Page 659 - Textbook of Pathology, 6th Edition

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Figure 21.44 Chronic cholecystitis, microscopic appearance. There is penetration of epithelium-lined spaces into the gallbladder wall (Rokitansky-
Aschoff sinus) in an area. There is subepithelial and subserosal fibrosis and hypertrophy of muscularis. Mononuclear inflammatory cell infiltrate is
present in subepithelial and perimuscular layers.

a constant dullache in the right hypochondrium and 1. Cholelithiasis and cholecystitis. The most significant CHAPTER 21
epigastrium and tenderness over the right upper abdomen. association of cancer of the gallbladder is with cholelithiasis
Nausea and flatulence are common. Biliary colic may and cholecystitis, though there is no definite evidence of
occasionally occur due to passage of stone into the bile ducts. causal relationship. Cholelithiasis and cholecystitis are
Cholecystography usually allows radiologic visualisation of present in about 75% cases of gallbladder cancer. On the other
the gallstones. hand, incidence of documented gallbladder cancer in the
presence of cholelithiasis and cholecystitis is about 0.5% only.
Porcelain gallbladdder is particularly likely to become
TUMOURS OF BILIARY SYSTEM
cancerous.
BENIGN TUMOURS 2. Chemical carcinogens. A number of chemical
carcinogens structurally similar to naturally-occurring bile
Benign tumours such as papilloma, adenoma, adenomyoma, acids have been considered to induce gallbladder cancer.
fibroma, lipoma, myxoma, and haemangioma have been These include methyl cholanthrene, various nitrosamines
described in the biliary tract but all of them are exceedingly and pesticides. Workers engaged in rubber industry have
rare. Adenomyoma is more common benign tumour than the higher incidence of gallbladder cancer.
rest. All these tumours resemble their counterparts in The Liver, Biliary Tract and Exocrine Pancreas
morphology elsewhere in the body. 3. Genetic factors. There is higher incidence of cancer of
the gallbladder in certain populations living in the same
MALIGNANT TUMOURS geographic region suggesting a strong genetic component
in the disease. Japanese immigrants and Native Americans
Carcinoma of the gallbladder and carcinoma of the bile ducts of the South-Western America have increased frequency
and ampulla of Vater are among the more frequent malignant while American Indians and Mexicans have lower incidence.
tumours of the biliary tract.
4. Miscellaneous. Patients who have undergone previous
Carcinoma of the Gallbladder surgery on the biliary tract have higher incidence of
subsequent gallbladder cancer. Patients with inflammatory
Primary carcinoma of the gallbladder is more prevalent than bowel disease (ulcerative colitis and Crohn’s disease) have
other cancers of the extrahepatic biliary tract. Like high incidence of gallbladder cancer.
cholelithiasis and cholecystitis, it is more frequent in women
than in men (ratio 4:1) with a peak incidence in 7th decade MORPHOLOGIC FEATURES. The commonest site is the
of life. It may remain undetected until the time it is widely fundus, followed next in frequency by the neck of the
spread and rendered inoperable. gallbladder (Fig. 21.45).
Grossly, cancer of the gallbladder is of 2 types—infil-
ETIOLOGY. A number of etiologic factors have been
implicated. trating and fungating type (Fig. 21.46):