Irinotecan plus cisplatin is no better than paclitaxel plus carboplatin for women with ovarian clear cell carcinoma, according to an international study led by Japanese investigators.
Clear cell carcinoma (CCC) accounts for approximately 10% of epithelial ovarian cancers (EOCs) in Europe and the United States, but is more prevalent in Asia; In Japan CCC accounts for 24% of all EOCs.
In the first phase III, CCC-specific clinical trial, 667 women with stage I to IV CCC were randomized to receive one of two treatment regimens: irinotecan at a dose of 60 mg/m2 on days 1, 8, and 15 plus cisplatin at 60 mg/m2 on day 1 every 4 weeks for six cycles (n = 332) or paclitaxel at a dose of 175 mg/m2 plus carboplatin on day 1 every 3 weeks for six cycles (n = 335).
Japanese women made up 93.5% of the study population, the median age was 53 years, and 6.4% of patients had stage I cancer. Median follow-up time was 44.3 months.
No difference was found between the groups in progression-free or overall survival, Toru Sugiyama, MD, of Iwate Medical University, Morioka, Japan, and associates reported (J Clin Oncol. 2016 July 11. doi: 10.1200/JCO.2016.66.9010).
Both regimens were well tolerated, though the toxicity profiles were different, investigators wrote.
Overall, 72% of patients received all six cycles of their respective chemotherapy treatments. Two-year progression-free survival rates were 73.0% (95% confidence interval, 67.7%-77.5%) among patients receiving irinotecan plus cisplatin, 77.6% (95% CI, 72.4%-81.9%) among patients receiving paclitaxel plus carboplatin, and were not significantly different (HR, 1.17; 95% CI, 0.87-1.58; P = .30).
There was also no significant difference in overall survival between the two treatment arms.
In subgroup analyses, there was no significant difference in progression-free or overall survival by disease stage or tumor size.
Grade 3 or 4 anorexia, diarrhea, nausea, vomiting, and febrile neutropenia were the most common adverse events among women receiving irinotecan plus cisplatin. Grade 3 or 4 leukopenia, neutropenia, thrombocytopenia, peripheral sensory neuropathy, and joint pain were the most common adverse events among women receiving paclitaxel plus carboplatin. No treatment-related deaths occurred in either treatment arm.
This study was funded by the Japanese Gynecologic Oncology Group. Dr. Sugiyama and 18 other investigators had no disclosures to report. Six investigators reported serving in advisory roles for or receiving financial compensation or honoraria from multiple companies.
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