Fig. 2. A combination of immunohistochemical and mutational analysis may aid in the distinction of sporadic high-grade TP53-mutant endometrial carcinomas of serous endometrial and FIGO grade 3 endometrioid histologic subtypes.
Histologic features characteristic of MSI endometrial cancers or endometrial carcinomas harboring POLE hotspot mutations include enrichment in tumor-infiltrating lymphocytes and/or peri-tumoral lymphocytes, among others. *DNA MMR markers may be limited to MLH1 immunohistochemistry and/or MLH1 promoter methylation analysis. DNA MMR, DNA mismatch repair; IHC, immunohistochemistry; MSI, microsatellite instability.