The E-Cadherin expression vs. tumor cell proliferation paradox in endometrial cancer.

Abstract

BACKGROUND: E-Cadherin is a putative marker of good prognosis in endometrial cancer. Paradoxically, in a previous study of endometrial carcinoma we found that E-Cadherin is significantly co-expressed with molecular markers of proliferation, usually associated with a worse prognosis in most tumor types. PATIENTS AND METHODS: The expression of estrogen (ER) and progesterone receptors (PR), Ki67, Human Epidermal Growth Factor Receptor 2 (HER-2, c-ERB-B2), p53 and E-Cadherin was studied by means of immunohistochemistry in 126 endometrial carcinoma samples. The results were correlated with patient survival and included in a multivariate model, in order to identify factors independently associated with the patient outcome. RESULTS: E-Cadherin overexpression was associated with a significantly better overall survival in the whole group of patients with endometrial carcinoma (p=0.012), as well as in the group of patients exclusively harboring endometrioid tumors (p=0.004). In a restricted multivariate model, only tumor stage and E-Cadherin expression retained their independent prognostic power, both for the whole group of tumors (p=0.04), as well as for the subgroup of endometrioid carcinomas (p=0.05). CONCLUSION: E-Cadherin is an independent predictor of survival in endometrial carcinoma, regardless of histological variety. Proliferation, on the other hand, does not seem to play a prominent role in this same context. This may explain why E-Cadherin retains its prognostic power, despite being significantly co-expressed with all tested molecular proliferation markers.