Treatment Strategies in Colorectal Cancer Patients With Initially Unresectable Liver-only Metastases

Colorectal cancer patients with initially unresectable liver-only metastases may be cured after downsizing of metastases by neoadjuvant systemic therapy. However, the optimal neoadjuvant induction regimen has not been defined, and no consensus exist on criteria for resectability. In this study colorectal cancer patients with initially unresectable liver-only metastases, as prospectively confirmed by an expert panel according to predefined criteria, will be tested for RAS and BRAF tumor mutation status and selected by location of primary tumor. Patients with RAS or BRAF mutant and/or right sided tumors will be randomised between doublet chemotherapy (FOLFOX or FOLFIRI) plus bevacizumab (schedule 1), and triple chemotherapy (FOLFOXIRI) plus bevacizumab (schedule 2). Patients with RAS AND BRAF wildtype AND left-sided primary tumors will be randomized between doublet chemotherapy (FOLFOX or FOLFIRI) plus either bevacizumab (schedule 1) or panitumumab (schedule 3). Patient imaging will be reviewed for resectability by a central panel, consisting of at least one radiologist and three surgeons every assessment. Central panel review will be performed prior to randomization as well as during treatment, as described in the protocol.