Fine-needle aspiration cytology of metastatic ovarian carcinoma to the breast.

Metastatic ovarian carcinoma to the breast is rare. It represents a diagnostic challenge to the cytologist. It usually signifies a progressive widespread metastatic ovarian tumor with a poor prognosis. This report evaluates the breast fine-needle aspiration (FNA) cytomorphologic features of six cases of metastatic ovarian carcinoma and compares them to those reported in the literature. The cytologic features included hypercellularity, abundant papillary fragments, and necrotic background. The tumor cells showed high nuclear/cytoplasmic ratio, anisonucleosis, prominent nucleoli, and psammoma bodies in cases of serous papillary carcinoma. In addition, the clear-cell carcinoma had prominent finely vacuolated and clear cytoplasm, multinucleated giant cells, and papillary fragments with hobnail nuclei. Recognition of these unusual patterns in a breast FNA cytology should raise the suspicion of a metastatic ovarian tumor. Direct comparison between the breast FNA cytology and the original primary ovarian tumor should confirm the diagnosis. The proper diagnosis of metastatic ovarian cancer to the breast will prevent unnecessary surgical treatment and ensure the appropriate therapy.