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Biomedical subjects

H A Pitt

Publications and source records attributed to H A Pitt.

At least 109 records · Page 6Linked to original sources

Current management of benign bile duct strictures.

Benign bile duct strictures remain one of the most difficult problems encountered by the hepatobiliary surgeon. The vast majority of bile duct strictures occur as a complication of cholecystectomy. The patients may present early in the postoperative period with evidence of a biliary leak or months to years later with the development of jaundice or cholangitis. The essential first step of management consists of delineation of the proximal biliary anatomy. Current management techniques include either operative biliary reconstruction or nonoperative balloon dilatation by either the percutaneous transhepatic or endoscopic routes. The best form of surgical reconstruction of the biliary tree is a biliary-enteric anastomosis from the proximal bile duct to a Roux-en-Y limb of jejunum. In these cases, we favor the use of long-term postoperative biliary stenting using Silastic stents. Recent retrospective, nonrandomized results from our institution favor this surgical technique over nonoperative dilatation. Primary sclerosing cholangitis is a rare cause of biliary strictures. The etiology of sclerosing is unknown, but its association with ulcerative colitis and other diseases suggest an autoimmune condition. The diagnosis is confirmed by typical cholangiographic findings of multiple areas of stricture and dilatation. No medical management has proven to be successful. Surgical management for symptomatic patients includes resection of the hepatic bifurcation with long-term transhepatic stenting of the biliary tree for patients with primarily extrahepatic and/or hilar disease and with no evidence of cirrhosis. In patients with primarily intrahepatic strictures or advanced cirrhosis, liver transplantation is the treatment of choice. Benign strictures due to other causes, such as chronic pancreatitis, calculous biliary disease, sphincter of Oddi stenosis, duodenal Crohn's disease, peptic ulcer, or perivaterian duodenal diverticula usually can be managed by choledochoduodenostomy or choledochojejunostomy without long-term stenting. The management of other rare benign biliary strictures is dependent upon their extent and underlying etiology.

Catheterization↗

Reoperative surgery for periampullary adenocarcinoma.

In recent years, the morbidity, mortality, and long-term survival of patients undergoing surgery for periampullary adenocarcinoma have improved. These changes have prompted us to reoperate on patients who have previously undergone pancreatobiliary surgery, many of whom were initially considered to have unresectable lesions. From 1979 to 1990, 38 patients with pancreatic and 17 patients with nonpancreatic periampullary adenocarcinoma underwent reexploratory surgery at The Johns Hopkins Hospital, Baltimore, Md. Thirty-three (60%) of these 55 patients had resection at the time of second laparotomy. Of the 46 patients undergoing reexploratory surgery with an intent to resect, the overall resection rate was 72% (33), 64% (16/25) for pancreatic and 100% for nonpancreatic periampullary adenocarcinoma. Postoperative complications occurred in 21 patients (38%), but only one patient (2%) died following surgery. Mean survivals from reexploratory surgery were 6.9 months for the 22 patients with pancreatic cancer undergoing palliative surgery, 20.5 months for the 16 patients with resectable pancreatic cancer, and 33.0 months for the 17 patients with nonpancreatic periampullary adenocarcinoma undergoing resection. We conclude that in carefully selected patients, reoperative surgery for periampullary cancer (1) provides a significant resection rate, (2) can be performed safely, and (3) offers a chance for long-term survival.

Adenocarcinoma↗

Why does somatostatin cause gallstones?

Long-term administration of the somatostatin analogue, octreotide, is complicated by gallstone formation. Somatostatin is known to inhibit hepatic bile secretion and gallbladder emptying. However, the effect of octreotide on gallbladder bile composition remains unknown. Therefore, we tested the hypothesis that octretide would alter hepatic bile composition and cause gallbladder stasis, thereby increasing gallbladder bile solute concentrations. Fourteen control prairie dogs received daily saline injections, whereas 10 animals received 1 micrograms of octreotide subcutaneously three times per day for 5 days. Cholecystectomy and common bile duct cannulation were then performed. Octreotide increased hepatic bile concentrations of bilirubin monoglucuronide (p less than 0.05), total bilirubin (p less than 0.05), and total protein (p less than 0.01). Rsa, an index of gallbladder stasis, was decreased (p less than 0.01) in the octreotide group. Gallbladder bile total calcium (p less than 0.05), bilirubin monoglucuronide (p less than 0.05), total bilirubin (p less than 0.01), total protein (p less than 0.05), and total lipids (p less than 0.05) were increased in the octreotide group. Animals receiving octreotide also had decreased hepatic (p less than 0.05) and gallbladder (p less than 0.001) bile pH. No differences in cholesterol saturation index were observed. These data suggest that in the prairie dog, octreotide (1) alters hepatic bile composition, (2) causes gallbladder stasis, and (3) increases gallbladder bile calcium, bilirubin, protein, lipid, and hydrogen ion concentrations. We conclude that octreotide causes alterations in gallbladder bile composition that increase the likelihood of cholesterol and calcium bilirubinate precipitation.

