Comorbiditeit COPD geeft korte termijn overlevingsvoordeel maar langetermijnrisico bij uitgestrekte stadium longkanker

BACKGROUND: Currently, predictive biomarkers and clinical outcomes remain undefined for patients suffering from small-cell lung cancer (SCLC) with concurrent chronic obstructive pulmonary disease (COPD). This study sought to evaluate how pre-existing COPD influences SCLC patients receiving immunotherapy, while exploring potential lung function and serological markers to identify which COPD patients are most likely to respond favorably to immune-based treatments. METHODS: This retrospective analysis included individuals with pathologically confirmed extensive-stage SCLC (ES-SCLC) treated with initial chemoimmunotherapy at Jinling Hospital. All participants underwent baseline pulmonary function testing. We collected clinical characteristics (age, sex, and therapeutic regimens), lung function metrics [vital capacity (VC), percentage of predicted VC (VC%), forced expiratory volume in 1 second (FEV1), FEV1/forced VC (FVC) ratio, and percentage of predicted peak expiratory flow (PEF%)], alongside hematological indices (albumin, lactate dehydrogenase, and counts of lymphocytes, monocytes, eosinophils, and neutrophils). Overall survival (OS) served as the primary endpoint. To pinpoint survival predictors, we utilized stepwise multivariate Cox proportional hazards models, log-rank testing, and landmark analyses. RESULTS: The cohort comprised 100 ES-SCLC patients evaluated over a median follow-up of 19 months (range, 13.9-27.7 months). Among them, 59 individuals had comorbid COPD, predominantly categorized as Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages 1-2 (n=46, 78.0%), with the remainder in stages 3-4 (n=13, 22.0%). Landmark analysis revealed a dual survival pattern: prior to 9 months, the COPD group demonstrated significantly better OS versus non-COPD patients (P=0.04); conversely, beyond the 9-month mark, their OS became significantly worse (P=0.01). Progression-free survival (PFS) did not differ meaningfully between the two cohorts (P=0.76). Multivariate modeling highlighted three potential prognostic indicators: maximum VC% (VCMAX%) >68.8% [hazard ratio (HR) =0.23, 95% confidence interval (CI): 0.08-0.72; P=0.01], absolute neutrophil count >3.80×109/L (HR = 0.20, 95% CI: 0.07-0.59; P=0.004), and PEF% >65% (HR = 0.37, 95% CI: 0.10-1.34; P=0.13). CONCLUSIONS: In the context of ES-SCLC chemoimmunotherapy, coexisting COPD appears to offer short-term survival advantages but poses a long-term mortality risk. For these dual-diagnosis patients, elevated baseline neutrophils and a higher VCMAX% are strongly associated with improved clinical outcomes. These indicators could serve as valuable tools for stratifying COPD patients to optimize immunotherapeutic strategies in SCLC.