Incidental gallbladder carcinoma: value of routine histological examination of cholecystectomy specimens

Cholecystectomized specimens are one of the frequently encountered specimens in daily routine histopathological work in the pathology department. With the expectation that most of the gallbladder specimens harbor benign disease, it is at times surprising to find occult malignancy. This study aims to find out the frequency of primary gallbladder carcinoma and incidental primary carcinoma, detected during routine histological examination of gallbladder specimen that were submitted in pathology department of Nepal Medical College Teaching Hospital (NMCTH) as well as to assess the need of histopathological examination of cholecystectomy specimens. Retrospective study was done in total 668 cases of cholecystectomies specimens submitted in NMCTH histopathology department during 5 yrs of duration from Jan 2003 to Dec 2007. There were total 22 cases of primary gallbladder carcinoma and 2 cases of metastatic cholangiocarcinoma in gallbladder. The incidence rate of primary malignancy was 3.3% and was commonly found in female at 7th decade of their life. Adenocarcinomas were the most common histological type with poor differentiation and diagnosed frequently at stage IIA. The rate of incidental primary carcinoma of gallbladder was 1.4%, detected commonly at stage I. Combined preoperative and intraoperatively, only 55.0% of histologically proven gallbladder malignancies were correctly identified. Intraoperative findings of incidental carcinomas included thickened GB (3 cases), distended GB (2 cases), GB polyp (1 case) and no obvious abnormality were mentioned in 3 cases. Therefore, every cholecystectomy specimen should be examined histopathologically to detect possible incidental carcinomas.