Primary transitional cell carcinoma (TCC) of the ovary has been recently recognized as a separate subtype of epithelial cancer. It has been proposed that recognition of such tumors is important on clinical grounds because of a favorable response to chemotherapy and an improved patient survival. The authors reviewed the histological and clinicopathologic findings of 58 patients with advanced stage (stages III and IV) ovarian cancer with a view to determining the frequency of TCC and confirming the favorable prognosis. Of these cases, 15 (26%) were reclassified as TCC; 13 were predominantly TCC, and 2 had a mixed pattern with approximately 50% of the tumor being TCC. TCC patients ranged in age from 44 to 70 years of age (mean, 57). Ten of the patients had stage III disease, and five were stage IV. The tumor was unilateral in 2 cases and bilateral in 11 (2 unknown). Tumor size varied between 3 and 23 cm. Of the stage III patients, five were optimally debulked, and five had residual disease. All patients received the same type of chemotherapy. The median overall survival was 28 months. There was no significant difference in the clinical outcome of patients with TCC compared with that of patients with serous carcinomas. These data suggest that TCC does not confer a favorable prognosis or better response rate to chemotherapy.