Ovarian Carcinosarcoma With Heterologous Chondrosarcomatous Differentiation: A Case Report and Review of Literature.

Ovarian carcinosarcoma is a rare and aggressive malignancy characterized by the coexistence of epithelial and mesenchymal components. It poses considerable diagnostic and therapeutic difficulties largely due to its high propensity for peritoneal dissemination and unfavorable prognosis. We report the case of a 58-year-old woman presenting with progressive abdominal distension and pelvic pain. Imaging revealed a left ovarian mass associated with ascites and diffuse peritoneal carcinomatosis. Cytological analysis of ascitic fluid demonstrated malignant cells and histopathological examination of omental and peritoneal biopsies showed a biphasic tumor, composed of a high-grade serous carcinoma component and a heterologous chondrosarcomatous component. Immunohistochemistry revealed positivity for CK7, WT1, P16, and diffuse p53 expression, supporting a high-grade serous epithelial origin, while CK20 was negative. The diagnosis of ovarian carcinosarcoma with heterologous differentiation was retained. Given the advanced stage, the patient was considered for platinum-based chemotherapy. This case highlights the diagnostic challenges and histopathological features of ovarian carcinosarcoma. The current therapeutic regimen for carcinosarcoma is still based on tumor cytoreduction and platinum-containing chemotherapy; research on targeted therapy is still in progress.