Retrospective analysis of the impact of dose delay and reduction on outcomes of colorectal cancer patients treated with FOLFIRIâbased treatment

Objectives To determine the relationship between chemotherapy dose delay/reduction with progression-free survival (PFS) and overall survival (OS) in colorectal cancer patients treated with FOLFIRI based first-line chemotherapy in real-world retrospectively study. Methods We identified 144 eligible patients with advanced CRC who received FOLFIRI as first-line based treatment. The study protocol was submitted to the institutional review board and was exempted. Dose delay was defined as an average delay of more than 3 days (>3 days vs. [less than or equal to]3 days) from the intended date. Dose reduction (actual dose/standard dose * 100%) [less than or equal to]85% was considered as chemotherapy reduction in the chemotherapy dose relative to the standard (mg/m.sup.2 ) regimen for all cycles. Relative dose intensity (RDI) [less than or equal to]80% was described as chemotherapy reduction. OS and PFS were measured using Kaplan-Meier and Cox proportional hazard models. Results There were 114 patients with chemotherapy dose delay (dose delay >3 days). PFS of patients without dose delay had better survival than patients with dose delay (p = 0.002). There were 28.47% patients treated with dose reduction of 5-Fu. PFS and OS were better in patients without 5-Fu dose reduction than in patients with 5-Fu dose reduction with p values of 0.024 and