Mucinous cystadenoma and benign mesonephric-like proliferation in the ovary – Further evidence for clonal relationship

• Published in: Pathology, research and practice Vol. 258; p. 155336
• Main Authors: Hiller, Grit Gesine Ruth, Höhn, Anne Kathrin, Krücken, Irene, Monecke, Astrid, Reske, Dennis, Brambs, Christine Elisabeth, Horn, Lars-Christian
• Format: Journal Article
• Language: English
• Published: Germany Elsevier GmbH 01.06.2024
• Subjects: Biomarkers, Tumor - analysis; Cell Proliferation; Cystadenoma, Mucinous - genetics; Cystadenoma, Mucinous - pathology; Female; Humans; KRAS-mutation; Mesonephric-like; Mucinous cystadenoma; NGS; Ovarian Neoplasms - genetics; Ovarian Neoplasms - pathology; Ovary; Ovary - pathology; Proto-Oncogene Proteins p21(ras); Transdifferentiation; Ovary; Mesonephric-like; NGS; KRAS-mutation; Transdifferentiation; Mucinous cystadenoma
• ISSN: 0344-0338; 1618-0631
• DOI: 10.1016/j.prp.2024.155336

Mesonephric-like adenocarcinomas rarely occur in the uterus and the ovary. Benign mesonephric-like (ML) proliferations and hyperplasia have been described solely within the ovary. Pathogenetic data are very limited. We report a case with microscopic focus of benign ML-proliferation in association with mucinous cystadenoma in the ovary. The immunophenotype was distinct (mucinous tumor: focal weak nuclear positivity for PAX-8, CK 7, patchy cytoplasmic positivity for p16 and negativity for estrogen receptor, CD 10, TTF-1, p53 wildtype; mesonephric component: diffusely positive for PAX-8, CK 7, luminal CD 10, TTF-1, focal staining for estrogen receptor, patchy cytoplasmic for p16, p53 wildtype). On NGS-analysis there was clonal mutation of KRAS p.G12C. The data provide additional evidence for the concept of transdifferentiation (Müllerian tissue representing Wolffian/mesonephric features on histology and immunostaining) within the pathogenesis of mesonephric proliferation of the female genital tract and demonstrate the clonal relationship between these distinct morphologic components.