Effectiveness of first- or second-line bevacizumab (BV) treatment (tx) in elderly patients (pts) with metastatic colorectal cancer (mCRC) in ARIES, an observational cohort study (OCS).

Abstract

3625 Background: BV (Avastin) + chemotherapy (CT) prolongs survival for 1st- or 2nd-line tx of mCRC. Prior trials for BV included low proportions of elderly pts, for whom there is little information about effectiveness of BV tx, particularly in 2nd-line. Methods: We assessed progression-free (PFS) and overall survival (OS) for pts <70 and ≥70 yrs receiving 1stor 2nd-line BV + CT in the ARIES OCS, using Kaplan-Meier methods. A Cox proportional hazards regression model was also used with multivariate adjustment for baseline factors: sex, race, ECOG PS, albumin, alkaline phosphatase, hypertension, diabetes mellitus, site of and surgical resection of 1o tumor, prior adjuvant tx. Results: As of 9/20/10, 1550 1st-line and 482 2nd-line pts from 248 US sites have enrolled. BL characteristics, OS and PFS for pts < or ≥70 yrs are shown in the table. Survival characteristics were similar among men and women. The incidences of BV-targeted adverse events were similar for pts <70 and ≥70 yrs within 1st and 2nd-line cohorts. Conclusions: This is the first study to describe effects of 2nd-line BV tx for mCRC in a large population of elderly pts. Within the 2nd-line cohort there were no significant differences between median OS and PFS in pts <70 and ≥70 yrs. Within the 1st-line cohort, median OS in pts ≥70 yrs was significantly lower than in pts <70 yrs. First-line Second-line <70 yrs (n=1,126) ≥70 yrs(n=424) <70 yrs(n=336) ≥70 yrs(n=146) Median age (range) 58.0 (18-69) 75.0 (70-92) 58.0 (24-69) 76.0 (70-96) Sex, male, % 56.7 57.3 54.8 61.0 Race, % White Black Other . 79.3 13.6 7.1 . 84.4 10.8 4.8 . 82.1 11.6 6.3 . 83.6 8.9 7.5 Median follow-up (range) 22.2 (1.1-48.2) 18.7 (0.3-48.1) 17.2 (1.2-45.5) 15.8 (0.6-45.5) Survival characteristics (95% CI) Median PFS 10.3 (9.8-10.9) 9.9 (8.9-10.4) 7.9 (7.2-8.3) 7.9 (6.7-9.2) Hazard ratio (HR) Univariate Multivariate* . 1 (reference) 1 . 1.11 (0.99-1.25) 1.11 (0.98-1.25) . 1 1 . 0.94 (0.77-1.15) 0.96 (0.78-1.19) Median OS 25.1 (23.1-26.9) 19.6 (18.1-21.6) 18.7 (17.0-21.4) 17.0 (13.4-21.8) HR Univariate Multivariate* . 1 1 . 1.29 (1.13-1.48) 1.23 (1.06-1.42) . 1 1 . 1.10 (0.88-1.37) 1.17 (0.93-1.48) * Covariates are described in methods section.