Regarding endometrial carcinoma, the scientific literature reported considerable variations in PD-L1 positivity frequencies (from 0.9% to 44.3%) and evidenced different PD-L1 expression profiles between molecular subclasses, histologic subtypes, and tumoral stage, with the POLE mutant, the MMR deficient, the non-endometrioid types, and the advanced endometrial cancers displaying the highest PD-L1 levels in TCs and ICs, and with the highest CPS. The gene discussed is MRC1; the disease is endometrial cancer.