Effectiveness of FIr-B/FOx and liver metastasectomies in liver-only metastatic colorectal cancer (MCRC).

Abstract

582 Background: Effectiveness of liver metastasectomies was evaluated in liver-MCRC patients treated with FIr-B/FOx association in a previous phase II study (Bruera et al, submitted 2010). Methods: Treatment schedule: 12h-timed-flat-infusion/5-Fluorouracil 900 mg/m2 days 1-2, 8-9, 15-16, 22-23; Irinotecan 160 mg/m2, Bevacizumab 5 mg/kg days 1, 15; Oxaliplatin 80 mg/m2 days 8, 22; every 4 weeks. Resection rate, activity, efficacy were analysed and compared in liver-only versus multiple metastatic sites and single versus multiple liver metastases. Results: Liver-MCRC were 33: liver-only 22 patients (67%); multiple metastatic sites 11 patients (33%). Liver metastasectomies were performed in 13 patients (11 R0, 84.6%): 26% of 50 MCRC patients enrolled in the FIr-B/FOx phase II study; 39% of liver-MCRC patients; 54% of liver-only, 6 of 9 (67%) single and 6 of 13 (46%) multiple liver metastases; one liver and lung metastasectomy. Pathologic complete responses (CRs) were 2 (15%); downsizing with modification of surgical resectability, 9 patients (41%); conversion rate of unresectable liver metastases, 83%. Overall activity, including 3 clinical CR, in liver-only patients, 68%. ORR, PFS, OS, respectively: in liver-MCRC patients, 84%, 11 and 23 months; in liver-only metastases, 86%, 17 and 44 months; in liver metastasectomies, 100%, 21 months (PFS from liver surgery 10 months) and 47 months. Significantly increased efficacy: PFS and OS in liver-only versus multiple metastatic sites (p 0.006 and 0.011, respectively) and single versus multiple liver metastasis (p 0.026 and 0.022, respectively). Conclusions: FIr-B/FOx chemotherapy increases resection rate of liver metastases, thus significantly improving efficacy of liver-only MCRC patients. No significant financial relationships to disclose.