Surgical resection of liver metastases and survival outcomes in real-life for metastatic colorectal cancer (mCRC) patients treated in front-line with cetuximab (CTX): The EREBUS cohort.

Abstract

e14514 Background: CTX has demonstrated improved survival outcomes and resection rate in unresectable mCRC patients (pts) but little data is available from real-life use. Methods: EREBUS is a French multicentre (n=65) cohort that included pts with unresectable mCRC and wt KRAS initiating 1st-line CTX in 2009 and 2010, and followed 12 months. An expert committee validated baseline resectability and resection results. Resection rates and survival outcomes were described according to metastases site: liver-only, liver-not exclusively, other. Results: 389 pts were included: 37.8% liver-only metastases, 38.3% liver-not exclusively, 23.9% other. Baseline characteristics of the cohort: median age 64 yrs, 67.4% male, 77.9% ECOG=0-1, 55.5% primary tumor resection, 53% single metastatic site. Combined chemotherapy regimen were with irinotecan (56.6%) or oxaliplatin (38.2%). Median duration of CTX use was 4.8 months. 97 pts (24.9%, 95%CI: 20.6-29.2) had metastases resection; rates for liver-only: 36.7% (28.9-44.5), liver-not exclusively: 20.8% (14.3-27.3), other: 12.9% (6.9-21.5). Among them, 51.5% had radical resection with R0+/-radiofrequency (liver-only: 61.1% and liver-not exclusively: 32.3%), 11.3% R1+/-radiofrequency (liver-only: 16.7% and liver-not exclusively: 3.2%) and 9.4% missing metastases, 27.3%R2. 52.6% had post-operative complications (20.6% infection, 8.2% thromboembolic event, 8.2% other cardiovascular event, 3.1% death). Median PFS for the cohort was 9.7 months (8.6-10.5). In multivariate Cox analysis progression was independently associated with metastases site, liver-only: HR=1.93 (1.36-2.74), liver-not exclusively: HR=1.46 (1.06-2.02). The 1-yr OS probability was 71.3% (66.4-75.6) without any site difference. In Cox analysis, death was less likely in responders with or without metastases surgery: HR=0.26 (0.08-0.90) and HR=0.37 (0.21-0.63). Conclusions: This cohort shows that 1st-line CTX in wt KRAS mCRC allows a high proportion of metastases resection, particularly in liver-only. It also provides data on rarely studied mCRC pts (liver-not exclusively and other metastases).