PubMed, Embase and Cochrane Library databases were systematically searched for eligible studies that evaluated the relationship between time to AC and survival outcome. Survival data for HR and 95% CI were extracted and converted to a regression coefficient(β) corresponding to a continuous representation per 4-week delay of AC. Individual adjusted β were combined using a fixed-effects or random-effects model. Heterogeneity was assessed by I2 statistic and publication bias was detected using standard error-based funnel plots.
A total of 11 eligible studies involving 6,017 patients were included in this meta-analysis. Eight studies evaluated the impact of delaying AC on overall survival(OS) and five evaluated the impact of delaying AC on disease-free survival(DFS). The pooled results demonstrated that the initiation of AC per 4-week delay was associated with a significant decrease in OS(HR:1.05, 95% CI: 1.03-1.08, P < 0.001; I2 = 18.5%) and DFS (HR:1.06, 95% CI: 1.02-1.10, P = 0.001; I2 = 40.6%).
The initiation of AC per 4-week delay was associated with worse survival outcomes in GC patients. If physical status and postoperative recovery were appropriated, GC patients should be recommended to receive adjuvant chemotherapy timely.