Inactivation of tumor suppressor gene pten in early and advanced gallbladder cancer

Background: PTEN is a tumor suppressor gene that regulates the PTEN/PI3k/AKT/mTOR pathway, which is frequently altered in human cancers including gallbladder cancer (GBC). To determine the frequency of PTEN expression in GBC and to establish its relation to clinical and morphological parameters and survival in GBC. Methods: The immunohistochemical expression of PTEN was studied in 108 GBC. All the cases included areas of non-tumor mucosa adjacent to the tumor. Results: The group was comprised of 108 patients, 91 women (84.3 %) and 17 men (15.7 %) with an average age of 65.2 years (SD +/- 12.3 years). Thirty-five cases (33 %) were early carcinomas (EC) and the remaining 73 (67 %) were advanced cases (AC). All the internal controls were positive (moderate or intense in 96.3 %). Only in three AC (4.1 %) was there a complete absence of PTEN immunohistochemical expression. There were no significant differences in relation between PTEN expression and tumor infiltration or degree of differentiation. The three patients with PTEN inactivation died before 10 months; however, the other patients with AC had a survival of 53 % at 10 months. Discussion: Loss of PTEN expression was observed in 4.1 % of the advanced GBC. All the patients with this alteration died before 10 months. PTEN inactivation could be a rare event, but with a poor prognosis in advanced GBC.