Efficacy and safety of irinotecan-based chemotherapy for advanced colorectal cancer outside clinical trials: an observational study.

Background: This prospective observational study in typical community-based outpatient clinics evaluated the efficacy and toxicity of weekly and biweekly irinotecan-based chemotherapies and their compatibility depending on age. Methods: 601 patients with advanced or metastatic colorectal cancer receiving first-, second-, or third-line irinotecanbased therapy were regularly analyzed for response and toxicity until the end of therapy. Results: The median age was 65 (28–87) years, approximately one-third of the patients were ≥70 years old. Of all patients, 405 were treated weekly and 68 biweekly. Median overall survival (OS) for first-line therapy was 26.5 months for the <70-year-old patients …