Two bi-institutional prospective studies using intraperitoneal oxaliplatin with or without irinotecan during HIPEC following complete cytoreductive surgery for colorectal carcinomatosis.

Abstract

486 Background: In treatment of peritoneal carcinomatosis (PC) of colorectal origin, studies combining cytoreductive surgery (CRS) and hyperthermic intra-peritoneal chemotherapy (HIPEC) have shown encouraging survival results. Intraperitoneal drugs usually used are mitomycin C or oxaliplatin in monotherapy. The aim of this study was to assess long-term survival in patients treated with a new combination of oxaliplatin and irinotecan (ox-irino) and to compare it with that obtained with oxaliplatin alone (ox-alone). Methods: Two bi-institutional prospective studies were carried out. All patients with PC who had undergone CRS with HIPEC using either ox-alone 460 mg/m2 or ox-irino (ox: 300 mg/m2 and irino: 200 mg/m2) from January 1998 to December 2007 were included. Results: 146 patient underwent CRS + HIPEC for PC from colorectal carcinoma. 103 patients received ox-irino and 43 patients received ox-alone HIPEC. The overall mortality rate was 4.1%. The overall morbidity rate was 47.2%. It was significantly lower in the ox-alone group compared to the ox-irino group (34.9% vs. 52.4%, p =0.05). After a median follow-up of 48.5 months, (95%CI 41.0-56.3), the median OS was 41 months (95%CI 32-60) and the median RFS was 15.7 months (95%CI 12-18). The median RFS of the ox-alone group was 16.8 months (95%CI 11-25) and was not significantly different from that of ox-irino group (15.7 months, 95%CI 11-18, p = 0.93). There was no significant difference between the median OS of the ox-alone group (40.83 months, 95%CI 29–61) and the ox-irino group (47 months, 95%CI 32-61, p = 0.94). At 5 years, the OS and the RFS rates were respectively 41.8% (95% CI 25.20-57.58) and 13.8% (95% CI 4.66-27.84) in the ox-alone group and 42.4% (95% CI 28.52-56.09) and 14.2% (95% CI 6.27-25.20) in the ox-irino group. Conclusions: This study confirms the interesting survival results of CRS + HIPEC to treat colorectal PC. 460 mg/m2 of oxaliplatin alone HIPEC is as efficient as 300 mg/m2 of oxaliplatin associated with 200 mg/m2 of irinotecan, but with lower morbidity. Ox-alone HIPEC, should remain the current gold standard. No significant financial relationships to disclose.