Survival for Metastatic Colorectal Cancer in the Bevacizumab Era: A Population-based Analysis

BackgroundAs of 2006, bevacizumab was available for the treatment of metastatic colorectal cancer (mCRC) in British Columbia (BC). This study compares survival between referred patients diagnosed with mCRC in 2003/2004 (pre-bevacizumab era) and 2006 (bevacizumab era).Patients and MethodsThe BC cancer agency (BCCA) is a cancer network treating approximately 60% of patients with mCRC in BC. For this study, all patients in the BCCA diagnosed with mCRC in 2003/2004 and 2006 were included. The primary objective was to compare overall survival (OS) between the 2 cohorts.ResultsOne thousand four hundred seventeen patients were included: 969 from 2003/2004, and 448 from 2006. Between 2003/2004 and 2006, the proportion of patients treated with systemic therapy for mCRC increased (61.1% to 67.6%; P = .02). The only significant difference in treatment between the cohorts was in the proportion of patients who received bevacizumab (5.9% to 30.6%; P < .001). Median OS significantly differed between the 2 cohorts (13.8 to 17.3 months; P < .001). Median OS for patients who received systemic therapy increased (18.6-23.6 months; P = .001). Median OS for patients who did not receive systemic therapy was unchanged (6.1-5.9 months; P = .65).ConclusionIn this population-based study, median OS for mCRC significantly increased between 2003/2004 and 2006. An increase in the proportion of patients treated with systemic therapy, and the addition of bevacizumab to chemotherapy, seem to have contributed to this improvement in survival.