Cytology of granulosa cell tumor of the ovary.

Granulosa cell tumor of the ovary may create a diagnostic challenge in cytologic preparations. Our experience with needle aspiration material, ascitic fluid, and peritoneal washings indicates that in fluids, despite some similarity between the tumor cells and reactive mesothelial cells, a correct diagnosis can be achieved by careful examination. The paucity of the cytoplasm and an intense indentation of nuclear membrane are the most helpful features in distinguishing the granulosa cells from mesothelial cells. The literature is reviewed, and the controversies regarding needle aspiration of ovarian neoplasms are discussed.