Objective: Ovarian surface epithelial tumors rarely have heterologous elements including bone or cartilage that may appear histologically benign or malignant. There are a few case reports in the literature of ovarian tumors containing chondromatous areas.
Case: We report a clear cell carcinoma of the bilateral ovary showing chondromatous differentiation in a 56-year-old woman. Histopathologic study of the specimen showed clear cell carcinoma with many small foci of chondromatous differentiation. Immunohistochemical studies demonstrated positivity for S-100 confirming the diagnosis. The patient was alive with disease on chemotherapy for 16 months.
Conclusion: A rare case of benign appearing chondromatous differentiation in an ovarian clear cell carcinoma of the ovary is described, and the significance of this finding is discussed.