Villous Adenoma

Adenomatous polyps are, by definition, neoplastic. Although benign, they are the direct precursors of adenocarcinomas and follow a predictable cancerous temporal course unless interrupted by treatment. They can be either pedunculated or sessile. Polyps are generally asymptomatic but may occasionally ulcerate and bleed; uncommonly, they may result in obstruction if very large. Adenomas are divided into 3 subtypes based on histologic criteria, as follows: (1) tubular, (2) tubulovillous, and (3) villous. According to World Health Organization (WHO) criteria, villous adenomas are composed of greater than 80% villous architecture. Tubular adenomas are encountered most frequently (80-86%). Tubulovillous adenomas are encountered less frequently (8-16%), and villous adenomas are encountered least frequently (5%).
See the images below.
Endoscopic view of a sessile polyp, which histology studies revealed to be a villous adenoma. Courtesy of H. Chaun, MD. Endoscopic view of a sessile polyp histologically determined to be a villous adenoma. Courtesy of R. Enns, MD. Histology of villous adenoma. Fingerlike projections stretching from the surface of a polyp downward with minimal branching. Courtesy of D. Owen, MD. Histology of villous adenoma. Low-grade dysplasia with loss of mucin, prominent nucleoli, and hyperchromatic and elongated cells. Courtesy of D. Owen, MD.
Villous adenomas are associated more often with larger adenomas and more severe degrees of dysplasia. These adenomas occur more frequently in the rectum and rectosigmoid, although they may occur anywhere in the colon. They generally are sessile structures that appear as velvety or cauliflowerlike projections. Although rare, villous adenomas of the duodenum and the small bowel, particularly at the ampulla, can occur. Villous adenomas are of concern primarily because of the risk of malignant transformation (approximately 15-25% overall but higher once >2 cm).
The primary focus of this article is colonic villous adenomas. Where appropriate, certain aspects of small bowel villous adenomas are addressed

Posted 3rd February by

 

Bile duct stricture (biliary stricture) is an uncommon but challenging clinical condition that requires a coordinated multidisciplinary approach involving gastroenterologists, radiologists, and surgical specialists. Unfortunately, most benign bile duct strictures (biliary strictures) are iatrogenic, resulting from operative trauma (see images below). Bile duct strictures (biliary strictures) may be asymptomatic but, if ignored, can cause life-threatening complications, such as ascending cholangitis liver abscess, and secondary biliary cirrhosis.
Focal intrahepatic benign bile duct stricture after cholecystectomy. Percutaneous transhepatic cholangiogram with balloon dilation of a postoperative bile duct stricture.
However, not all bile duct strictures (biliary strictures) are benign.  is the most common cause of malignant biliary strictures (see images below). Most of these patients die of complications of tumor invasion and metastasis rather than from the bile duct stricture (biliary stricture) per se. Nonetheless, both benign and malignant bile duct strictures can be associated with distressing symptoms and excessive morbidity^]
Endoscopic retrograde cholangiopancreatographic cholangiogram demonstrating an isolated mid-hepatic duct stricture as a result of pancreatic cancer. Focal bile duct stricture as a result of pancreatic cancer in the head of the pancreas.
For excellent patient education resources, visit eMedicine's and . Also, see eMedicine's patient education articles and .

Posted 3rd February by

Choledochal Cysts

 are congenital anomalies. These cystic dilatations of the biliary tree can involve the extrahepatic biliary radicles, the intrahepatic biliary radicles, or both. In 1723, Vater and Ezler published the anatomical description of a . Douglas wrote the clinical report involving a 17-year-old girl presenting with , fever, intermittent abdominal pain, and an abdominal mass The patient died a month after an attempt at percutaneous drainage of the mass. (See image below.)
Operative specimen of type I choledochal cyst. In 1959, Alonzo-Lej produced a systematic analysis of choledochal cysts, reporting on 96 cases. He devised a classification system, dividing choledochal cysts into 3 categories, and outlined therapeutic strategies. Todani has since refined this classification system to include 5 categories. This article reviews the incidence, pathophysiology, diagnosis, and management of choledochal cysts.

