Article Text
Abstract
Introduction In Endometrial cancer, mismatch repair deficiency (MMRd) is found in up to 30% of cases. Loss of immunohistochemical (IHC) expression of MMR proteins, in endometrial cancer is important and it has various clinical, therapeutic, and prognostic implications. We aimed to investigate the frequency of MMRd in endometrial carcinoma in our population and its association with clinicopathologic features.
Methods A total of 49 cases of primary endometrial carcinoma were included in the study that underwent surgical resections. All slides of these cases were reviewed and representative paraffin fixed tissue blocks were selected for MLH1, MSH2, MSH6, and PMS2 for IHC staining. Clinico-pathological prognostic factors and MMR protein status were documented.
Results Abnormal expression of MMR protein was noted in 16 (32.7%) cases. The most frequent loss of MMR protein was the combined loss of MLH1/PMS2 4(25%) and isolated MSH2 4(25%). MSH2/MSH6 loss were 3(18.8%), MLH1/MSH2 in 2(12.5%) cases. MSH2 was the most frequent MMR protein loss in patients having a family history of malignancy.A significant association of MSI expression was found with the FIGO tumor stage.
Conclusion/Implications There is a considerable frequency of MMRd (33%) status in endometrial cancer in our population. This study demonstrates that MMRP deficiency in endometrial cancer is significantly associated with unfavorable prognostic factors, including higher grade, higher stage, and adnexal involvement. More large-scale studies with genetic testing are required to validate this observation.