[CANCER RESEARCH 37, 2387-2394, July 1977] Effects on Nutrition of Surgery of the Liver, Pancreas, and Genitourinary Tract1 Maurice E. Shils MemorialSloan-KetteringCancerCenter,Cornell universityMedicalCollege,New York,New York 10021 Summary Carcinoma of the pancreas is increasing in the United States and has a grave prognosis. Surgical treatment has moved from subtotal pancreatectomy to total pancreatec tomy and now to en bloc resection and vascular replace ment. Pancreatic exocrine and endocrine insufficiency fol lowing resection add to the nutritional problems presented by this major surgery and its high complication rate. Recog nition of these problems and adequate treatment decrease morbidity and mortality. Major hepatic resection imposes metabolic problems in the immediate postoperative period that are minimized by improving preoperative nutritional status and by providing adequate postoperative support with albumin and carbohydrate. Urinary tract diversion for pelvic cancer involving the ureters and/or bladder has pro gressed from ureterosigmoidostomy with its high incidence of disturbances of electrolyte and acid-base balance to ure teroileostomy with its appreciably lower rate of complica tions. alfold that when the tumor is in the head of the pancreas [Ref. 47; K. W. Warren, in published discussion following presentation by J. C. Fish (20)], with the rates in the other 2 categories being intermediate. In addition, the 5-year survival following surgery when carcinoma is in the head of the pancreas ranges from 13 to 18% [Ref. 47; K. W. Warren, in published discussion following presentation by J. C. Fish (20)] and that with tumor in the ampulla and duodenum is 2 (47) to 3 (65) times greater. Weight loss is a very common feature in carcinoma of the pancreas no matter where the lesion is located (10). It is often associated with jaundice and pain. Warren et al. (65) recorded preoperative weight losses, averaging 12 to 16 pounds@,depending on the site, in 253 patients with periam pullary cancer. Weight loss in patients with ductal carci noma of the pancreas commonly occurred in 39%, anorexia and asthenia in 15 and 14%, respectively, and steatorrhea in 9% (5). Resectability in the latter group is only 19%, and 5year survival after total pancreatectomy is very low (5, 56). Pancreatoduodenectomy Carcinomaof the Pancreas This operative procedure was described by Whipple et a!. (66) in 1935 for the surgical treatment of carcinoma of the Carcinoma of the pancreas is increasing and now ranks ampulla of Vater. During the early years of its application, 4th as the most common cause of death by cancer in males, operative mortality was extremely high (10) but has appreci exceeded only by lung, large bowel, and prostate cancer. ably decreased with experience and improved support tech The American Cancer Society estimated that in 1976 cancer niques and antibiotics. Other carcinomas of the periampul of the pancreas would cause 20,000 deaths in the United lary region that are amenable to treatment by this operation States with an estimated 23,000 new cases that would be include those of the distal common bile duct and duo diagnosed (1). denum. Some surgeons utilize it for carcinoma of the head of the pancreas. In the usual operative procedure the distal portion of the stomach is removed; the pancreas is tran Site of Carcinoma,Incidence,and Prognosis sected (usually at its neck but varying amounts may be removed or even the entire organ), and the duodenum and a The common bile duct lies behind the head of the pan few inches of jejunum distal to the ligament of Treitz are creas, which it grooves, and frequently joins the main pan resected. The entire specimen is removed by division of the creatic duct (duct of Wirsung) at the ampulla of Vater in the duodenum. Hence, this area has been termed “periampul common bile duct. A cholecystectomy is usually performed, lary.―The manifestations of carcinoma of the head of the and some surgeons perform a vagotomy. Various methods of reconstruction are possible. The extent of resection is pancreas and other malignant tumors of the periampullary indicated in Chart 1A; 1 type of reconstitution (retrocolic areas are so frequently undistinguishable that most writings on the subject consider these neoplasms together. The method) is shown in Chart lB. Three options are available to the surgeon in dealing with relative frequency of periampullary neoplasms in 4 series is the pancreatic stump: (a) inversion of the transected end of given in Table 1. There are 2 important aspects to this the pancreas into the jejunal lumen; (b) suturing the cut end distribution; the resectability rate by pancreatoduodenec of the duct of Wirsung to the jejunal mucosa; and (C) liga tomy for carcinoma of the ampulla of Vater is at least sever tion of the pancreatic duct with oversewing of the tran sected pancreas (Chart 2). There appear to be major differ bar 29 to December 1, 1976, Key Biscayne, Fla. ences of opinion among surgeons on the value of perform I Present at the Conference on Nutrition and Cancer Therapy, Novam JULY 1977 Downloaded from cancerres.aacrjournals.org on June 17, 2017. © 1977 American Association for Cancer Research. 