Background: Gallbladder carcinoma is a relatively rare malignancy with a poor prognosis. We have often encountered patients in whom the course of their disease differed substantially from what would be predicted based on their clinical staging, which highlights the needs to consider additional predictive factors. Gallbladder carcinoma occurs more frequently in women than men, yet expression of the estrogen receptor (ER) and progesterone (PR) have not been studied. We applied an immunohistochemical stain to examine the expression of ER(alpha), ER(beta), and PR in radically resected gallbladder carcinoma.
Material and methods: We immunohistochemically investigated 30 specimens of gallbladder adenocarcinoma tissues using ER(alpha), ER(beta), and PR antibodies.
Results: Adenocarcinoma of gallbladder is negative for both ER(alpha) and PR. However, 22 of 30 cases (73.3%) were confirmed positive for ER(beta), which was significantly correlated with tumor differentiation. Five-year survival rates of ER(beta) positive and negative patients were 53.3% and 31.1%, respectively (P = 0.034). In multivariate analysis, only a low proportion score of ER(beta) status was a statistically significant factor (P = 0.033).
Conclusions: Evaluation of ER(beta) expression in gallbladder carcinoma may be an important factor in identifying a poor prognostic group of gallbladder carcinoma.