Animals↗

Cost-effectiveness of extracorporeal shock-wave lithotripsy versus cholecystectomy for symptomatic gallstones.

To evaluate the cost-effectiveness of extracorporeal shock-wave lithotripsy vs. cholecystectomy for symptomatic gallstones, a model was constructed that projects charges and survival for both treatments. For a 45-year-old woman with one small stone, treatment with extracorporeal shock-wave lithotripsy rather than cholecystectomy is projected to result in an average gain of only 3 days of life and an average increase in direct medical charges of $1729 over 5 years of follow-up. The resulting marginal cost-effectiveness of extracorporeal shock-wave lithotripsy vs. cholecystectomy is $216,000 of extra charges per year of life gained with extracorporeal shock-wave lithotripsy. Extracorporeal shock-wave lithotripsy is projected to be much more cost-effective for elderly than for young patients (10-20-fold difference), but considerably less cost-effective for multiple stones than a single stone (2-4-fold difference), and less cost-effective for women than men (twofold difference). Adjusting for effects of morbidity on quality of life, extracorporeal shock-wave lithotripsy is projected to have slightly better quality-adjusted survival than cholecystectomy for the small subset of patients with one stone (by 8 to 43 days at 5 years) but not for young patients with multiple stones. It is concluded that decisions about appropriate use of extracorporeal shock-wave lithotripsy should consider the effects of patient characteristics on clinical and economic outcomes.

Aged↗

Bilirubin monoglucuronide promotes cholesterol gallstone formation.

Recent evidence suggests that cholesterol (Ch) solubility in bile is determined by a complex interaction of mixed micelles and lecithin-cholesterol vesicles. Bilirubin monoglucuronide (BMG), which binds to bile salts and incorporates into mixed micelles, may displace cholesterol from micelles into vesicles, thus favoring cholesterol monohydrate crystal precipitation. Therefore, we designed an experiment to test the hypothesis that BMG may enhance cholesterol gallstone formation without inducing cholesterol supersaturation. For 8 weeks, 28 adult male prairie dogs were fed either a control, nonlithogenic diet (0.03% Ch), a high carbohydrate diet (CHO) which has no cholesterol but increases hepatic bilirubin secretion, or the same CHO diet plus 0.03% Ch. Cholecystectomy was then performed, and bile was examined microscopically for stones or crystals and analyzed for BMG and biliary lipids. Cholesterol saturation index was calculated. Cholesterol gallstones were found in none of the control animals and in 13% of the CHO-fed animals. However, the addition of trace cholesterol to the CHO diet resulted in an 88% incidence of cholesterol gallstones (P less than 0.001 vs control, P less than 0.01 vs CHO, respectively). Gallbladder bile was unsaturated with cholesterol in all groups. (control = 0.65 +/- 0.05, CHO = 0.46 +/- 0.05, CHO + 0.03% Ch = 0.70 +/- 0.03). CHO feeding alone or with trace cholesterol significantly elevated gallbladder bilirubin monoglucuronide, phospholipid, and cholesterol concentrations when compared to controls. These data suggest that in the prairie dog a high carbohydrate diet with only trace amounts of cholesterol increases bilirubin monoglucuronide in gallbladder bile and causes cholesterol gallstone formation without inducing cholesterol supersaturation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Short-term fasting increases biliary calcium and bilirubin.

