Abstract
OBJECTIVE: This retrospective cohort study aims to describe the treatment patterns and evaluate survival outcomes in patients aged 70 years or older with metastatic non-small cell lung cancer (mNSCLC), and to identify independent prognostic factors for overall survival (OS). METHODS: We retrospectively reviewed medical records of 298 patients aged ≥70 years with mNSCLC diagnosed between June 2021 and December 2024. Patients were categorized into an active anti-tumor therapy (ATT) group and a best supportive care (BSC) group for descriptive purposes. Key clinical data, including molecular biomarker status (EGFR, ALK, PD-L1) and Geriatric Nutritional Risk Index (GNRI), were collected for a subset of patients. A multivariate Cox proportional-hazards model was used to identify independent prognostic factors for OS across the entire cohort. RESULTS: Of the 298 patients, 93 (31.2%) received ATT and 205 (68.8%) received BSC. The decision for ATT was significantly associated with better baseline ECOG performance status (ECOG-PS) and fewer comorbidities, indicating profound selection bias. The median OS was 18.0 months in the ATT group and 6.0 months in the BSC group. This difference is descriptive and cannot be interpreted as a treatment effect due to the baseline imbalances. Within the ATT group, treatment modalities included chemotherapy (n = 54), targeted therapy (n = 11), and combination therapy (n = 28). In the multivariate analysis of the entire cohort, better ECOG PS (0–1 vs. 4: HR = 0.28, P < 0.01), fewer comorbidities (0 vs. ≥3: HR = 0.17, P < 0.001), higher GNRI (≥ 98 vs. <92: HR = 0.55, P = 0.02), and adenocarcinoma histology (vs. non-adenocarcinoma: HR = 0.68, P = 0.04) were independent predictors of longer OS. CONCLUSION: In this real-world cohort of elderly mNSCLC patients, treatment selection was heavily influenced by baseline health status. Independent prognostic factors for longer survival were better performance status, lower comorbidity burden, better nutritional status (higher GNRI), and adenocarcinoma histology. These findings underscore the importance of comprehensive geriatric and nutritional assessment in this population and highlight the need for prospective trials to guide treatment decisions.