Abstract Body (Do not enter title and authors here): Background: Metabolic syndrome and obesity are known to increase the incidence of lung cancer. We investigated the association between metabolic health and overweight/obesity phenotypes and clinical outcomes in patients with resectable non-small cell lung cancer (NSCLC).
Methods: This large retrospective cohort study included adult patients who underwent curative upfront surgery for their stage IA-IIIB NSCLC at a tertiary university hospital from January 2010 to December 2020. They were classified into four phenotypes based on the combination of metabolic health status and body mass index categories: metabolically healthy normal weight (MHNW), metabolically unhealthy normal weight (MUNW), metabolically healthy overweight/obesity (MHO), metabolically unhealthy overweight/obesity (MUO). The primary outcomes were disease recurrence and death.
Results: Of the 1,513 patients (342 with MHNW, 585 with MUNW, 122 with MHO, and 464 with MUO), patients with the phenotype of MHO were less likely to experience recurrence (MHO [13.1%] vs. MHNW [16.1%] vs. MUNW [22.9%] vs. MUO [19.2%], p = 0.018) and death (MHO [15.6%] vs. MHNW [24.6%] vs. MHUW [31.3%] vs. MUO [24.8%], p < 0.001) compared to those with other 3 phenotypes. Similar results were observed in Kaplan-Meier curves for the primary outcomes according to the four phenotypes (all log-rank P < 0.05). In multivariate Cox regression analyses, both MHO and MUO phenotypes did not increase the risk of recurrence compared to the MHNW phenotype and were associated with improved survival (MHO: adjusted hazard ratio [HR] 0.60, 95% confidence interval [CI] 0.36-0.98, p = 0.040; MUO: adjusted HR 0.76, 95% CI 0.60-0.96, p = 0.022).
Conclusions: After curative resection for NSCLC, regardless of metabolic health, patients with overweight/obesity were not at an increased risk of recurrence and paradoxically, had favorable overall survival.