Fasting has been associated clinically with the development of gallbladder sludge and pigment gallstones, both of which are composed primarily of calcium bilirubinate. Although fasting has been demonstrated to increase the cholesterol saturation of bile, its effect on biliary calcium and bilirubin has not been investigated. We, therefore, tested the hypothesis that short-term fasting would increase gallbladder bile calcium and bilirubin levels. Fifteen prairie dogs were studied. Seven animals were not fasted, whereas eight were fasted for 16 hr prior to acute experiments. Gallbladder and hepatic bile samples were obtained and analyzed for calcium, bilirubin, pH, and biliary lipids. Gallbladder bile ionized calcium levels were significantly increased in fasted animals (1.7 +/- 0.2 mM) compared to those in nonfasted animals (1.1 +/- 0.1 mM). Similarly, total calcium (4.3 +/- 0.5 mM vs 2.3 +/- 0.3 mM), total bilirubin (63 +/- 12 microM vs 29 +/- 8 microM), and bilirubin monoglucuronide (58 +/- 10 microM vs 22 +/- 8 microM) were significantly increased in the fasted group. Fasted animals were also noted to have an increased biliary cholesterol saturation index (0.57 +/- 0.04 vs 0.36 +/- 0.03) and decreased biliary pH (6.9 +/- 0.1 vs 7.6 +/- 0.1). These data indicate that in the prairie dog short-term fasting results in significant alterations in gallbladder bile composition. The increased concentrations of gallbladder calcium and bilirubin observed in these experiments may account, in part, for the formation of pigment gallstones and gallbladder sludge seen clinically with prolonged fasting.

Animals↗

Predictive factors for bactibilia in acute cholecystitis.

Acute cholecystitis is well established as one of the high-risk factors bactibilla and wound infection. However, many patients with acute cholecystitis do not have bactibillia. Therefore, we analyzed 20 clinical and laboratory parameters in 49 patients with acute cholecystitis to determine which factor(s) predicted bactibilla. Twenty-one (42.9%) of 49 patients with pathologically proved acute cholecystitis had positive bile and/or gallbladder wall cultures. Univariate analysis suggested that a preoperative temperature greater than 37.3 degrees C, a total serum bilirubin level greater than 8.6 mumol/L, and a white blood cell count greater than 14.1 x 10(9)/L were the best predictors of bactibilia. Multifactorial analysis demonstrated that the 17 patients with zero or one predictive factor had a significantly lower chance of having bactibilia than the 32 patients with two or three predictive factors (6% vs 63%). We concluded that the culture status of patients with acute cholecystitis can be predicted preoperatively. We propose that patients with acute cholecystitis and zero or one of the predictive factors receive a single preoperative antibiotic dose. In patients with two or three predictive factors, antibiotics should be continued until culture data are available.

Acute Disease↗

A history of the bilioenteric anastomosis.

The bilioenteric anastomosis has played an integral role in the surgical management of biliary tract disease during the past century. A wide variety of techniques for suturing a portion of the biliary tract to the digestive tract have been described since von Winiwarter's first cholecystoenterostomy. Many types of biliary stents have also been developed, although their exact role remains controversial. Many advances in preoperative and postoperative care have contributed to the low morbidity and mortality of current reconstructive biliary tract surgery.

Anastomosis, Surgical↗

Pylorus preserving pancreatoduodenectomy: an overview.

Pylorus preserving pancreatoduodenectomy (PPPD) was reintroduced 12 years ago. Since that time, over 400 patients have undergone PPPD with approximately 41 per cent having chronic pancreatitis and 54 per cent having pancreatic and other periampullary malignancies. Reported 5-year survivals in this latter group have been comparable to those achieved by the classic Whipple procedure. The postoperative mortality rate in 339 reported patients has been 3.8 per cent. Postoperative morbidity, including delayed gastric emptying, has been similar to that of the classic Whipple operation. However, PPPD has been associated with fewer late problems with dumping, diarrhoea, delayed gastric emptying (8.6 per cent), and marginal ulceration (3.6 per cent). Moreover, most patients undergoing PPPD have been able to return to their preoperative and preillness weight. The additional advantage of decreased operative time makes PPPD an attractive alternative to the classic pancreatoduodenectomy.

Duodenum↗

The effect of calcium on gallbladder absorption.

