The efficacy and toxicity of intravenous carboplatin (300 mg/m2) and cycloprosphamide (600 mgs/m2) was evaluated in 44 newly diagnosed patients with advanced stage epithelial ovarian cancer. Cycles were administered at four weekly intervals for a total of 6 cycles, and therapy was provided on an out-patient basis without prehydration or forced diuresis. During treatment patients were assessed by physical, gynaecological and radiological examinations. Forty-four patients with a median age of 54 years (range 28-76) were entered into the study. The majority of patients had serous cystadenocarcinoma, 82% had stage III or IV disease and 87% had grade II or III histologic subtype. Optimal debulking surgery was carried out in only 46% of patients. The overall response rate to carboplatin/cyclophosphamide was 73%, with 55% achieving a clinical complete response. The median survival for all patients was 18+ months (range 2-41+). For those patients who received optimum surgery, median survival was 26+ months, compared with 11+ months for those whose lesion could not be completely resected. Treatment was well tolerated by most patients, with significant nausea and vomiting (WHO grade III-IV) observed in only 11% of 226 cycles of therapy. Myelosuppression was acceptale, with a mean nadir white cell count 4.3 x 10(9)/L (range 1.4-9.0) and a mean nadir platelet count of 273 X 10(9)/L (range 39-536) observed on day 21. There were no therapy-related infective episodes. Significant alopecia developed in 4 patients, but significant nephrotoxicity, ototoxicity or neurotoxicity has not been observed in any patients. This study demonstrates that combination carboplatin/cyclophosphamide is well tolerated in women with advanced stage epithelial ovarian cancer and produces overall response rates and median survival similar to those obtained with cisplatin-containing chemotherapy.