Predictive factors of survival in patients with advanced colorectal cancer: an individual data analysis of 602 patients included in irinotecan phase III trials

Background: The infusional LV5FU2 and Arbeitsgemeinschaft Internische Onkologie (AIO) regimens are used widely in the treatment of advanced colorectal cancer. Irinotecan combined with these regimens increases survival in front-line treatment. Irinotecan also improves survival in second-line treatment. Patients and methods: Univariate and multivariate analyses based on the individual data of 602 patients included in two phase III trials were performed to determine predictive factors of survival in advanced colorectal cancer. Results: Three factors were independently associated with a better progression-free survival: weight loss <5% [hazard ratio (HR) 1.25; 95% confidence interval (CI) 1.00-1.58], World Health Organization performance status (WHO PS) 0-1 (HR 1.29; 95% Cl 1.08-1.54) and irinotecan (CPT-11)-containing regimens (HR 1.48; 95% Cl 1.03-2.13). Five factors were independently associated with a better overall survival: weight loss <5% (HR 1.67; 95% Cl 1.29-2.14), WHO PS 0-1 (HR 1.88; 95% CI 1.27-2.75), one or two metastatic sites (HR 1.24; 95% Cl 1.01-1.53), alkaline phosphatase values not over twice the normal range (HR 1.71; 95% Cl 1.30-2.24) and CPT-11-containing regimens (HR 1.31; 95% Cl 1.07-1.61). Conclusions: The present analysis confirms that CPT-11-based chemotherapy regimens are independently associated with a better survival in patients with advanced colorectal cancer. Age was not identified as a prognostic factor in this analysis.