CALGB/SWOG 80405 ct DNA Biomarker Evaluation

To investigate treatment-specific mutations that underlie resistance to treatment with chemotherapy +/- bevacizumab or cetuximab in first line metastatic Colorectal Cancer (mCRC) patients, we performed targeted sequencing of circulating free DNA (cfDNA) from longitudinal plasma samples. These samples were collected at baseline (PRE, n=354), during treatment (OTH, n=259), and/or at progression or end of the protocol treatment (EOT, n=355) from CALGB/SWOG 80405, a randomized phase III trial that evaluated the efficacy of chemotherapy plus bevacizumab or cetuximab treatment in first line colorectal cancer patients (NCT00265850).