The absorption of water and electrolytes is an important physiologic function of the gallbladder which is altered during gallstone formation. Extracellular calcium and calcium channel antagonists are known to affect intestinal absorption, yet their effect on gallbladder absorption is less well defined. We, therefore, tested the hypothesis that changes in extracellular calcium or in calcium channels would alter gallbladder absorption. New Zealand white rabbit gallbladders were removed, filled with a modified Krebs buffer (Ca2+ = 0.7 mM), and suspended in an oxygenated bath of the same buffer. Water absorption was determined gravimetrically by obtaining serial gallbladder weights at 10-min intervals. After a 40-min control period, the serosal bathing solution was changed to one of four experimental solutions (n = 6 for each group): Ca2+ = 0.25, 0.7, or 1.2 mM or Ca2+ = 0.7 mM plus 0.1 mM verapamil. Absorption was determined during an 80-min experimental period with results expressed as the percentage change in gallbladder absorption compared to that of the control period. The 0.25, 0.7, and 1.2 mM Ca2+ groups did not show a significant change in absorption rate from their respective control rates. However, the verapamil group did demonstrate a significant (P less than 0.05) decrease in absorption rate of -69 +/- 8% by the end of the experimental period. These data demonstrate that verapamil inhibits gallbladder absorption while changes in serosal calcium concentration have no effect. We conclude that calcium channels and intracellular calcium may play an important role in modulating gallbladder absorption.

Absorption↗

Altered bile composition during cholesterol gallstone formation: cause or effect?

Gallbladder stasis, increased gallbladder absorption, and elevated biliary levels of calcium, hydrogen ion, and bilirubin have been implicated as factors potentially critical to cholesterol crystal precipitation. Previous studies, however, have analyzed bile only when crystals or gallstones have already formed. Therefore, we tested the hypothesis that changes in bile composition are a late effect, occurring only after crystal formation. Adult male prairie dogs were fed a standard nonlithogenic control diet (n = 7) or a lithogenic 1.2% cholesterol diet for 5, 9, or 14 days to cause cholesterol saturation (n = 7), cholesterol monohydrate crystals (n = 7), or gallstones (n = 7). Gallbladder bile was examined microscopically for crystals, and analyzed for ionized calcium, bilirubin, pH, total protein, and biliary lipids. The ratio of gallbladder to hepatic bile radiolabeled cholic acid specific activity (Rsa) was calculated as an index of gallbladder stasis. Cholesterol saturation index was calculated. The results demonstrate that increased gallbladder bile cholesterol saturation and total protein concentration precede cholesterol monohydrate crystal precipitation. However, changes in gallbladder ionized calcium, unconjugated bilirubin, pH, stasis, and absorption were noted only after crystals and gallstones had already formed. These data indicate that alterations in gallbladder bile calcium, bilirubin, pH, stasis, and absorption are not early changes, but occur simultaneously with or after crystal formation. Increased biliary protein, however, which was elevated prior to nucleation, may be an important mediator of cholesterol precipitation in cholesterol-saturated bile.

Animals↗

Cancer of the pancreas. Pylorus-preserving resection of the pancreas.

Pylorus-preserving pancreaticoduodenectomy represents an important advance in the history of pancreatic surgery. The operation can be performed with a low operative mortality and morbidity, is technically easier than the standard Whipple resection, and it minimizes the long-term physiological disturbance to the patient. Clinical and experimental evidence has substantiated the view that preservation of the pylorus reduces the incidence of marginal anastomotic ulceration following pancreatectomy. Although gastric emptying may be prolonged transiently in the immediate postoperative period, this complication is easily managed, and is hardly a frequent long-term problem. PPPD is associated with a lower incidence of enterogastric reflux, dumping and diarrhoea than the classical Whipple operation, and patients who have had PPPD are more likely to regain their preoperative and preillness weight. Initial concerns about the use of PPPD in malignant disease have not been borne out, and should now be considered for curative or palliative resections of lesions in the periampullary region including the head of the pancreas. Present data suggest that PPPD does not compromise the long-term survival in patients with periampullary cancers. There is little doubt that the excellent results reported with this procedure as with other forms of major pancreatic surgery, are not simply related to improvements in surgical technique but to establishment of specialist pancreatic surgery.

Anastomosis, Surgical↗

Management of proximal cholangiocarcinomas by surgical resection and radiotherapy.

