Quenet F, et al. - Researchers conducted the first trial assessing the specific role of hyperthermic intra-peritoneal chemotherapy (HIPEC) after cytoreductive surgery (CRS) for the treatment of peritoneal carcinomatosis (PC) of colorectal origin. They obtained satisfactory survival results with the therapeutic curative management of PC from colorectal cancer by CRS. No influence on OS was noted with the addition of HIPEC with oxaliplatin.

Methods

• For Prodige 7 (a randomized phase 3, multicenter trial), patients were eligible if they had histologically proven and isolated PC and peritoneal cancer index (PCI) ≤25.
• Researchers performed stratification of randomization (1:1) by center, complete macroscopic resection (R0/1 vs R2), and neoadjuvant systemic chemotherapy.
• Treatment included CRS plus HIPEC with oxaliplatin or CRS alone, along with systemic chemotherapy.
• The overall survival (OS) was assessed as the primary endpoint, and relapse-free survival (RFS) and toxicity as secondary endpoints.
• They determined that 264 patients were required to show a gain in median OS from 30 to 48 months (HR = 0.625) with a two-sided α = 0,046 and 80% power.

Results

• From February 2008 to January 2014, 265 patients (median age was 60 years [range: 30-74]) from 17 centers were included: 132 in Arm without HIPEC and 133 in Arm with HIPEC.
• The groups were well balanced regarding baseline characteristics.
• The two arms showed no differences in terms of overall post-operative mortality rate (1.5%).
• At 30 days, no statistical differences regarding morbidity rates were observed.
• The grade 3-5 morbidity rate was significantly higher with HIPEC (24.1% vs 13.6%, p=0.030) at 60 days.
• After a median follow up of 63.8 months (95% CI: 58.9-69.8), the non-HIPEC Arm showed the median OS of 41.2 months (95% CI 35.1-49.7) and the HIPEC Arm showed the median OS of 41.7 months (95% CI: 36.2-52.8), HR = 1.00 (95% CI: 0.73-1.37) p=0.995.
• The median RFS was 11.1 months (95% CI: 9-12.7) and 13.1 months (95% CI: 12.1-15.7) in non-HIPEC Arm and HIPEC Arm, respectively, HR = 0.90 (95% CI: 0.69-1.90) (p=0.486), whilst the 1-year RFS rates were 46.1% in non-HIPEC Arm and 59 % in the HIPEC Arm.