2387 M. E. Shils Table 1 of Periampullary Frequency patientsRef. Cancers of Site% 35Ref. 37Ref. 47Ref. 65Pancreas83505038Ampulla10273237Duodenum471015Bileduct316810No. of patients15944239253 plications2 (10). Brunschwig (6) opposed anastomosis on the grounds that ligation of the pancreatic duct was simpler and that continued patency was highly unlikely with anasto mosis. In a retrospective comparison, Goldsmith et a!. (28) found no difference in postoperative morbidity and mortal ity or in histological appearance of the remnant at postmor tem examination in patients who had the pancreatic duct reimplanted at pancreatoduodenectomy and those who had the duct ligated and the cut end of the pancreas closed (Table 2). The decision as to the treatment of the pancreatic stump has nutritional implications, since ligation of the pancreatic duct with oversewing of the transected end of the pancreas will lead to complete pancreatic insufficiency in all instances. The postoperative complication rate in this procedure is high, reaching 50% or more in various published series. The result is prolonged hospitalization with a number of the problems interfering with normal food intake. Table 2 lists the incidence in 4 series of those complications which could be expected to affectnutritional status.Gastrointes tinal hemorrhage was often secondary to erosion caused by pancreatic fistulas. A B Chart 1. A, pancreatoduodenectomy. Lines of section of stomach, pan creas, duodenum, and common bile duct are shown; a vagotomy and chole cystectomy are indicated . B , anastomoses after resection and reconstruction using an antecolic loop of jejunum. The head of the pancreas has been removed, and its stump and duct have been closed [taken from Powis and Young (53)]. A B PancreaticInsufficiency The problem of exocrine enzyme insufficiency following pancreatoduodenectomy has been examined. Wollaeger et al. (69) studied 10 patients who had a number of variants in their surgical reanastomosis. In 8 patients with pancreatic duct reanastomosis observed 3 weeks to 1 year after sur gery, fat and nitrogen losses varied from normal to high. Fish et a!. (20) studied the absorption of 6 patients surviving 20 to 84 months postpancreatoduodenectomy in whom the pancreatic stump was invaginated into the end of the je junum. When no pancreatic extract was ingested, 3 patients had marked fat malabsorption (17 to 30%); this improved completely in 2 patients with pancreatic extract and partially in 1. Fecal nitrogen was increased in 3 patients and im Table 2 Postoperativecomplications of paricreatoduodenectomyfor malignantdisease%of patientsRef.Ref.Ref.Ref.Ref.Ref.Complications473156°56b28C28dHemorrhage823281599Pan fistula9142227Biliary Chart 2. Pancreatoduodenectomy. Diagrammatic representation of 4 methods used in the management of the pancreas. A, anastomosis of the pancreatic duct to the mucosa of the jejunum; B, inversion of the cut end of the pancreas into the jejunum; C, ligation of the pancreatic duct with over sewing of the transected end of the pancreas; D , total pancreatectomy [taken from Aston and Longmire (3)]. ing pancreatic duct anastomosis. The basis for the contro versy is related to the high incidence of postoperative pan creatic fistula, particularly in earlier experience, with its high morbidity and mortality (47, 59). Some have empha sized the importance of anastomosing the pancreatic duct to the intestinal tract to decrease this and associated com 2388 fistula784Peritonitis 519111318scessWound and/or ab infection914331149Ileus obstruction353773Intestinal or fistula0.4364No. patients2396836274534No. of with122362700total of patients pancreatec tomy a From 1942 to 1968. b From 1969 to 1972. C Pancreatic duct ligated. d Pancreatic duct anastomosed. CANCERRESEARCHVOL. 37 Downloaded from cancerres.aacrjournals.org on June 17, 2017. © 1977 American Association for Cancer Research. Surgery of Liver, Pancreas, and Genitourinary Tract proved with enzyme therapy. Two of 4 patients with periam pullary carcinoma had marked steatorrhea following pan creatoduodenectomy, with the pancreatic remnant anasto mosed to the stomach (12). Even for those undergoing resection for cancer of the ampulla, pancreatic exocrine insufficiency occurred in 27.7% (47). Following implanta tion of a portion of distal pancreas into the duodenum of dogs, the pancreatic remnant at sacrifice was found to be atrophied with dilation of the pancreatic duct and obstruc tion of the orifice in the duodenum (20). Others have also found atrophy and fibrosis of exocrine tissue after auto transplantation of the canine pancreas to the neck with an external fistula (16). Warren2 has emphasized that anasto mosis of the duct to jejunal mucosa had a much greater likelihood of maintaining a patent duct. Nevertheless, with this technique he has reported that 22% of his patients developed evidence of pancreatic exocrine insufficiency (65). Aston and Longmire (3) found that 7 of 28 patients had pancreatic insufficiency and 2 of these had had duct to mucosa anastomosis. The probability of pancreatic enzyme deficiency