Tumor-infiltration of T-lymphocytes is inversely correlated with clinicopathologic factors in endometrial adenocarcinoma

OBJECTIVE The aim of this study was to determine the distribution of T-lymphocytes and their relationship with clinicopathologic factors in endometrial carcinoma. METHODS Samples were collected from 89 patients with endometrial endometrioid adenocarcinoma treated in Pusan National University Hospital from 2004 to 2011. Normal endometrial tissues were obtained from 30 hysterectomized women with benign adnexal masses and served as controls. Paraffin-embedded sections were immunohistochemically stained for CD8 (cytotoxic) and CD4 (helper) T-lymphocytes. The relationship of these cells with stage, histological grade, myometrial invasion, and lymph node metastasis was analyzed. RESULTS The proportion of CD8+ and CD4+ lymphocytes in the endometrial endometrioid adenocarcinoma tissues was 67.4% (60/89) and 44.9% (40/89), respectively, which was significantly higher (P<0.05) than in the control group. The extent of CD8+ lymphocyte expression was negatively correlated with histologic grade, myometrial invasion, and lymph node metastasis. The proportion of infiltration of the CD4+ lymphocytes was negatively correlated with histologic grade and myometrial invasion. CONCLUSION The high rate of infiltration of T-lymphocytes was negatively correlated with histologic grade, myometrial invasion, and lymph node metastasis. Our findings suggest that tumor-infiltrating T-lymphocytes may be used as pathologic prognostic factors in endometrial carcinoma.