Expression and clinicopathological correlation of Ki-67 in gallbladder carcinoma.

Introduction: Gallbladder cancer is an aggressive cancer with short median survival from the time of diagnosis. Improved understanding of the pathological molecular mechanisms of gallbladder carcinogenesis is important to refine the diagnosis, prognosis, and also to develop novel targeted therapies for patients with advanced Gallbladder cancer (GBC) malignancy. Ki-67 is a marker of cell proliferation and its detection by immunohistochemistry is considered to be an effective method for the detection of prognosis in several tumors. In the present study, we have analyzed expression of immunohistochemical marker Ki-67 in gallbladder carcinoma and its correlation with clinicopathological and radiological parameters.

Materials and methods: This prospective observational study was conducted from December 2017 to July 2020. The patients of newly diagnosed gallbladder cancer were enrolled as per the inclusion and exclusion criteria defined in the study protocol. Contrast-enhanced computer tomography of the chest and abdomen and serum tumor markers such as carbohydrate antigen (CA)-19.9, carcinoembryonic antigen, and CA 125 were done. Immunohistochemical expression of Ki-67 was evaluated on biopsy tissue from the gallbladder mass.

Results: Fifty newly diagnosed patients of carcinoma gallbladder were included in the present study. The correlation was studied between clinicodemographic parameters and Ki-67, but no association was found with age, gender, and symptoms. There was a weak positive correlation between Ki-67 and direct bilirubin, serum glutamic pyruvic transaminase, serum glutamic oxaloacetic transaminase, and alkaline phosphatase (P = 0.094; 0.126; 0.542; and 0.328, respectively). There was a weak positive correlation between body mass index (Kg/m²) and Ki-67, but this correlation was not statistically significant (P = 0.304).

Conclusions: Ki-67 is a marker of proliferation and it correlated with histological differentiation, jaundice and liver function tests, presence of stones, and location of metastases but did not correlate with stage and extent of disease.