should be considered and checked in any patient with pancreato duodenectomy even with ductal reanastomosis. Pancreatic exocrine insufficiency leads to the loss of calories in the stool and to a deficiency of absorption of important nutri ents such as amino acids, calcium, magnesium, and fat soluble vitamins. Effective replacement necessitates the choice of an effective pancreatic extract and its use in adequate amounts. Although there are a number of prod ucts marketed for use as enzyme replacement therapy, there is relatively little quantitative information on their ac tual enzyme activities and comparisons of clinical effective ness. There have been a number of clinical reports of in creased fat absorption with commercial pancreatic extracts in patients following pancreatectomy (38, 53). Commercial extracts showed considerable differences in lipase activity when tested in vitro, with best results being obtained with Cotazym, Lipan, Panteric granules, and Viokase. It has been estimated that complete replacement of the pan creatic lipase secreted in 1 day by a normal man would require approximately 34 g of a high-potency preparation (27). Giulian et a!. (26) and Pairent et al. (53) have tested various commercial pancreatic supplements for their effec tiveness in improving fat absorption in dogs with the pan creatic duct ligated. Again, there was a considerable differ ence in effectiveness among such preparations with varia tions also depending on the method of measuring fat ab sorption. When fat absorption from regular test meals was measured, Progestive, Convertin, Viokase, Cotazym, and Panteric were among the better preparations. However, in the doses administered (6 tablets or capsules per day), none were capable of returning fat absorption to normal (53). We have found some patients to be intolerant of certain preparations and tolerant of others. In a few instances it has been necessary to use enteric coated preparations to avoid nausea and abdominal distress. The amounts of pancreatic extract recommended for treatment of such patients has varied from a minimum of 1.2 g2 up to 2.5 to 5.0 g (20, 38) per meal. Others have recom mended administration of 8 g divided into 12 hourly doses (36). Others have found no benefit of hourly dosage when the amounts given with meals were adequate (38). It has been suggested that, if a fully satisfactory result is not achieved with Viokase or Cotazym in doses of 2 to 3 g with each meal, the same daily dose should be given on an hourly basis. Where gastric secretion is normal, concomi tant administration of sodium bicarbonate may improve digestion. Since the surgical procedures for pancreatic car cinoma usually involve major gastric resection, bicarbonate administration does not appear indicated. Diabetes Another aspect of this procedure concerns the endocrine function of the remnant of pancreas. Decreased glucose tolerance has been noted in 10 pancreatoduodenectomized patients (5 to 39 months, post operative) in whom fasting blood sugar levels were within normal limits (12, 20). Miyata et a!. (45) have investigated this matter in more detail in pancreatoduodenectomized patients in whom at least the caudal half of the pancreas was preserved; the control group was composed of 12 gastrectomized patients with a Billroth II anastomosis. Fasting levels of glucose, nonesteri fied fatty acids, and immunoreactive insulin were within' normal limits; however, following glucose ingestion the blood sugar levels were appreciably higher than those of gastrectomized and normal individuals. The immunoreac tive insulin levels in the pancreatoduodenectomized pa tients were appreciably less than those of gastrectomized patients and only slightly higher than those of normal mdi viduals at 30 and 60 mm. Hence, insufficient insulin re sponse from the remnant of the pancreas appears to be a major cause of glucose intolerance in these cancer pa tients. This problem is complicated by the fact that approxi mately 10 to 12% of patients presenting with carcinoma of the pancreas are overtly diabetic (5, 28, 31) and 10 to 35% (depending on the site of the tumor) have asymptomatic glycosuria or hyperglycemia (65). The effect of pancreatic duct ligation in dogs on endo crine function was studied for approximately 7 months. One of the 16 dogs became continuously diabetic, although the others maintained normal blood sugars; but 9 had latent diabetes with intermittent hyperglycemic levels and abnor mal glucose tolerance curves (34). Four of 5 dogs with ligation with subsequent acinar tissue atrophy were found by Pairent et a!. (53) to have diabetic glucose tolerance curves. Others have found the ligated pancreas in dogs to retain adequate endocrine function for prolonged periods (40). Canine pancreas autotransplanted to the neck and with free flow of secretion became atrophic and fibrotic (16). The question has been raised as to the role of preexisting pancreatic pathology in the remnant of pancreas in contrib uting to pancreatic insufficiency (exocrine and endocrine) following pancreatoduodenectomy in patients with carci noma or pancreatitis. This has been studied in patients in whom such surgery had been performed following acute trauma and in whom residual pancreas was normal. Eight een to 24 months after the pancreatic remnant was sutured to the intestine, there was only mild elevation of fecal fat above normal, and jejunal lipase concentration following a JULY 1977 Downloaded from cancerres.aacrjournals.org on June 17, 2017. © 1977 American Association for Cancer Research. 