The authors report 88 cases of ovarian carcinoma containing areas of transitional cell carcinoma (TCC). The tumors were found in women 28-76 years old (mean, 51 years). Fifteen patients presented with stage II, 59 with stage III, and 14 with stage IV disease. Ten neoplasms were composed of only TCC, 48 were predominantly TCC, and 30 had foci of TCC but the predominant component was serous, endometrioid, undifferentiated, or unclassified adenocarcinoma. After the primary resection of the neoplasm, 76 patients received chemotherapy, 4 received chemotherapy and radiotherapy, and 5 received radiotherapy only; 2 refused further treatment and 1 patient died immediately after the first operation. Estimated five-year survival rates were 37% for the entire group and 41% for those who received chemotherapy. Favorable prognostic indicators, statistically significant, were low clinical stage, predominant TCC in the primary tumor, and a negative second-look operation. Other prognostic indicators were the amount of residual tumor after the first operation and tumor differentiation. When the primary neoplasm was predominantly TCC, another prognostic indicator was the type of carcinoma present in the metastases. Five-year follow-up shows that 56% of the patients whose metastases were predominantly TCC have no evidence of disease, whereas only 7% of the patients whose metastases are predominantly non-TCC are disease-free. The authors' study indicates that ovarian carcinomas containing predominant TCC pattern have an excellent response to different chemotherapy regimens. Tumor recurrences and lack of response to chemotherapy are often associated with a change in the histologic appearance of the metastatic lesion.