideally, the two ends of bowel used for anastomosis should be free of disease, but as said before, the appearance of irradiated gut is not reliable. The following general principles for treatment of patients with radiation-damaged gut can be given. Symptoms of a recurrence of the original malignancy after radiotherapy are sometimes the same as the symptoms of radiation-damage. Biochemical abnormalities and malnutrition should be corrected first. Wide resection of irradiated bowel lesions is the best method of treatment, but the first problem is mobilizing the usually firmly fixed bowels. Second, it is difficult to recognize exactly which part of the gut is irradiated and which is not, especially when a large part of the lower abdomen is radiated. Galland and Spencer ~l described their experience in the Hammersmith Hospital in London in 1986: the majority of the radiation-induced lesions were in the distal ileum, sigmoid, or rectum. The coecum, ascending colon, transverse colon, and descending colon were seldom involved. Their results were the best with the following treatment philosophy: terminal ileum resection and hemicolectomy on the right side followed by an ileo-transverse anastomosis or rectosigmoid resec-
12 1
tion followed by mobilization of the splenic flexure to bring it down for anastomosis, thus ensuring that healthy bowel was used for at least one side of the anastomosis. Others advocate bypassing (without resection) the diseased segment whenever possible. In 1984, we published an article stating that marginally sufficient circulation is probably the cause of the high leak rate and mortality rate after resection of irradiated bowel.la A side-to-side anastomosis does not interfere with the mesenteric vessels and a longitudinal incision on the antimesenteric side of the small bowel may preserve a larger blood supply. Swan et al ~2 reviewed the literature and, in a collected series of 199 patients, the mortality rate after resection was 21% compared with 10% after bypass. In their own series of 45 patients, the mortality for resection and bypass was 53% and 7%, respectively. However, patients and mortality rates in resection and bypass groups are not comparable in the literature series. When resection has been carried out for perforation, patients usually are in a poor nutritional state, have a contaminated peritoneal cavity, and are more severely ill then those with chronic small bowel obstruction. On the other hand, patients in whom the diseased bowel was bypassed may have had a mass of small bowel loops fixed together in the lower abdomen to the extent that the resection was technically impossible and at least unwarranted. To improve disease-free and overall survival, cancer patients are more and more treated by combined modality therapies consisting of surgery, radiation therapy, and/or chemotherapy. A disadvantage is the increased risk for short- and long-term complications, especially radiation-induced complications of previous normal healthy tissue such as intestine and bone. The treatment of complications in cancer patients is complex and difficult and can best be fulfilled in specialized cancer centers because radiation bowel injuries are a great therapeutic challenge for gastroenterologists and surgical-oncologists. It also has to be remembered that radiation enteritis in most of the cases is a life-long disorder, often requiring frequent hospital admissions.
References 1. RowlandS: Report on the action of the new photographyto medicine and surgery.Br MedJ 1:197-198, 1896 2. Awwad HK: Radiation effects on normal tissues: General principles, in Radiation Oncology:Radiobiologicaland Physiological Perspectives. Dordrecht, The Netherlands, Kluwer, 1990,pp 109-127
122
SchrajTbrdtKoopsand Hoekstra
3. Rubin P: The Franz Busche Lecture: Late effects of chemotherapy and radiation therapy: A new hypothesis. IntJ Radiat Oncol Biol Phys 10:5-34, 1984 4. Roswit B, Malsky SJ, Reid CB: Severe radiation injuries of the stomach, small intestine, colon and rectum. AmJ Roentgenol Radium Ther Nucl Med 114:460-475, 1972 5. Roswit B: Complications of radiation therapy: The alimentary' tract. Semin Roentgenol 9:51-63, 1974 6. Green N, Goldberg H, Goldman H, et al: Severe rectal injury following radiation for prostatic cancer. J Urol 131:701-704, 1984 7. Hoekstra HJ, Sindelar WR, Kinsella TJ, et al: History; prelimina~, results, complications and future prospects of int raoperative radiotherapy.J Surg Onco136:175-182, 1987 8. Cromack DT, Maher MM, Hoekstra HJ, et al: Are complications in intraoperative radiation therapy more frequent than in conventional treamwnt? Arch Surg 124:229-234, 1989 9. Sindelar WF, Kinsella TJ, Chen PW, el al: Intraoperative radiotherapy in retroperitoneal sarcomas. Final results of a prospective, randomized, clinical trial. Arch Surg 128:402410, 1993 10. Green N, Iha G, Smith WR: Measures to minimize small intestine injury in the irradiated pelvis. Cancer 35:1633-1640, 1975 I 1. RodierJ-F,JanserJ-C, Rodier D, et al: Prevention of radiation enteritis by an absorbable polyglycolic acid mesh sling. A 60-case multicentrie study. Cancer 68:2545-2549, 1991 12. Devereux DF, Chandler JJ, Eisenstat T, et al: Efficac3" of an absorbable mesh in keeping the small bowel out of the human pelvic following surgery. Dis Col Rect 31:17-21, 1988
13. Soper JT, Clarke-Pearson DL, Creasman WT: Absorbable synthetic mesh (910-polyglactin) intestinal sling to reduce radiation-induced small bowel injury" in patients with peMc malignancies. Gynecol Onco129:283-289, 1988 14. Ball AB, Cassoni A, Watkins RM, et al: Silicone implant to prevent visceral damage during adjuvant radiotherapy for retroperitoneal sarcoma. BrJ Radio163:346-348, 1990 15. Sezeur A, Abbou C, Chopin D, et al: Protection of the small intestine against irradiation by means of a removable prosthesis. Asaio Transaction 36:M681-683, 1990 16. Lechner P, Cesnik H: Abdominopelvic omentopexy: Preparatory, procedure for radiotherapy" in rectal cancer. Dis Colon Rectum 35:1157-1160, 1992 17. Sassoon L, Hodgson HJ: The medical management of radiation enteritis, in Galland l/B, Spencer J (eds): Radiation Enteritis. Arnold, 1990, 7:176-198 [8. Wobbes Th, Verschueren RCJ, Lubbers EJC, et al: Surgical aspects of radiation enteritis of the small bowel. Dis Col Rect 27:89-92, 1984 19. DeCosseJJ, Rhodes RS, Wentz WB, et al: The natural history' and management of radiation induced injury of the gastrointestinal tract. Ann Surg 170:369-384, 1969 20. Galland liB, SpencerJ: General principles of surgical management, in Galland RB, Spencer J (eds): Radiation Enteritis. City, State, Arnold, 1990, 7:206-2t3 21. Galland RB, Spencer J: Surgical management of radiation enteritis. Surgery' 99:133-139, 1986 22. Swan RW, Fowler WC, Boronnw RC: Surgical management of radiation injury' to the small intestine. Surg Gynecol Obstet 142:325-327, 1976