Recent research

In a retrospective analysis of 32 children and 47 adults with choledochal cysts, Shah et al investigated the differences between these 2 groups with regard to the presentation, management, and histopathology of, as well as the outcomes related to, these lesionsThe following were among the authors' findings:

• A history of biliary surgery, early postoperative complications, and late postoperative complications occurred, respectively, 5.1, 5.4, 6.4, 2.0, and 3.3 times more frequently in adults than they did in children.
• The classic triad of abdominal pain, jaundice, and a palpable right upper quadrant abdominal mass occurred 6.7 times more frequently in children than in adults.
• Fibrosis of the cyst wall was peculiar to children.
• Signs of inflammation and hyperplasia were primarily seen in adults.
• Long-term complications occurred in 29.7% of adults but in only 9.3% of children.

The authors concluded that because of such differences, choledochal cysts in children should be considered separate entities from those in adults.

Posted 3rd February by

Cholelithiasis

Cholelithiasis is the medical term for gallstone disease. Gallstones are concretions that form in the biliary tract, usually in the gallbladder (see the image below).
Cholelithiasis. A gallbladder filled with gallstones (examined extracorporally after laparoscopic cholecystectomy [LC]).
Gallstones develop insidiously, and they may remain asymptomatic for decades. Migration of a a gallstone into the opening of the cystic duct may block the outflow of bile during gallbladder contraction. The resulting increase in gallbladder wall tension produces a characteristic type of pain . Cystic duct obstruction, if it persists for more than a few hours, may lead to acute gallbladder inflammation ().
refers to the presence of one or more gallstones in the common bile duct. Usually, this occurs when a gallstone passes from the gallbladder into the common bile duct (see the image below).
Common bile duct stone (choledocholithiasis). The sensitivity of transabdominal ultrasonography for choledocholithiasis is approximately 75% in the presence of dilated ducts and 50% for nondilated ducts. Image courtesy of DT Schwartz.
A gallstone in the common bile duct may impact distally in the ampulla of Vater, the point where the common bile duct and pancreatic duct join before opening into the duodenum. Obstruction of bile flow by a stone at this critical point may lead to abdominal pain and jaundice. Stagnant bile above an obstructing bile duct stone often becomes infected, and bacteria can spread rapidly back up the ductal system into the liver to produce a life-threatening infection called ascending cholangitis. Obstruction of the pancreatic duct by a gallstone in the ampulla of Vater also can trigger activation of pancreatic digestive enzymes within the pancreas itself, leading Chronically, gallstones in the gallbladder may cause progressive fibrosis and loss of function of the gallbladder, a condition known as chronic cholecystitis. Chronic cholecystitis predisposes to  .
Ultrasonography is the initial diagnostic procedure of choice in most cases of suspected gallbladder or biliary tract disease (see Workup).
The treatment of gallstones depends upon the stage of disease. Asymptomatic gallstones may be managed expectantly. Once gallstones become symptomatic, definitive surgical intervention with excision of the gallbladder (cholecystectomy) is usually indicated. Cholecystectomy is among the most frequently performed abdominal surgical procedures (see Treatment). Complications of gallstone disease may require specialized management to relieve obstruction and infection

