Ovarian RASoma With Mesonephric-like Adenocarcinoma and Mixed Mullerian Components: A Case Report With Molecular Analysis Demonstrating Multidirectional Mullerian Differentiation.

Gynecologic carcinomas with RAS mutations may show a wide spectrum of histologic types, including mixed types. We present the case of a 63-yr-old patient diagnosed with an ovarian tumor harboring a mesonephric-like adenocarcinoma in a background of mixed mesonephric-like, mucinous, and endometrioid components. Molecular analysis revealed that all 3 components shared the same clonal KRAS mutation (p.G12A) and chromosome 1q gain. Based on shifts in clonality, copy number gains, and acquisition of an additional mutation, our data suggest that the mucinous component likely constituted the substrate from which the mesonephric-like and endometrioid components arose.