Twenty-nine trials (n=3,518 participants) were included in the review: 20 consolidation trials and nine maintenance therapy trials. The average quality score for consolidation trials was 0.68 (range 0.47 to 0.94) and for maintenance trials was 0.70 (range 0.37 to 0.92). Eleven (55%) of consolidation trials and seven (78%) of maintenance trials were reported to be randomised.
Progression-free survival: Continued therapy significantly improved progression-free survival (HR 0.81, 95% CI 0.73 to 0.91; 23 trials). This remained significant for consolidation therapy regimens (HR 0.79, 95% CI 0.68 to 0.93; 16 trials) and maintenance therapy regimens (HR 0.82, 95% CI 0.70 to 0.96; seven trials).
Overall survival: Continued treatment was significantly associated with improved overall survival (HR 0.69, 95% CI 0.58 to 0.81; 26 trials). This remained significant for consolidation regimens (HR 0.68, 95% CI 0.55 to 0.85; 17 trials) and maintenance therapy (HR 0.68, 95% CI 0.51 to 0.90; nine trials).
Toxicity: Neurotoxicity was significantly higher among patients treated with continued therapy (OR 2.25, 95% CI 1.25 to 4.07; six trials). There were no significant differences between continued therapy and control groups for nausea/vomiting (six trials), pain (five trials) and fatigue (four trials).
Results remained significant in sensitivity analyses when only RCTs were included. Other results of the sensitivity analyses were reported. There was evidence of statistical heterogeneity for the overall analysis (p=0.006), analysis of consolidation regimens (p=0.008) and maintenance regimens (p=0.02). Analysis of publication bias found that even if it was present it would not have changed the conclusion of the review. Trim-and-fill analysis suggested that 10 trials may have been suppressed in the literature.