2389 M. E. Shils test meal was normal; there was no clinical diabetes or need for insulin (57). In the 1 patient tested, serum insulin with and without glucose load was within normal limits. It was suggested that pancreatic insufficiency in patients with car cinoma or pancreatitis following partial resection is related to pathology in the remnant. Total Pancreatectomy and Regional Pancreatectomy stomach, duodenum, spleen, gallbladder, and common bile duct with skeletonizing of portal vein and hepatic artery. In type 2 there is the additional resection of the celiac axis and hepatic and/or superior mesenteric arteries. In individual patients gastrectomy may be total or subtotal, and varying amounts of colon and jejunum are removed as indicated (23, 24). Of 18 patients undergoing 1 of the procedures, 16 had been explored and deemed unresectable elsewhere. There were 3 postoperative deaths; 6 patients were alive at 1 year (24). The low 5-year survival rate of patients with carcinoma of the head of the pancreas (approximately 15%) has resulted in increasing advocacy of total pancreatectomy. This has been recommended because it eliminates the danger of pancreatic fistula without significantly increasing the surgi cal risk and because it eliminates the possibility of failure to remove carcinoma existing more distally either because of spread or multifocal tumor (5, 9, 15, 56). Total pancreatectomy poses a difficult metabolic situa tion with its resultant exocrine and endocrine insufficiency. Even with the optimum use of pancreatic extract, there tends to be increased loss of fat and nitrogen in stool. The usual diabetic-type diet with its increased protein and fat tends to exacerbate malabsorption and diarrhea. Replacing dietary fat with glucose to decrease steatorrhea increases the requirement for insulin. In a series of 48 totally pancrea tectomized patients followed with respect to their control of diabetes, Pliam et a!. (54) found that 50% were easily man aged, 8% were managed with difficulty only when there was concomitant illness, 18% had occasional hypoglycemic re actions managed with carbohydrate p.o. , 4% did poorly with persistent glycosuria, and 20% were found to be very difficult with ketoacidosis or hyperglycemic episodes re quiring hospitalization. Following pancreatectomy in dogs, plasma glucagon i@ present and may increase when insulin is not given (42). Following total pancreatectomy in a man, plasma (pan creatic) glucagon disappeared within 30 mm after resection but was present again after 18 hr and disappeared after 9 days. After an initial decrease, plasma glucagon-like immu noreactive substance(s) (measured by an antiserum that cross-reacts with glucagon-like products from small bowel mucosa) rose abruptly on the 2nd postoperative day and remained elevated thereafter (46). Because pancreatic tumors often extend beyond the pan creas at the time of exploration, resectability rate is low and survival is much lower despite total pancreatectomy. This is emphasized in the recent review of 101 cases of ductal carcinoma of the pancreas by Brooks and Culebras (5) who reported that 21 .8% were deemed inoperable because of metastases or poor condition of the patient, 24.8% had only a biopsy of the tumor at laparotomy, and 34.6% had some sort of palliative bypass, leaving only 18.8% who had sur gery performed with intention of cure. Survival of the latter group was poor. More radical surgery termed regional pan createctomy has been developed by Fortner (21) in an effort to remove en bloc the pancreas, adjacent tissue, and nodes along the primary lymph drainage. In the type 1 procedure there is total removal of the pancreas, pancreatic segment of portal vein, transverse mesocolon with middle colic yes sels, surrounding soft tissues, regional lymph nodes, distal 2390 In this complex and radical surgery a number of postoper ative complications with nutritional significance have oc curred. There were 6 patients with either gastrojejunal or colonic fistulas; 8 patients had significant infections, and many had prolonged postoperative recovery. Adequate nu tritional support has played a major role in permitting recov ery of many of these individuals. Because of infection, fistulas, anorexia, diarrhea, and malabsorption, usually in combination, prolonged total parenteral nutrition was used in maintaining a number of these patients and proved to be lifesaving. Because Intralipid has not been readily available, we have relied upon high-glucose infusions as the major source of calories, with insulin added to the total parenteral nutrition solutions initially at 1 unit of regular insulin for every 100 carbohydrate calories. Fractional coverage with regular insulin is given for glycosuria. The i.v