Adjuvant chemotherapy with irinotecan hydrochloride and cisplatin for clear cell carcinoma of the ovary

Clear cell carcinoma (CCC) of the ovary has distinct characteristics showing resistance to conventional platinum-based regimen. Our aim was to evaluate the effects of combination therapy with irinotecan hydrochloride and cisplatin (CPT-P), comparing to regimen with paclitaxel and platinum (TP). We retrospective reviewed 172 patients with complete surgical staging procedures including lymphadenenctomy. Forty-six patients received CPT-P and 126 patients were treated with TP. Survival of the two groups was compared. Between CPT-P group and TP group, there was no significant difference in median age, performance status, FIGO stage, rate of optimal cytoreduction, and follow-up period. There was no significant difference in progression-free survival of patients with stage I tumors (p=0.95) and suboptimally debulked stage II-IV tumors (p=0.92). Although there was no significant difference of overall survival, progression-free survival of CPT-P group was significantly better than that of TP group in optimally debulked stage II-IV (p=0.03). Multiple regression survival analysis revealed CPT-P regimen (p=0.02) and residual tumor diameter (p<0.01) were both independent prognostic factors in stage II-IV tumors. The combination of CPT-P was shown to have a potential therapeutic benefit for advanced CCC of the ovary, especially for cases with optimal debulking surgery. However, this is a limited retrospective study, therefore we recommend that the CPT-P regimen be evaluated in a larger prospective study.