Impact of body mass index on progression-free survival and endocrine immune-related adverse events in advanced NSCLC patients treated with nivolumab: A retrospective cohort study.

OBJECTIVE

Body mass index (BMI) is a well-established prognostic factor in many cancer types. While BMI has been paradoxically associated with improved outcomes under immune checkpoint inhibitors (ICIs), its role in toxicity risk remains underexplored. This study examines the relationship between BMI and both progression-free survival (PFS) and immune-related adverse events (irAEs) in patients with advanced non-small cell lung cancer (NSCLC) receiving second-line treatment with nivolumab.

METHODS

This retrospective study examined 305 patients with histologically confirmed stage IV NSCLC who experienced progression after platinum-based chemotherapy. Patients were grouped based on whether their BMI was above or below the median value of 24.8 kg/m2. PFS was assessed using Kaplan-Meier analysis. Frequencies of endocrine, hematologic, gastrointestinal, hepatic, and pulmonary toxicities were compared between BMI groups. Statistical significance was set at p<0.05.

RESULTS

No statistically significant difference in PFS was observed between BMI groups (<24.8: 7.53 months vs. ≥24.8: 8.30 months, p>0.05). Endocrine irAEs, however, occurred more frequently in patients with a higher BMI (p=0.034). No significant associations were found between BMI and hematologic (p=0.637), hepatic, gastrointestinal, or pulmonary irAEs. BMI was not predictive of PFS but was associated with endocrine toxicity.

CONCLUSION

These findings suggest that BMI may serve as a simple indicator for toxicity risk stratification in immunotherapy settings.