Clinicopathological Study of Intracholecystic Papillary Neoplasm of the Gall Bladder: a Case Series.

Intracholecystic papillary neoplasm (ICPN) is defined as a grossly visible, mass-forming, non-invasive epithelial neoplasm arising in the mucosa and projecting into the lumen of the gallbladder. Since the northeastern part of India has a high incidence of gall bladder cancer, ICPN being a precursor lesion is important to be diagnosed on biopsies. Nine cases with Intracholecystic papillary neoplasm of the gall bladder were studied. The clinicoradiological findings of these patients, gross and microscopic findings of H&E-stained sections were recorded and immunohistochemistry was done for Ki 67. The median age of diagnosis was 60 years with a male-to-female ratio 1:3.5. The most common presenting symptom was pain abdomen, other symptoms included vomiting, weight loss, and jaundice. Associated gall stones were seen in 6 of the cases. Radiological investigations revealed gall stones in 6 cases, intraluminal mass lesion/polyp was reported in 4 cases. Gross examination of the cases showed a polypoidal lesion in 4 cases, papillary projections from the wall in 2 cases. Focal wall thickening was seen in 2 cases while one case showed diffuse wall thickening. Microscopic examination revealed presence of intracholecystic papillary neoplasm which was associated with invasive adenocarcinoma in 7 out of the nine cases. Histologically, the most common type of ICPN in our study was gastric foveolar type (5 cases) followed by biliary type (3 cases) and intestinal type seen in 1 case. ICPN is a known precursor lesion of gall bladder carcinoma. Our case series is an attempt to add to our knowledge of the clinicopathological features of this entity, particularly in the ethnically distinct and heterogeneous population of northeastern India.