Survival of endometrial cancer patients with lymphatic invasion and deficient mismatch repair expression

Abstract Objective This study examines patients under the age of 70 with endometrial cancer and lymphatic invasion or lymph node metastases. Survival of patients with loss of tumor mismatch repair expression is compared to survival of patients with normal mismatch repair expression. Methods This is a retrospective review of patients treated from 1998–2009 for carcinoma of the endometrium. All patients with lymphatic invasion, including lymph node metastases, had immunohistochemical staining of the primary tumor for loss of expression of the mismatch repair genes MLH1, PMS2, MSH6, and MSH2. Overall survival and disease specific survival were compared using Kaplan–Meier plots. Results Sixty-six patients were identified for inclusion; 26 demonstrated loss of mismatch repair expression and 40 demonstrated normal mismatch repair expression. Overall survival and disease specific survival were significantly better in the group with defective mismatch repair expression. Subgroup analysis of FIGO stage 3C patients also showed significantly better survival in patients with deficient mismatch repair expression. Conclusion For patients with endometrial cancer and lymphatic invasion, patients demonstrating loss of mismatch repair expression in the primary tumor appear to have a significantly better survival than patients with normal mismatch repair expression. Further investigation appears warranted to examine a possible role of mismatch repair expression as a prognostic marker for high risk patients with endometrial cancer.