This study aimed to define the optimal 'treatment window' for ICI therapy to maximize survival. In this retrospective cohort study, 149 advanced ESCC patients treated with ICIs were analyzed. Progression-free-survival (PFS) and overall-survival (OS) were assessed using Kaplan-Meier methods and Cox models. The median duration of ICI therapy was 21.0 months, with a median follow-up of 34.6 months. Treatment ≥12 months emerged as critical, significantly improving median PFS (14.0 m vs. 9.1, P = 0.006) and median OS (20.5 m vs. 16.8 m, P = 0.022). The survival benefit increased with longer durations (e.g. ≥24 months). For patients with stable disease (SD), maintaining therapy for ≥12 months was crucial, significantly improving OS (19.2 m vs. 15.5 m, P < 0.001), particularly with second-line or later ICI therapy. Subgroup analyses confirmed the robustness of the 12-month threshold, showing significant PFS and OS benefits in patients receiving second-line or later therapy (PFS: 13.4 m vs. 8.6 m, P = 0.031; OS: 20.5 m vs. 16.6 m, P = 0.015) and combination ICI therapy (PFS: 14.1 m vs. 8.3 m, P = 0.004; OS: 20.1 m vs. 16.8 m, P = 0.041). This real-world study identifies a 12-month minimum ICI treatment window for advanced ESCC, with optimal benefit extending to 24 months and beyond, particularly crucial for SD or later-line/combination therapy cases.
Wang et al. (Mon,) studied this question.