Emphysematous Cholecystitis

Emphysematous cholecystitis, known less commonly as clostridial cholecystitis, is an acute infection of the gallbladder wall caused by gas-forming organisms (eg, Clostridium or Escherichia coli) that is generally considered a surgical emergency. An infrequent, insidious, and rapidly progressive form of acute cholecystitis, emphysematous cholecystitis is characterized by early gangrene, perforation of the gallbladder and high mortality. Although this condition develops in approximately 1% of all cases of acute cholecystitis, compared with typical acute cholecystitis, emphysematous cholecystitis is associated with much higher rates of gangrene and perforation of the gallbladder and significantly increased rates of mortality (15-25%).
An estimated 500,000 cholecystectomies are performed per year in the United States. Assuming all patients with emphysematous cholecystitis come to surgery, this would indicate that 5000 cholecystectomies are performed per year for emphysematous cholecystitis. Although the number of patients who are treated successfully without surgery is certainly small, the number of patients who die without surgery is unknown.
Usually, the diagnosis is made by the radiographic presence of air within the gallbladder wall or lumen. Elderly males, especially diabetics, are particularly susceptible to clostridial cholecystitis (emphysematous cholecystitis). The computed tomography (CT) scan below shows a patient with emphysematous cholecystitis.
Emphysematous cholecystitis in a 47-year-old man with diabetes who experienced abdominal pain. This computerized tomography scan shows gas within the wall of the gallbladder (horizontal arrow) as well as within the lumen of the gallbladder (vertical arrow). Radiograph courtesy of Helen Morehouse, MD.

Gallbladder Tumors

Gallbladder tumors are recognized with increasing frequency due to improvements in imaging techniques and increased utilization of these studies. Approximately 5% of patients evaluated with ultrasonography for abdominal pain will have a gallbladder polyp. Cancer of the gallbladder is uncommon, although it is the fifth most common gastrointestinal malignancy. The size of a gallbladder polyp is generally the strongest predictor of malignant transformation. (See image below.)
A schematic drawing of the extent of lymphadenectomy for gallbladder cancer, especially when the extrahepatic biliary tree is resected.

Benign lesions

Benign lesions of the gallbladder are relatively common, but only adenomatous polyps are considered to have malignant potential. Although ultrasonography can be useful in evaluating these lesions, considerable difficulty may be encountered in establishing the diagnosis preoperatively.

Cholesterol polyps

Cholesterol polyps account for approximately 50% of all polypoid lesions of the gallbladder.
These lesions are thought to originate from a defect in cholesterol metabolism. They appear as yellow spots on the mucosal surface of the gallbladder and are identified histologically as epithelial-covered macrophages laden with triglycerides and esterified sterols in the lamina propria of the mucosal layer of the gallbladder.
As a rule, cholesterol polyps exist as multiple lesions and are usually less than 10 mm. Cholesterol polyps are generally asymptomatic.

Inflammatory polyps

These lesions result from chronic inflammation. They extend into the gallbladder lumen by a narrow vascularized stalk.

Adenomyomatosis

Adenomyomatosis is characterized by extensions of Rokitansky-Aschoff sinuses through the muscular wall of the gallbladder. Ultrasonography reveals a thickened gallbladder wall with intramural diverticula. Although adenomyomatosis is generally considered a benign condition, serial evaluation with ultrasonography is indicated to rule out enlarging adenomatous polyps and gallbladder cancer. Some authors have reported gallbladder cancer occurring in localized adenomyomatosis and have suggested a more aggressive approach to the benign lesions.

Adenomatous polyps

Adenomatous polyps are benign epithelial neoplasms with malignant potential. Papillary adenomas grow as pedunculated, complex, branching tumors projecting into the gallbladder lumen. Tubular adenomas arise as a flat, sessile neoplasm. Consequently, it can be difficult to distinguish some adenomas from other gallbladder polyps by ultrasonography. Like many gastrointestinal tumors, an adenoma-carcinoma sequence is generally thought to occur in these lesions.

Other lesions

Other rare, benign lesions found in the gallbladder include fibromas, leiomyomas, lipomas, hemangiomata, granular cell tumors, and heterotropic tissue, including gastric, pancreatic, and intestinal epithelium.

