Page 463 - Concise Pathology for Exam Preparation ( PDFDrive )

448 SECTION II Diseases of Organ Systems

• Cholecystoenteric fistula: Formation of a fistula between the gallbladder and the
intestine
• Gallstone ileus: May follow the impaction of a gallstone in the intestine
• Porcelain gallbladder: Scarring of the wall, combined with dystrophic calcification
that transforms the gallbladder into a porcelain-like vessel, visible on standard X-ray
films
• Xanthogranulomatous cholecystitis: The gall bladder may be shrunken and show a
markedly thickened wall as a result of rupture of an RA sinus. Sections from the wall
show chronic inflammatory infiltrate with foamy histiocytes (xanthoma cells).
Q. Write briefly on carcinoma of gallbladder.

Ans. The average age of presentation of carcinoma of gallbladder is 65 years. It is associ-
ated with gallstones in up to 90% of cases; porcelain gallbladder is a high-risk condition.
• Patient presents with abdominal pain, jaundice, anorexia, nausea and vomiting.
• Preoperative diagnosis is based on finding abnormalities in the gallbladder wall on im-
aging studies.
• Grossly carcinoma of the gallbladder may be exophytic or more commonly infiltrative
in nature; the latter usually appears as diffuse thickening of the wall of the gallbladder.
• Most carcinomas are adenocarcinomas (90%); few are squamous or adenosquamous
carcinomas (10%) that arise from areas of squamous metaplasia in chronic cholecystitis
and cholelithiasis.

Q. Write briefly on cholangiocarcinomas.
Ans. Cholangiocarcinoma, a malignancy arising from the biliary tree, is the second most
common tumour of the liver after HCC. It has the following clinicopathological features:
• It usually presents in the fifth to seventh decades and has a male to female ratio of 1:1.
• Risk factors include liver fluke infestation, hepatolithiasis (intrahepatic gallstone forma-
tion), PSC, fibrocystic disease of the biliary tree, hepatitis B and C, NAFLD and exposure
to thorotrast.
• Biliary intraepithelial neoplasias (BillN) are known precursors of cholangiocarcinomas,
which are mainly adenocarcinomas with biliary differentiation.
• May be extrahepatic or intrahepatic; extrahepatic cholangiocarcinomas (two-third of
these tumours) may develop at the hilum (called Klatskin tumours) or more distally.
• The prognosis is poor.
PANCREAS

The pancreas is located in the retroperitoneal space caudal to the stomach. It extends
horizontally from the duodenum on the right to the spleen on the left. It has three parts:
• The head of the pancreas is lying in the duodenal loop in close contact with the wall of
this part of the intestine.
• The body of the pancreas is lying over the aorta and the vena cava.
• The tail of the pancreas abuts onto the spleen.
• Pancreas is a mixed exocrine–endocrine organ.
• The exocrine pancreatic tissue (consists of acini and ducts) accounts for 98% of the
total mass.
• Endocrine parts (islets of Langerhans) are microscopic structures that are more numer-
ous in the tail.
• The terminal portion of the main pancreatic duct (duct of Wirsung) enters the muscular
portion of the duodenal wall, where it meets with the common bile duct forming a com-
mon biliary-pancreatic duct that enters the duodenum at the ampulla of Vater.
• In some persons, the pancreatic duct enters the duodenum separately from the common
bile duct.
• An accessory pancreatic duct (duct of Santorini), emptying into the duodenum, is found
in many persons.

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