Concerning the background endometrium, two cases showed partial loss of MLH1 and PMS2, corresponding to adjacent EC lesions, suggesting that MMR deficiency may already be present in the background endometrium.
Hereditary brain tumor with a homozygous germline mutation in PMS2: pedigree analysis and prenatal screening in a family with constitutional mismatch repair deficiency (CMMRD) syndrome.
Mismatch repair deficiency is strongly associated with responsiveness to anti-PD-1 in other cancers and can be detected using immunohistochemistry for MLH1, MSH2, MHS6, and PMS2.
Herein, we investigate the clinical meaning of MMR deficiency in breast cancer by immunohistochemical assessment of MSH2, MSH6, MLH1 and PMS2 on a large series of breast cancers linked to detailed biomarker and long-term outcome data.