Impact of cachexia on the efficacy of first-line immunotherapy in extensive-stage small-cell lung cancer patients.

Abstract

e20620 Background: This study was to investigate the association between cachexia and prognosis in extensive-stage small-cell lung cancer(ES-SCLC) patients who received first-line immunotherapy. And the prognostic values of some systematic inflammatory and nutritional indexes were also evaluated. Methods: Data of 123 ES-SCLC patients receiving immunotherapy as first-line treatment in one single center from June 2019 to February 2021 were analyzed. Development of cachexia after the initiation of immunotherapy was defined as patients with more than 5% weight loss over past 6 months, or more than 2% weight loss with body mass index (BMI) less than 20 kg/m2. Endpoints included response rate, progression-free survival (PFS) and overall survival (OS). Univariate and multivariate survival analysis were performed to identify the factors correlated with PFS and OS. Results: At evaluation after 6 months of initial treatment, cachexia was presented in 51 patients(41.5%). The treatment response and survival of patients with cachexia were worse than those without. The overall median overall survival (OS) was 14.4 months (95% CI 13.3–15.6). The overall median progression-free survival (PFS) was 8.1 months (95% CI 7.0–9.2). The median PFS was significantly longer in patients without bone metastases at diagnosis(HR = 2.362,95%CI:1.452-3.842;p = 0.001), without cachexia(HR = 1.802,95% CI: 1.121-2.895; p = 0.015), and with lower change of total protein(HR = 1.799,95% CI: 1.084–2.984; p = 0.023). The median OS was significantly shorter in patients with poor ECOG PS (HR = 1.904, 95% CI: 1.017-3.564; p = 0.044), higher baseline SII (HR = 2.135,95% CI: 1.117–4.080; p = 0.022), with cachexia(HR = 2.020,95% CI: 1.075-3.795; p = 0.029), advance M stage(HR = 3.111,95% CI:1.545–6.262; p = 0.001) and higher post-treatment SIRI (HR = 2.135,95% CI: 1.281–4.697; p = 0.007). Conclusions: ES-SCLC patients who develop cachexia after first-line immunotherapy have a poor prognosis. our study also confirms that baseline SII and SIRI at 6 weeks after treatment appears to be promising predictors for OS of ES-SCLC who treated with first-line immunotherapy.