insulin is then adjusted upward or downward as indicated. A xylose tolerance test has been performed preopera tively and postoperatively in a number of patients, in some cases with serial follow-up. Almost all of these patients have had depressed xylose absorption postoperatively; absorp tion returned to normal after a period of 4 to 9 months. Weight loss associated with depressed appetite and malab sorption has been significant; surviving patients are ap proximately 30% below their preoperative weight. Watery diarrhea has been frequent and has been associated with magnesium depletion and acidosis in some patients. The reason for this diarrhea and malabsorption of xylose is not clear but may be related variably to a number of factors including gastrectomy and duodenectomy, denervation and severance of lymphatics, small bowel resection in some instances, and bacterial overgrowth of small bowel. Five of 6 bowel fistulas closed spontaneously with total parenteral nutrition. Home total parenteral nutrition (58) permitted sur vival in 1 patient during a prolonged critical period of mal absorption. With cessation of parenteral support, anorexia, diabetes mellitus, pancreatic insufficiency, and other types of malabsorption continue to present serious nutritional problems to the radically pancreatectomized patient. There must be administration of adequate amounts of pancreatic extracts with all meals and snacks. Good control of the diabetes maximizes carbohydrate utilization and minimizes fluid and sodium losses secondary to osmotic diuresis caused by glycosuria. Medium-chain triglycerides are neu tral fats the fatty acids of which are primarily of the C8 and C,0type; these are more efficiently absorbed in the absence of pancreatic enzymes than are the usual long-chain fats. They are also absorbed more efficiently when there is an insufficiency of conjugated bile salts or when there are impaired absorptive mechanisms (32). Glucose oligosac charides may also be helpful in increasing the caloric intake CANCER RESEARCH VOL. 37 Downloaded from cancerres.aacrjournals.org on June 17, 2017. © 1977 American Association for Cancer Research. Surgery of Liver, Pancreas, and Genitourinary Tract and absorption in pancreatically insufficient patients, since these relatively short-chain glucose polymers can be hydro lyzed to glucose by the brush-border enzyme Sucrase-a dextrinase (30). This white powdery material is not sweet and may be used in a variety of ways to supplement intake. There may be reduction in vitamin B,2 absorption in ap proximately 40 to 50% of patients with chronic pancreatic insufficiency (64). Malabsorption of this vitamin has been observed in patients with total pancreatectomy (48). In these subjects the B12absorption is improved by administra tion of pancreatic extract. Liver Resection Until the early 1950's removal of liver tissue was usually limited to wedge or guillotine type of resection with rela tively minor losses in terms of function. With a description of a controlled technique for resection of the right lobe of the liver (39), major hepatic resection became frequent. It is not surprising that some of the earliest efforts thereafter involved resection of cancer (49-52). Advances in anesthe sia and operative techniques, blood replacement, antibiot ics, and understanding of metabolic derangements caused by massive liver resection have appreciably decreased mor bidity and mortality. The surgeon is now greatly aided by preoperative information for more precise localization of the tumor provided by computerized transaxial tomography and selective hepatic arteriography. Arteriography also pro vides valuable information on the pattern of hepatic artery branches to aid in their dissection. Recurrence of cancer after transplantation has been high. Starzl (62) recommended that patients with primary hepa toma should not be treated by transplantation. Williams et a!. (68) reported 1 patient of 6 with primary hepatomas living 3 years; 2 patients who had transplantation for metastatic disease and 4 of 5 patients having transplantation for carci noma of the hepatic duct were found to have tumor at autopsy. PreoperativeNutritionalCare Many patients with primary or secondary liver involve ment are undernourished; there may also be a history of alcoholism and the oombination may result in extensive fatty infiltration. This state imposes increased surgical risk in terms of normal metabolic response to surgical stress and increases mortality. McDermott and Ackroyd (43) have stressed the importance of delaying surgery if possible until some degree of nutritional repletion can be accomplished in malnourished patients. The mode of nutritional rehabili tation may involve p.o. , tube, or parenteral feedings, with the route and the nutrient composition depending upon the clinical situation. PostoperativeCare Normal liver tissue is endowed with a tremendous capac ity for regeneration. Nevertheless, after major hepatic re section the early biochemical and metabolic changes that Major resectionfor cancers has been performed forthe can occur can be serious and life-threatening. Appropriate most part in 5 