Clinical outcomes of intensive versus less intensive first-line chemotherapy for metastatic colorectal cancer.

Aims: Physicians determine the treatment regimen for metastatic colorectal cancer on a case-by-case bases, according to the individual disease characteristics. We retrospectively compared the baseline characteristics and efficacies of first-line treatment among patients with metastatic colorectal cancer who received intensive therapy involving fluoropyrimidine plus oxaliplatin and/or irinotecan, potentially with molecularly targeted agents as well, versus less intensive fluoropyrimidine and/or bevacizumab therapy. Materials & methods: Data were collected from a medical claims database. The efficacy outcomes were: time to treatment failure, time to first subsequent therapy and overall survival. Results: The less intensive therapy group (n = 633) had higher median age, lower daily activity levels and shorter time to treatment failure, time to first subsequent therapy and overall survival than the intensive therapy group (n = 3829). Combination therapy with molecularly targeted agents and bevacizumab improved treatment efficacy outcomes in the intensive and less intensive groups, respectively. Conclusion: Patient age and daily activity levels were important factors for determining treatment intensity.