Expression of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2/neu in gallbladder carcinoma in North Indian population

Background: Gallbladder carcinoma (GBC) although rare is most frequent malignant neoplasm of biliary tract system and sixth most common malignancy of digestive tract. GBC is more common in females and there are studies which show expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 neu (HER2/neu) in GBC suggesting possible molecules for targeted therapy, but results are inconsistent. Aims and Objectives: The aim of this study was to find out expression of ER, PR, and HER2/neu in GBC in North Indian population and their possible association with clinicopathological features. Materials and Methods: A total 59 resected cases of GBC diagnosed by histopathological examination were included in the study. Expression of ER, PR, and HER2/neu was accessed by immunohistochemistry method and correlated with various clinicopathological features. Results: ER expression was absent in all GBC cases. PR expression was present in only one case. Positive expression of HER2/neu was present in 13 (22%) cases, in which 12 cases were of conventional adenocarcinoma and one case was of papillary adenocarcinoma. Well and moderately differentiated tumor had significantly higher HER2/neu expression as compared to poorly differentiated tumors (P = 0.001). Pre-obese patients had significantly higher HER2/neu expression as compared to non-obese patients (P = 0.008). Conclusion: In our study, there was no expression of estrogen and PR in GBC in North Indian population. Although small in number, there is a subset of patients who overexpress HER2/neu receptor that may benefit from targeted therapy.