Effect of longitudinal changes of cachexia on the efficacy and toxicity of immune checkpoint inhibitors in esophageal squamous cell cancer (ESCC) patients.

PURPOSE: Immune checkpoint inhibitors (ICIs) have enhanced survival in advanced esophageal squamous cell cancer (ESCC) patients, but their efficacy varies. Cachexia, characterized by muscle loss and significant weight loss, might influence ICI response. This study examines the relationship between cachexia's longitudinal changes and ICI outcomes in ESCC patients.

METHODS: ESCC patients undergoing at least two ICI cycles from 2017 to 2021 were studied. Cachexia's baseline and evolving patterns during ICI treatment were observed. Kaplan-Meier and Cox regression analyses were used to assess cachexia's effect on ICI efficacy. Chi-square tests were used to determine cachexia's link to immune-related adverse effects (irAEs).

RESULTS: Two hundred seventy-eight ICI-treated patients had a median progression-free survival (PFS) of 5.78 months and overall survival (OS) of 8.3 months. Pretreatment cachexia led to worse outcomes: PFS 7.87 versus 5.3 months, time to progression (TTP) 10.9 versus 6.1 months, and OS 14.3 versus 9.2 months. Irreversible cachexia showed the poorest results. Cachexia's changes weren't associated with irAEs.

CONCLUSION: Baseline and evolving cachexia significantly impact ICI efficacy in ESCC patients. Continuous cachexia monitoring during ICI therapy is crucial for optimal ESCC management.