TY - JOUR T1 - Mesonephric-like Differentiation of Ovarian Endometrioid and High-grade Serous Carcinomas: Clinicopathological and Molecular Characteristics Distinct from Those of Mesonephric-like Adenocarcinoma JF - Anticancer Research JO - Anticancer Res SP - 4587 LP - 4601 DO - 10.21873/anticanres.15272 VL - 41 IS - 9 AU - KYUE-HEE CHOI AU - HYUNJIN KIM AU - GO EUN BAE AU - SANG HWA LEE AU - HA YOUNG WOO AU - HYUN-SOO KIM Y1 - 2021/09/01 UR - http://ar.iiarjournals.org/content/41/9/4587.abstract N2 - Background/Aim: Ovarian endometrioid carcinoma (EC) and high-grade serous carcinoma (HGSC) may exhibit various growth patterns and mimic mesonephric-like adenocarcinoma (MLA). We investigated the clinicopathological and molecular features of ovarian carcinomas with mesonephric-like differentiation (MLD). Patients and Methods: We analyzed the electronic medical records and pathology slides of two EC-MLD and three HGSC-MLD patients, and conducted immunostaining and targeted sequencing of their samples. Results: All cases showed architectural diversity, compactly aggregated small tubules and ducts, and eosinophilic intraluminal secretions, indicating the possibility of an ovarian MLA. However, the following histological and immunophenotypical features confirmed the diagnoses of EC-MLD and HGSC-MLD: squamous, tubal, and sertoliform differentiation; serous tubal intraepithelial carcinoma; solid, endometrioid, transitional (SET) feature; solid, transitional, endometrioid, mucinous-like (STEM) feature; diffuse expression of hormone receptors and Wilms tumor 1; mutant p53 immunostaining pattern; and wild-type v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog gene. Conclusion: A subset of ovarian ECs and HGSCs can display MLD and mimic an MLA. A thorough histological examination combined with ancillary tests is crucial to differentiate between these ovarian neoplastic entities. ER -