e14168 Background: Immunotherapy has revolutionized the treatment of cancer, however, little is known about the effect of patients’ age on the efficacy of immune checkpoint inhibitors. We did a systematic review and meta-analysis to assess the heterogeneity of immune checkpoint inhibitor efficacy between young and elder patients in pan cancer. Methods: We systematically searched PubMed, Cochrane library, and Embase from January 2000 to November 2018 for randomized controlled trials that had available hazard ratios (HRs) for death according to patients’ age. We also reviewed abstracts and presentations from all major conference proceedings. Retrospective studies and trials that compared anti-PD-1/PD-L1 with other immunotherapies were excluded. The primary outcome was the difference in overall survival (OS). We calculated the pooled overall survival HR and 95% CI in young and elder patients using a random-effects model. Results: A total of 3365 publications were retrieved through initial literature search, 19 randomized controlled trials involving 12276 patients with solid tumors were included for this meta-analysis. PD-1 inhibitors exhibited significantly improved OS over PD-L1 inhibitors in younger patient population (HR 0.67, 95% CI 0.53-0.85), while no differences have been observed in elder population (HR 0.89, 95% CI 0.70-1.13). Subgroup analysis showed that PD-L1 inhibitors plus chemotherapies led to significantly improved overall survival (OS) in elder population (> = 65 years old) over that in younger population (< 65 years old) (HR 1.29, 95% CI 1.01-1.64). However, the opposite tendency was observed with PD-1 inhibitors plus chemotherapies, showing that the younger population obtained better OS benefit compared to the elder population (HR 0.69, 95% CI 0.47-1.01). Conclusions: In general, PD-1 inhibitors exhibited better clinical performance for survival outcome over PD-L1 inhibitors in younger patients. When combined with chemotherapies, PD-1 inhibitors and PD-L1 inhibitors showed distinct efficacy tendency across different age groups, indicating that age should be taken into account when making decisions about treatment strategies. Future studies and explorations of the underlying mechanisms are needed for the further optimization of treatment strategies in clinical practice.
Systematic review and updated network meta-analysis of randomized controlled trials comparing open, laparoscopic-assisted, and robotic distal gastrectomy for early and locally advanced gastric cancer
