To evaluate the efficacy of first-line bevacizumab-based chemotherapy for untreated metastatic colorectal cancer (mCRC) based on age.

Eligibility criteria focused on M1 disease without prior palliative chemotherapy. Choice of chemotherapy regimen was at the physician’s discretion. Predefined efficacy endpoints were response rate, progression-free and overall survival (PFS, OS). Patients were analysed by age (<70 vs. ≥70 years, <75 vs. ≥75 years).

Of 1777 patients, 27% and 12% were ≥70 and ≥75 years, respectively. PFS was shorter in elderly patients (<70 vs. ≥70 years: 10.5 vs. 9.5 months, p = 0.074; <75 vs. ≥75 years: 10.5 vs. 8.9 months, p = 0.00019), as was OS (<70 vs. ≥70 years: 25.8 vs. 22.7 months, p < 0.0008; <75 vs. ≥75 years: 25.8 vs. 20.8 months; p < 0.0001). In the groups <70 and <75 years, PFS was longer in those receiving oxaliplatin-/irinotecan-containing regimens vs. those receiving 5-FU/capecitabine (<70 years: 10.6 vs. 9.0 months; p = 0.0065; <75 years: 10.6 vs. 9.2 months; p = 0.028); no difference in PFS was observed between oxaliplatin-/irinotecan-containing regimens vs. 5-FU/capecitabine regimens in both elderly age-group comparisons (≥70 years: 9.7 vs. 9.2 months; ≥75 years: 8.3 and 9.0 months).