situations: primary malignant liver tumors in steps are necessary to manage these changes to permit recovery and rapid regeneration . McDermott et al. (44) have adults; primary malignant liver tumors in infants and chil dren; cancer metastatic to liver from other sites; to permit reported a significant drop in blood sugar following resec en bloc excision of cancer of adjacent organs in stomach tions of 70% or more, and severe hypoglycemia has been noted in patients following total hepatectomy and liver and colon; and to palliate the malignant carcinoid syn drome. Up to 90% of the liver may be resected with survival transplantation. Other groups have not observed such of the patient. Total hepatectomy and orthotopic liver trans marked blood sugar changes following resection, perhaps plantation is possible in those patients who have extensive because of routine use of glucose postoperatively (2, 52). In primary cancer of the liver, gallbladder, and bile ducts or any case, it seems wise to obviate this danger by monitoring metastatic colon cancer confined to the liver. In addition, blood sugar and infusing 10% glucose solution i.v. continu resections are done for nonmalignant tumors such as be ously for at least the 1st several days or until adequate p.o. nign hepatomas, cholangiomas, hamartomas, angiomas, intake of carbohydrates is assured. Often following p.o. teratomas,and cysts. carbohydrate, blood sugar may be elevated for several The natural history of primary malignant liver tumors in weeks. Since the liver is the site of albumin synthesis, it is adults is such that almost all die with 3 to 7 months follow not surprising that hypoalbuminemia will occur to a sign ifi ing onset of symptoms. It is rare that a patient survives more cant degree unless replaced by parenteral administration. than 1 year. Foster's review (25) indicates that following Failure to do so can lead to progressive fall in osmotic resection there is a survival rate of 36% in non-Asian adults pressure in the vascular compartment and accumulation of with hepatoma; this excludes operative death in 22%. Pre marked interstitial fluid with increased vascular load and sumably, this survival rate should increase with more effec the danger of pulmonary edema. The need for supplemen tive chemotherapy. Hepatoma in infants and children is less tary albumin persists for approximately 1 week. The likely to metastasize early than is the adult variety (25). amounts of albumin given have usually averaged 25 g/day Operative death rate in this age group is 23% with a survival for the 1st 5 days or so (22, 44, 52). By the end of the 3rd of other patients for more than 5 years of 33.3%; a sign ifi postoperative week, nearly normal albumin levels are usu cant number of other patients were alive and free of disease ally found. at less than 5 years. Resection of metastases remains a Preoperatively, some patients [20% in the series of Pack controversial subject, but the data reviewed by Foster give and Molander (52)] may have elevated serum prothrombin encouragement for removal of localized and solitary meta time, which is corrected by preoperative administration of staticdisease of the liver. vitamin K, oxide i.m. Fibrinogen, prothrombin, and other JULY 1977 Downloaded from cancerres.aacrjournals.org on June 17, 2017. © 1977 American Association for Cancer Research. 2391 M. E. Shils coagulation factors (V, VII, IX, X) that are synthesized by the liver will fall following major resection (22, 44, 52). Despite the postoperative administration of vitamin K, prothrombin levels remained depressed in the postoperative phase; such depression is not reflected in any clinical disorder. These factors gradually return to normal as hepatic regeneration HepaticRegeneration Massive hepatic resection in man brings into focus the question of rate of regeneration and the factors affecting that rate. The remarkable ability of the liver in experimental animals to replace lost tissues rapidly and completely by progresses. compensatory cellular hypertrophy and hyperplasia has After subtotal hepatectomy there is a rapid fall in serum long been recognized and also occurs in man. The morpho triglycerides. This is expected since the liver is the major logical and biochemical sequence of events during regener source of serum triglycerides and since peripheral tissues ation in laboratory animals (primarily the rat) have been are continuously removing circulating fat. As serum triglyc reviewed together with consideration of regulatory mecha erides fall there is a rapid rise in levels of nonesterified fatty nisms (7, 33). Almost immediately after extirpation of ap acids,thatreflects an increasedmobilizationof fattyacids proximately two-thirds of the liver, a series of morphologi from adipose tissue (44). As hepatic regeneration proceeds cal changes appear; by as early as 6 hr postoperatively, there is progressive rise of the triglycerides and a fall in there is increased capacity to synthesize protein. These nonesterified fatty acids over the 1st several weeks. De changes culminate in an outburst of mitotic division in creased total serum calcium reflects a fall in serum