Ninety-six patients with proximal cholangiocarcinomas were managed surgically. Fifty-three patients (55 percent) were resected, 39 curatively (41 percent), and 43 (45 percent) underwent palliative stenting. The preoperative placement of Ring catheters and the operative use of silastic transhepatic biliary stents greatly facilitated the surgical management of these lesions. Sixty-three patients (66 percent) also received postoperative radiotherapy. Hospital mortality was 4 percent (four deaths). Hospital mortality was 2 percent after resection (1 of 53 patients) and 7 percent after palliative stenting (3 of 43 patients). All deaths resulted from sepsis. One, 3, 5, and 10-year survivals for the entire group were 49 percent, 12 percent, 5 percent, and 2 percent, respectively. One, 3, 5, and 10-year survivals in the resected group (66 percent, 21 percent, 8 percent, and 4 percent, respectively) were superior to those in the stented group (27 percent, 6 percent, 0 percent, and 0 percent, respectively). Radiotherapy appeared to significantly extend survival in those patients undergoing palliative stenting, but not in those undergoing resection. We conclude that surgical resection of proximal cholangiocarcinomas can be performed safely and that it significantly prolongs survival. Further improvement in long-term survival will depend on advances in adjuvant therapy.

Adenoma, Bile Duct↗

Preoperative assessment of malignant hepatic tumors.

Over a 31-month period, 100 patients with malignant hepatic tumors were preoperatively evaluated with three imaging techniques. The results of intravenously enhanced computed tomography (CT) scan, selective hepatic arterial contrast CT, and magnetic resonance imaging (MRI) were compared with operative findings. A total of 227 lesions were identified, with the sensitivity for tumor detection being arteriographically enhanced CT 94% (p less than 0.01), MRI 70%, and CT 66%. This advantage for arteriographically enhanced CT was most marked for lesions less than 1 cm in diameter (82% versus 20% for MRI and 5% for CT; p less than 0.01). Arteriographically enhanced CT was also most sensitive in assessing tumor margins. MRI was clearly superior to arteriographically enhanced CT or CT in detecting vascular involvement (85% versus 30% and 8%, respectively; p less than 0.01). No imaging technique was sensitive in determining extrahepatic involvement. Arteriographically enhanced CT was also best at predicting the operative procedure. The combination of arteriographically enhanced CT and MRI was the best predictor of true disease. We conclude that both arteriographically enhanced CT and MRI should be used for preoperative assessment of hepatic malignancies.

Adolescent↗

Acute cholangitis.

Cholangitis is an infection of the biliary ductal system that results from the combination of bactibilia and biliary obstruction. Choledocholithiasis has been the leading cause of cholangitis. However, in recent years, especially at tertiary referral centers, nonoperative biliary manipulations, often in patients with unresectable malignancies, have become the most common cause of cholangitis. As a result, the complete triad of fever and chills, jaundice, and abdominal pain, as originally described by Charcot, is now seen less frequently. Most patients still have leukocytosis and abnormal liver function tests, but many patients with indwelling tubes may develop cholangitis without significant jaundice. E. coli, Klebsiella species, and the enterococci remain the most frequently isolated organisms, and anaerobes including Bacteroides fragilis are recovered in 15% to 30% of patients. However, Enterobacter and Pseudomonas species, as well as yeasts, are now being isolated more frequently from patients with indwelling tubes, who often have been treated previously with antibiotics. Computed cholangiography usually is necessary to determine the cause and site of biliary obstruction. In the majority of patients with cholangitis, cholangiography can be delayed until the patient has been afebrile for a minimum of 24 to 48 hours. Initial therapy includes bowel rest, intravenous fluids, and antibiotics. Many antibiotic regimens are now available to cover the gram-negative aerobes, the enterococcus, and the anaerobes that are likely to be causing the biliary infection. The combination of a penicillin and an aminoglycoside has been the gold standard. However, recent studies suggest that the newer broad-spectrum penicillins provide adequate therapy for these patients. Only a small percentage (5%-10%) of patients with toxic cholangitis require emergency biliary decompression. The choice of percutaneous or endoscopic drainage should be made on the basis of the presumed site and cause of obstruction as well as local expertise. The nature of the biliary obstruction may be the most important determinant of outcome. At present, patients with end-stage malignant obstruction account for most of the deaths, whereas approximately 95% of patients survive an episode of cholangitis.

Acute Disease↗

Postoperative bile duct strictures.