Malignant lesions

The incidence of gallbladder cancer is 1.2 cases 100,000 persons in the United States; the frequency is much higher in Mexican Americans and Native Americans, although the greatest incidence is found in the indigenous peoples of the Andes Mountains, in northeastern Europeans, and in Israelis. The female-to-male ratio for gallbladder cancer is about 3:1; incidence of the disease peaks in the seventh decade of life.^[1]
The most common risk factor for gallbladder cancer is gallstones, which are present in 75%-90% of gallbladder cancer cases. The size of the gallstones plays a role in the risk of developing of gallbladder cancer. Gallbladders containing gallstones that are greater than 3 cm in diameter have a 10-fold greater risk for developing malignancy than do those containing gallstones that are 1 cm in diameter. Causality is difficult to establish, but other chronic inflammatory conditions, such as cholecystoenteric fistula, primary sclerosing cholangitis, pancreaticobiliary maljunction, and chronic infection with Salmonella typhi, have also been associated with an increased risk of gallbladder cancer.
Modern series report about a 10% incidence of gallbladder cancer in porcelain gallbladders (in which the gallbladder wall is calcified), a much lower rate than that reported in older series. Stippled calcification of the mucosa is thought to carry a higher risk of gallbladder cancer than does generalized calcification of the gallbladder wall.^{[2, 3]} Based on these associations, chronic inflammation is postulated to be involved in the pathogenesis of gallbladder cancer.
Gallbladder cancer is often discovered incidentally during a workup for gallstone disease, and about 50% of gallbladder cancer cases are diagnosed incidentally in cholecystectomy specimens. Unfortunately, about 35% of patients have distant metastases at the time of diagnosis.
Histologically, adenocarcinoma is found in 90% of gallbladder cancer cases, and squamous cell carcinoma is found in 2% of cases. Rare types of gallbladder cancer include sarcoma, adenosquamous carcinoma, oat cell carcinoma, carcinoid, lymphoma, melanoma, and metastatic tumors. A number of histologic subtypes of adenocarcinoma have been described, but papillary adenocarcinoma represents about 5% of gallbladder cancers; it tends to be well-differentiated and carries a more favorable prognosis. (See images below.)
Sagittal ultrasonogram in a 71-year-old woman. This image demonstrates heterogeneous thickening of the gallbladder wall (arrows). The diagnosis was primary papillary adenocarcinoma of the gallbladder. A transaxial enhanced computed tomography (CT) scan of a 60-year-old man with right upper quadrant pain shows a partially calcified gallbladder (arrow). At laparotomy and histology, an infiltrating

Gastroenterology

A diverse spectrum of disease affects the biliary system, often presenting with similar clinical signs and symptoms.
A normal postcholecystectomy cholangiogram. Biliary disease. In this patient with persistent elevation of liver-associated enzymes, the contrast entering the biliary ductal system preferentially enters the cystic duct. Biliary disease. Even when the catheter is advanced to the proximal common hepatic duct, contrast dye preferentially fills the cystic duct and gallbladder rather than allowing visualization of the intrahepatic ductal system. Biliary disease. In this image, the common bile duct is occluded with a balloon-tipped catheter. Contrast fills the intrahepatic ductal system to reveal diffuse intrahepatic sclerosing cholangitis.

Dermatitis

Berloque dermatitis obtains its name from the German word berlock or the French berloque, meaning trinket or charm. Rosenthal^[1] coined the term in 1925 to describe pendantlike streaks of pigmentation on the neck, face, arms, or trunk. He suspected they were due to fluid droplets, unaware that Freund^[2] in 1916 had described hyperpigmented macules due to sun exposure after the application of eau de cologne. The phototoxic ingredient causing the pigmentation proved to be bergapten, a component of oil of bergamot, derived from the rind of Citrus bergamia, the bergamot lime. Several cases were reported in the 1950s and 1960s following increased use of perfumes containing oil of bergamot and the passion for sunbathing. Since the introduction of artificial oil of bergamot and the reduced use of the natural product in perfumes, berloque dermatitis has become rare. Note the image below.
Hyperpigmented streaks on the dorsa of hands of a patient with bergapten phototoxicity