albumin. parenchymal cells at 24 to 30 hr. The rat liver returns Transient low serum sodium and potassium have been re roughly on an exponential course to approximately normal ported in some patients after liver resection (2), while others size in 10 to 20 days. In his review Harkness (33) has pointed have reported low levels of serum inorganic phosphates out that considerable variations in diet have little effect on following clinical hepatic resection and hepatic transplanta the initial process of regeneration that may take place even tion (22, 23). Hypophosphatemia in dogs following partial on a protein-free dietinthe rat.The increasein number of hepatectomy is associated with increased hepatic uptake parenchymal cell nuclei is practically the same in starved as and diminished urinary excretion of phosphate (22). in fed animals, although the increase in weight of the liver is Evidence of liver decompensation has been observed in markedly less. cases of extended right hepatic lobectomy (52). In such Observations in man are relatively limited. Packetal. (50, instances reduction of protein intake and initiation of a 51) had opportunitiesfor direct visualizationof liver of medical regimen for hepatic precoma are indicated. These patients after major hepatic resection. In 1 patient there was disturbances disappear in a short period. At this time it is an estimated 50% increase in liver size in 1 week following important to provide sufficient intake of protein and other resection; another patient had complete regeneration in 5 nutrients to permit optimum liver regeneration. When he months. McDermott et a!. (44) have followed liver regenera patic dysfunction persists following resection or liver trans tion by ‘31-Iabeled rose bengal following major hepatic re plantation, and especially when this is associated with por section, and their data also indicate that there is restoration tal vein shunting, the i.v. amino acid regimen developed by of normal liver mass within 6 months. Fischer et a!. (19) may be useful. The rationale for this The question of the specificity and nature of “regenera therapy has been reviewed by Soeters and Fischer (60). tive stimulus― or the hepatotrophic substance or sub They postulate that, in catabolic states such as liver failure stances has been of continuing interest and appears to be and associated conditions such as sepsis, catecholamine gaining momentum. One stimulus to this subject has been discharge is associated with marked increases in glucagon the observation that Eck-fistula dogs develop not only he secretion and a decreased insulin:glucagon ratio. The re patic encephalopathy but also liver atrophy. Recent interest suit is a release of large amounts of amino acids from has centered on the probability that such a factor or factors protein sources; the aromatic amino acids cannot be catab derive from pancreas or other viscera and enter the liver via olized by the failing liver and accumulate in the circulation. the portal blood and on the role of pancreatic hormones. Decreased plasma branch-chain amino acids together with Rats made alloxan diabetic had a marked proliferative re the increased aromatic amino acids allow toxic aromatic sponse of their livers to insulin administration, although amino acids to penetrate the blood-brain barrier in in there was some regeneration after hepatic resection even if insulin treatment was withheld, suggesting that more than creased amounts and encephalopathy develops. The nutri ent formulation is designed to reverse the catabolic state by insulin was involved (70). Bucher and Swaffield (8) reported providing sufficient calories and other nutrients and to re that insulin and glucagon together stimulated hepatic re verse encephalopathy by increasing branch-chain amino generation in rats. Further support for the concept that acid concentration while decreasing aromatic amino acid glucagon and insulin are needed to produce maximal re concentration in order to restore the normal plasma molar sponse to partial hepatectomy in rats has been advanced ratio of branch-chain amino acids to aromatic amino acids (67). Starzl et a!. (63) found that infusion of insulin, but not and to reverse the amino acid losses from muscle and liver. of glucagon or of insulin and glucagon mixtures infused The administration of the keto analogs of 5 essential amino into the left portal vein of dogs following portal cava shunt, acids (valine, leucine, isoleucine, methionine, and phenyl reduced atrophy, preserved hepatocyte structure, and tre bled cell renewal. Since the insulin protection in this study alanine) and 5 amino acids (histidine, threonine, trypto phan, lysine, and arginine) i.v. or p.o. has been reported to was not quite complete, there may be missing ancillary improve portal-systemic encephalopathy in 8 of 11 patients substances. Contradictory data have been advanced in sug gesting that insulin is not a critical factor in regeneration in (41). 