Ovarian Endometrioid Adenocarcinoma: Incidence and Clinical Significance of the Morphologic and Immunohistochemical Markers of Mismatch Repair Protein Defects and Tumor Microsatellite Instability

"Ovarian cancer, particularly endometrioid (cell type)adenocarcinoma, is also associated with Lynch syndrome.....Overall, 10% of tumors had abnormal MMR protein status, defined as complete immunohistochemical loss of expression of MLH1, MSH2, MSH6, and/or PMS2.....Concurrent uterine tumor was present in 5/7 patients whose ovarian tumor had abnormal MMR/MSI.......Although abnormal MMR/MSI did not carry prognostic value in this study, it did predict the involvement of the uterus by the tumor. Thus, in patients with ovarian endometrioid adenocarcinoma who undergo uterus-sparing surgery, abnormal MMR/MSI should prompt further diagnostic evaluation of the endometrium for tumor."