Observational Cohort Study of Patients With Metastatic Colorectal Cancer Initiating Chemotherapy in Combination With Bevacizumab (CONCERT)

Abstract

Background: The CONCERT study (observational cohort study of patients with metastatic colorectal cancer initiating chemotherapy in combination with bevacizumab) aimed to describe patient characteristics, bevacizumab use, its efficacy in terms of progression-free survival (PFS) and overall survival (OS), and its safety in patients with metastatic colorectal cancer (mCRC) treated in daily medical practice.

Patients and methods: CONCERT was an observational, prospective, multicenter, cohort study conducted in France. Patients with mCRC initiating bevacizumab combined with chemotherapy were included and followed up for ≤ 36 months.

Results: Overall, 737 evaluable patients were assessed, and 71%, 21%, and 8% initiated bevacizumab as first-, second-, or third-line therapy or more, respectively. Their mean age was 64.5 years (range, 25-88 years), and 60% were men. Bevacizumab was mainly started at 5 mg/kg every 2 weeks (95%) and mostly combined with FOLFIRI (leucovorin, 5-fluorouracil, irinotecan; 68.0%) or FOLFOX (leucovorin, 5-fluorouracil, oxaliplatin; 22.0%). The median PFS was 10.4 months (95% confidence interval [CI], 9.6-11.3) in first-line, 8.5 months (95% CI, 7.0-9.2) in second-line, and 6.3 months (95% CI, 4.5-8.9) in third-line or beyond. The corresponding median OS was 25.3 months (95% CI, 21.5-28.6), 19.1 months (95% CI, 15.7-22.6), and 14.9 months (95% CI, 11.6-20.4). In first-line treatment, primary tumor resection and oxaliplatin-based chemotherapy were prognostic of a longer PFS. Eastern Cooperative Oncology Group performance status ≥ 2, > 1 metastatic sites, and intermediate or high risk using the Köhne prognostic index were associated with shorter PFS. The safety profile of bevacizumab combined with chemotherapy was comparable to that found by other observational studies of mCRC.

Conclusion: The efficacy and safety results of bevacizumab plus chemotherapy as first- and second-line treatment of mCRC in daily practice in the CONCERT observational, prospective study were in line with those from randomized clinical studies.

Keywords: All lines of treatment; Bevacizumab use; OS; PFS; Prognostic factors.