Aims: Bevacizumab plus chemotherapy (CT) has been the standard treatment for advanced colorectal cancer (ACRC) in the last decade. However, whether geriatric patients treated with this combination achieved more benefits or suffered severer toxicities than CT alone remained controversial. This meta-analysis was aimed to provide more convincing evidence.
Subjects and methods: Randomized control trials (RCTs) and retrospective comparative studies on the comparison between bevacizumab plus CT and CT for geriatric ACRC patients were retrieved in PubMed, Web of Science, EMBASE, and Ovid until June 2016. One RCT, five subgroup analyses of RCTs, and two retrospective studies with efficacy and safety data were identified, involving a total of 2813 cases. The included primary outcomes were overall survival (OS), progression-free survival (PFS), and adverse events (AEs).
Results: For geriatric ACRC, both OS (hazard ratio [HR] 0.83, 95% confidence interval [CI] 0.74-0.94, P = 0.003) and PFS (HR 0.55, 95% CI 0.48-0.63, P < 0.001) have been improved after the addition of bevacizumab to CT. The odds ratios (ORs) for total grade and grade 3-5 AEs were 1.85 (95% CI 1.12-3.04, P = 0.02) and 2.09 (95% CI 1.69-2.58, P < 0.001), respectively. For overall grade toxicities, proteinuria (OR 10.89, 95% CI 1.37-86.28, P = 0.02), hypertension (OR 4.44, 95% CI 1.85-10.62, P < 0.05), and fistulae/abscess (OR 12.07, 95% CI 1.54-94.88, P < 0.05) were significantly higher in the bevacizumab arm. For grades 3-5, increased risk of hypertension (OR 3.91, 95% CI 2.48-6.16, P < 0.001), arterial thromboembolism (OR 3.25, 95% CI 1.70-6.19, P < 0.001), and venous thromboembolism (OR 2.17, 95% CI 1.11-4.25, P = 0.02) was observed in the bevacizumab group.
Conclusions: After the addition of bevacizumab to CT in geriatric ACRC, both PFS and OS could be significantly improved, while it would also lead to some high-grade AEs, hypertension, and arterial and venous thromboembolism.