Bile duct strictures are an uncommon but serious complication of primary operations on the gallbladder or biliary tree. Most strictures occur as a result of injury to the bile duct during cholecystectomy. In addition, strictures can occur at the site of previous biliary anastomoses for reconstruction of the biliary tree. Most patients with benign bile duct strictures present soon after their initial operation; however, in some cases, presentation is delayed for years. Cholangiography is essential for defining the anatomy of the biliary tree prior to management. In many cases, nonoperative biliary drainage is useful to treat sepsis and biliary fistulas. A number of alternatives exist for elective repair of bile duct strictures. Experience would suggest, however, that a choledochojejunostomy or hepaticojejunostomy performed through a Roux-en-Y limb of jejunum is the preferable management in most cases. Postoperative biliary stenting may be valuable in optimizing the results. Nonoperative management by percutaneous transhepatic or endoscopic balloon dilatation has been reported to be successful in a number of small series. Long-term results are limited, however. Comparative data suggest that surgical repair for benign postoperative strictures is associated with fewer long-term problems and with similar overall morbidity and costs.

Bile Ducts↗

Primary sclerosing cholangitis.

Primary sclerosing cholangitis is a rare disease of unknown etiology. Sclerosis of the bile ducts may actually be the final result of multiple factors such as autoimmune, bacterial, congenital, drug, or viral injury. The most commonly associated diseases are ulcerative colitis and chronic pancreatitis. Except in the earliest stages of the disease, liver histologic findings are not specific. Most patients present with jaundice, pain, and pruritus, although an increasing number of asymptomatic patients with inflammatory bowel disease and abnormal liver function are being identified. Cholangiography is key to the diagnosis and is usually pathognomonic except in the unusual case where primary sclerosing cholangitis is confused with cholangiocarcinoma. Many forms of medical therapy have been tried, including antibiotics, azathioprine, cholestyramine, colchicine, cyclosporine, D-penicillamine, steroids, and ursodeoxycholic acid. To date, none of these medications has been proved to alter the course of this disease. Recent reports of ursodeoxycholic acid trials have been encouraging, but long-term results of ongoing randomized trials have yet to be published. In recent years, balloon dilatation of biliary strictures has been accomplished via endoscopic and percutaneous transhepatic approaches. However, in patients with primary sclerosing cholangitis, these nonoperative manipulations must be done repeatedly, may entail multiple general anesthetics, and are difficult to perform. We believe that a direct surgical approach to the biliary tree with long-term transhepatic stenting is indicated in selected patients with severe hilar or extrahepatic stricturing, persistent jaundice or recurrent cholangitis, and no evidence of cirrhosis. Hepatic transplantation should be reserved for patients with primary sclerosing cholangitis who have well-established cirrhosis and have not responded to other therapeutic measures.

Cholangitis, Sclerosing↗

Cholangiocarcinoma.

The diagnosis of cholangiocarcinoma can now be made with greater rapidity and accuracy. In the clinical setting of obstructive jaundice, a CT scan or sonogram may suggest cholangiocarcinoma if dilated intrahepatic ducts are seen with a nondilated extrahepatic biliary tree. The diagnosis is confirmed by cholangiography, and the tumor is staged by the combination of cholangiography and angiography. If the tumor extensively involves both lobes of the liver or involves the main portal vein or hepatic artery, the lesion is considered unresectable. These patients are best palliated nonoperatively, but they should still have an attempt at a tissue diagnosis, as various other lesions can masquerade as cholangiocarcinoma. In comparison, if the tumor is confined to or is distal to the hepatic duct bifurcation, extends into only one lobe of the liver, or involves only the right or the left portal vein or hepatic artery, the lesion may be resectable, and exploration is indicated. As many as half of all patients explored with curative intent will have a successful resection. Various surgical options are appropriate for patients undergoing tumor resection, depending on the site and extent of the lesion. Similarly, several surgical options are possible for palliation in patients with unresectable cholangiocarcinoma. The role of radiotherapy in the management of cholangiocarcinoma is uncertain. Our results, like those of many other retrospective analyses, suggest that radiotherapy prolongs survival after curative resection as well as after palliative stenting. However, further data from randomized studies are necessary to support or refute this impression. Further studies of adjuvant chemotherapy or hormonal therapy will also be necessary to improve patient survival.

Adenoma, Bile Duct↗