Abstract
Four-drug regimens, such as FIr-B/FOx schedule, can improve efficacy of first-line treatment of metastatic colorectal cancer (MCRC) patients. The present study specifically evaluates feasibility of FIr-B/FOx first-line intensive regimen in fit young-elderly MCRC patients, representing approximately 40% of overall MCRC patients. Activity, efficacy, and safety were equivalent to overall MCRC patients, not significantly different according to KRAS genotype. Clinical outcome was significantly prolonged in liver-limited compared to other/multiple metastatic disease. Safety evaluation of the individual young-elderly patient showed that limiting toxicity syndromes (LTS) in multiple sites were significantly increased, compared to LTS in single site, with respect to non-elderly patients.