Virchows Arch 2022 Mar 19. Epub 2022 Mar 19.
Gynecopathology and Breast Pathology Unit, Department of Woman and Child's Health Sciences and Public Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy.
Herein, we present a morphological, immunohistochemical, and molecular analysis of three cases of endometrial giant cell carcinoma (EGCC) with a literature review. Patient age was 55 to 76 years. The tumors were limited to the uterus and showed dyshesive, bizarre giant cells with numerous atypical mitoses. Minor components were low-grade endometrioid, spindled/myxoid (case nos. 1 and 2), serous (case no. 3), and undifferentiated (all cases). The giant cells were e-cadherin-, cytokeratins/EMA + (focal/multifocal), hormone receptors + (focal/multifocal), vimentin + , p16 + (diffuse), CD68-, α-FP-, β-HCG-, muscle markers-, CD10-, and ERG-. Case no. 3 was p53-abnormal. All cases were mismatch repair-proficient and microsatellite-stable. No POLE mutations were detected. Based on our and previous reports, EGCC is often accompanied by a conventional carcinomatous component (mostly endometrioid) and shows partial loss epithelial markers and negativity for specific differentiation markers. EGCC shows evident similarities to both undifferentiated/dedifferentiated carcinoma and carcinosarcoma and should be managed similarly. Unlike the latter two, EGCC might preferentially derive from "no-specific-molecular-profile" carcinomas.