Prognostic significance of CD3+ tumor-infiltrating lymphocytes in ovarian carcinoma

Abstract

Objective. Epithelial ovarian cancer (EOC) is the most common cause of death among gynecological malignancies in Europe and North America. Although the presence of tumor-infiltrating mononuclear cells has been documented in EOC, the association of tumor-infiltrating mononuclear cells with clinical outcome remains controversial. The aim of the present study was to investigate the prognostic significance of CD3+ tumor-infiltrating T lymphocytes (TIL) on overall survival of EOC patients. Methods. We evaluated retrospectively by immunohistochemistry the distribution of CD3+ TIL in tumor specimens of 116 EOC patients. The expression of estrogen and progesterone receptors, Ki-67, DNA topoisomerase IIα, p21, p53, HER-2/neu, bax and bcl-2 was also evaluated by immunohistochemistry. The prognostic significance of CD3+ TIL and other immunohistochemical and clinical parameters was evaluated with log-rank test. Multivariate analysis was performed using the Cox regression. Results. CD3+ TIL were observed in all tumor samples, both in cancer stroma and within cancer epithelium (intraepithelial TIL). The median counts of stromal TIL and intraepithelial TIL were 338 lymphocytes/mm 2 (range 81–2094 lymphocytes/mm 2) and 125 lymphocytes/mm 2 (range 7–481 lymphocytes/mm 2), respectively. In univariate analysis, age, stage, grade, presence of residual tumor, expression of progesterone receptors, Ki-67, DNA topoisomerase IIα and intraepithelial CD3+ TIL count were significant predictors of overall survival. On multivariate analysis, only the presence of residual tumor, stage, expression of progesterone receptors and intraepithelial CD3+ TIL count were found to be significant independent predictors of overall survival. Conclusion. Present data indicate that the intraepithelial CD3+ TIL count is a significant prognostic factor in EOC.