A biomarker analysis of plasma RIME and PD-L1 for stratifying first-line immunochemotherapy outcomes in advanced ESCC

Clinical benefit from first-line PD-1 inhibitor plus chemotherapy in advanced ESCC remains heterogeneous, and PD-L1 alone provides limited stratification. We evaluated plasma lncRNA RIME as a potential biomarker for stratifying first-line treatment outcomes in a multicenter cohort of patients with advanced ESCC. In the chemotherapy plus PD-1 inhibitor group, RIME-low was associated with higher ORR and better PFS/OS, whereas RIME-high was associated with poorer outcomes. Joint RIME/PD-L1 assessment further distinguished clinical benefit. Nested-model analyses showed that RIME provided non-redundant outcome information beyond PD-L1, and treatment-by-RIME interactions supported an exploratory predictive signal for ORR and PFS. Overall, plasma RIME was associated with outcome stratification and represents a potential predictive biomarker for immunochemotherapy benefit in ESCC.