MSH2 and endometrial cancer: Since the evidence of activity of immune checkpoint inhibitors in patients with advanced mismatch repair (MMR)-deficient endometrial cancer (10) and considering that Lynch syndrome may account for about 3% of all endometrial cancers (11), it is recommended to screen all endometrial cancer patients with the use of immunohistochemical tests for MLH1, MSH2, MSH6, and PMS2 (12).