2392 CANCER RESEARCH VOL. 37 Downloaded from cancerres.aacrjournals.org on June 17, 2017. © 1977 American Association for Cancer Research. Surgery of Liver, Pancreas, and Genitourinary Tract rabbits (11) or dogs (17). Regardless ofthe origin or nature of the hepatotrophic factor(s), it would appear that optimal regeneration rates of the liver require adequate nutritional support during the hypertrophic stage. Urinary Diversion for Pelvic Cancer Urinary diversion is required for pelvic malignant tumors that necessitate cystectomy. The simplest methods of un nary diversion are nephrostomy, which involves simply in serting a tube through the skin into the pelvis of the kidney, or a cutaneous ureterostomy,inwhich 1 or both uretensare brought to the skin. Serious problems of infection and patient comfort led Coffey in 1911 (14) to publish a descnip tion of an implantation of ureters into the sigmoid colon (ureterosigmoidostomy). A high incidence of obstruction of the ureters following implantation with resultant hydrone phrosis led to a variety of modifications for ureteral implan tation. In addition, there was frequent pyelonephnitis caused by ascending infection from continual fecal contam ination. Metabolic problems also occurred. In a large series Ferris and Odel (18) found that 79% of their patients had some degree of hyperchloremia and 80% were acidotic at varying intervals following ureterosigmoidostomy. A clinical syndrome was associated with the acidosis consisting of thirst, anorexia, vomiting, fatigue, and malaise, and in chil dren a failure to grow and vitamin-resistant rickets were noted. In addition to the hyperchloremic acidosis, hypo phosphatemia and hypokalemia developed. Prior to discov ery of the relation of this syndrome to potassium homeosta sis, the accepted treatment for this syndrome was a low-salt diet with added sodium bicarbonate (18). A number of urol ogists felt initially that the primary problem related to the development of pyelonephnitis with renal dysfunction. How ever, it became increasingly apparent that the metabolic basis for the syndrome was the result of absorption in the colon of significant amounts of sodium and chloride from the urine with resultant osmotic diuresis and potassium loss (61). Local secretion of potassium by the colon was another source of ionic loss. Metabolic acidosis markedly increases aldosterone secretion, and this plays a role in potassium wastage. Potassium depletion intensifies acidosis because of decreased urinary bicarbonate reabsorption. Because of the inherent metabolic problems of ureterosigmoidostomy, this procedure has essentially been abandoned. However, there are still patients who had this procedure done some years ago who continue to have the metabolic problems. Ureterosigmoidostomy was replaced by a cutaneous ure teroileostomy (ileal conduit) (4). In this surgical procedure a segment of ileum approximately 20 cm long is resected with its blood supply; the continuity of the ileum is restored, the uretens are sutured to the ileal mucosa, the proximal end of the segment is closed, and the distal end is brought to the abdominal opening. When the resection has healed, the urine is collected in the bag. There is some reabsorption of urea and other urine constituents by the ileum. However, the relatively short segment of ileum with runoff into the bag minimizes metabolic problems as compared to the ureterosigmoidostomy. In addition, this procedure has the advantage of separating the urine contents from intestinal contents with resultant decreased retrograde kidney infec tion. It has been found that in approximately 2 years the villi of the mucosa of the segment are lost (29). Approximately 10 years ago there was a short-lived inter est in using a jejunal segment instead of an ileal segment for bladder formation. However, clinical experience soon dem onstrated that metabolic problems occurred with this ap proach. These changes were the opposite of those occur ring with ureterosigmoidostomy. Hyponatremia, hypochlo remia, and hyperkalemia occurred because of loss of so dium and chloride in excess of water into the jejunal blad den and reabsorption of potassium; azotemia developed secondarily to hypovolemia and impaired glomerular filtra tion (13). 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F. Hepatic Proliferative Re sponse to Insulin in Severe Alloxan Diabetes. Cancer Res., 26: 14081414, 1966. CANCER RESEARCHVOL. 37 Downloaded from cancerres.aacrjournals.org on June 17, 2017. © 1977 American Association for Cancer Research. Effects on Nutrition of Surgery of the Liver, Pancreas, and Genitourinary Tract Maurice E. Shils Cancer Res 1977;37:2387-2394. Updated version E-mail alerts Reprints and Subscriptions Permissions Access the most recent version of this article at: http://cancerres.aacrjournals.org/content/37/7_Part_2/2387 Sign up to receive free email-alerts related to this article or journal. To order reprints of this article or to subscribe to the journal, contact the AACR Publications Department at [email protected]. To request permission to re-use all or part of this article, contact the AACR Publications Department at [email protected]. Downloaded from cancerres.aacrjournals.org on June 17, 2017. © 1977 American Association for Cancer Research.
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