Meta-analysis comparing maintenance strategies with continuous therapy and complete chemotherapy-free interval strategies in the treatment of metastatic colorectal cancer

There is as yet no consensus as to the best choice among the three treatment options (maintenance, complete chemotherapy-free intervals [CFIs], and continuous) for metastatic colorectal cancer (CRC). We performed a meta-analysis of six trials (N = 2, 454 patients) to compare the safety and efficacy of those three treatment strategies. Maintenance appeared to offer an advantage over CFI with respect to progression-free survival (PFS) (hazard ratio [HR]: 0.53, 95% confidence interval [CI], 0.40–0.69). PFS and overall survival (OS) were comparable between the maintenance and continuous strategies (HR: 1.18, 95% CI, 0.96–1.46; HR: 1.05, 95% CI, 0.98–1.27, respectively), as was OS between the maintenance and CFI strategies (HR: 0.84; 95% CI, 0.70–1.00). The incidence of grade 3/4 toxicity, including neutropenia, neuropathy, hand-foot syndrome and fatigue, was lower with maintenance than with continuous therapy. A maintenance regimen utilizing bevacizumab-based doublets appeared to confer a slight advantage over bevacizumab monotherapy with respect to PFS (P = 0.011). Maintenance appeared to reduce cumulative grade 3/4 toxicity as compared to the continuous strategy, while showing comparable efficacy. Bevacizumab-based doublets appeared to be of particular value in patients with metastatic CRC.