Endothelial activation and stress index (EASIX) as a predictive biomarker in small cell lung cancer

Endothelial activation and insult may contribute to the aggressive clinical course of small-cell lung cancer (SCLC); however, no predictive biomarker for this pathogenesis has been identified.

To evaluate the clinical impact of the endothelial activation and stress index (EASIX) in SCLC.

In this retrospective study, the EASIX was calculated from measurements of serum lactate dehydrogenase, creatinine, and platelet levels. A total of 264 patients with SCLC treated with platinum-based chemotherapy were stratified into high and low EASIX groups.

Complete and objective response rates in the limited-stage (LD) were 19.5% vs. 33.3% (P= 0.050) and 85.4% vs. 97.9% (P= 0.028) in the high and low EASIX groups, respectively. There was no significant difference in the response rate between the two groups in the extensive-stage (ED). The median overall survival was 9.8 vs. 40.5 months in LD (P< 0.001) and 7.2 vs. 11.9 months in ED (P< 0.001) in the high and low EASIX groups, respectively. In multivariate analyses, a high EASIX level was an independent prognostic factor for worse progression-free and overall survival irrespective of stage.

EASIX may be a potential predictive biomarker of SCLC.