Progression-free survival as a surrogate for overall survival in gastro-esophageal cancer trials with immunotherapy: A meta-analysis

While the correlation between treatment effects on PFS and OS was weak in ESCC, it was moderate in PD-L1-low GEA, and good in PD-L1-high GEA. Therefore, PFS is an adequate co-primary endpoint in future trials investigating novel ICIs-based regimens in GEA, especially if the analyses are pre-planned in PD-L1-high subgroups.