Risk factors and a prognostic model for patients with borderline resectable locally advanced T3-4N0-1 non-small cell lung cancer: a population-based study

Background: Non-small cell lung cancer (NSCLC) is a malignant disease with a significant morbidity rate. For patients diagnosed with borderline resectable locally advanced (T3-4 invasion and N0-1) NSCLC, the optimal treatment and prognosis are still under debate. This study aimed to develop a predictive nomogram that could assess the prognosis of these patients and optimize clinical decision-making. Methods: Between 2010 to 2015, the survival, demographic and clinical characteristics of patients with borderline resectable locally advanced T3-4N0-1 NSCLC were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Cox proportional hazard regression analyses were conducted to identify potential factors, which were further utilized to develop a dynamic nomogram for personalized prediction. Internal and external validation were conducted to verify the predictive accuracy of the nomogram. Results: Totally, 5,054 eligible records were enrolled into the study cohort. The included patients were divided into a training cohort (n=3,538) and a validation cohort (n=1,516) in a 7:3 ratio. Nine independent prognostic factors (including age, gender, primary site, lymph node removal, differentiation grade, T stage, N stage, histology and adjuvant chemotherapy) were finally included into the nomogram. The developed nomogram exhibited favorable discriminative ability with the C-index =0.71. Moreover, the calibration curves demonstrated excellent agreement between predicted and observed outcomes in both the training and validation cohorts. Notably, subgroup analyses revealed that neoadjuvant chemotherapy was significantly associated with a better overall survival (OS) (P<0.05) in patients staged as T3-4N1. Conclusions: In this study, we developed and validated a prognostic model to assist in clinical decision-making for patients with borderline resectable locally advanced T3-4N0-1 NSCLC. Our findings suggested that patients with T3-4N1 stage disease may derive significant benefits from neoadjuvant chemotherapy.