Genomic alterations to predict response to irinotecan-based chemotherapy in metastatic colorectal cancer.

586 Background: No evidence exists concerning the superiority of oxaliplatin versus irinotecan-based chemotherapy for metastatic colorectal cancer. The choice is currently made by the clinicians according to awaited toxicity and association with targeted therapy. The correlation between response to chemotherapy (oxaliplatin and irinotecan containing regimens) and genomic alterations was investigated in metastatic colorectal cancer patients included in the ProfiLER protocol (NCT 02029001). Methods: From 03/2013 to 03/2014, 62 patients with metastatic colorectal cancer were included in the ProfiLER trial. Tumor samples were analyzed for mutations/insertions/deletions and copy number variations using target high-throughput sequencing (NGS) and comparative genomic hybridization array (CGH). Clinical data were collected retrospectively. We defined irinotecan and/or oxaliplatin responders as patients having CR, PR, SD as best response and non-responders as those having PD as best response. Results: 50/62 tumor ...