Cytology of ascitic fluid in a patient with metastasizing malignant Brenner tumor of the ovary. A case report.

BACKGROUND Transitional cell ("Brenner") tumors represent about 2% of all ovarian neoplasms. Brenner tumors are almost always benign. Malignant Brenner tumors of the ovary resemble urothelial carcinomas and are extremely rare. CASE A 77-year-old, white female presented with malignant Brenner tumor in both ovaries as well as lung and abdominal metastases. The cytology of the ascitic fluid revealed many activated mesothelial cells and three-dimensional cell clusters arranged in a papillary pattern. The round to oval nuclei displayed mild anisokaryosis and hyperchromasia but had a quite evenly dispersed opaque or finely granular nucleoplasm. Enfoldings of the nuclear membrane gave them the appearance of so-called coffee bean nuclei. The cytoplasm stained light bluish. CONCLUSION Knowledge of the cytologic features of ascitic fluid might allow a preoperative diagnosis of malignant, or at least proliferating, ovarian Brenner tumor.