A UNICANCER phase III trial of hyperthermic intra-peritoneal chemotherapy (HIPEC) for colorectal peritoneal carcinomatosis (PC): PRODIGE 7.

LBA3503 Background: Promising results have been obtained during the last decade using cytoreductive surgery (CRS) plus HIPEC for selected patients with colorectal PC who are amenable to complete macroscopic resection. This is the first trial to evaluate the specific role of HIPEC, after CRS, for the treatment of PC of colorectal origin. Methods: Prodige 7 is a randomized phase III, multicenter trial. Patients with histologically proven and isolated PC, peritoneal cancer index (PCI) ≤25 were eligible. Randomization (1:1) was stratified by center, complete macroscopic resection (R0/1 vs R2), and neoadjuvant systemic chemotherapy. Patients were treated with CRS plus HIPEC with oxaliplatin or CRS alone, in association with systemic chemotherapy. The primary endpoint was the overall survival (OS). Secondary endpoints were relapse-free survival (RFS) and toxicity. 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: 265 patients from 17 centers were included between February 2008 and January 2014: 132 in Arm without HIPEC and 133 in Arm with HIPEC. The median age was 60 years (range: 30-74). Baseline characteristics were well balanced. The overall post-operative mortality rate was 1.5% and was not different between the two arms. The morbidity rates did not differ statistically at 30 days. At 60 days, the grade 3-5 morbidity rate was significantly higher with HIPEC (24.1% vs. 13.6%, p= 0.030). After a median follow up of 63.8 months (95% CI: 58.9-69.8), the median OS was 41.2 months (95% CI 35.1-49.7) in the non-HIPEC Arm and 41.7 months (95% CI: 36.2-52.8) in the HIPEC Arm, HR = 1.00 (95% CI: 0.73-1.37) p = 0.995. The median RFS was 11.1 months (95% CI: 9-12.7) in non-HIPEC Arm and 13.1 months (95% CI: 12.1-15.7) in HIPEC Arm, 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. Conclusions: The therapeutic curative management of PC from colorectal cancer by CRS shows satisfactory survival results. While the addition of HIPEC with oxaliplatin does not influence the OS. Clinical trial information: NCT00769405.