One year maintenance of carboplatin in patients with epithelial ovarian cancer--a phase II study.

Background: The 5 year survival rate in patients with advanced epithelial ovarian cancer is 25-40% and treatment is mainly palliative once the disease recurs.

Objectives: To determine the time to progression, overall survival and toxicity of 1 year maintenance treatment with carboplatin in women with advanced EOC after achieving complete remission with platinum-based combination chemotherapy.

Methods: Twenty-two women with epithelial ovarian cancer stage III-IV previously treated with platinum-based combinations who had achieved complete remission evidenced by symptoms, pelvic examination, computerized tomography and serum CA-125, were assigned to the study protocol consisting of: carboplatin of AUC=6, three cycles every 2 months, followed by two cycles once every 3 months for a total of five courses over 1 year.

Results: Median follow-up in the 22 patients was 83 months (range 18-133 months), median disease-free survival was 36 months (range 2.5-126.4, 95% confidence interval 16.39-56.34). The 5 year survival was 59.7% with a mean overall survival of 83 months (range 18-133, 95% CI 39.11-127.29). Eleven patients have relapsed and died, 11 are alive, 6 are still in complete remission, and 5 are alive with recurrent disease. Grade III-IV toxicity was shown in some of the patients, anemia in 9%, thrombocytopenia in 9%, fatigue in 4.5%, and hypersensitivity in 4.5%.

Conclusions: A 1 year extension of treatment with a single-agent carboplatin, administered to women with advanced EOC who had achieved complete recovery on platinum-based chemotherapy as their first-line therapy, has an acceptable toxicity. The disease-free survival and overall survival values noted in this study are encouraging and warrant further investigation.