Increasing body mass index during initial immunotherapy improves response rate and survival for patients with advanced non-small cell lung cancer: a retrospective study

Abstract Background/aim: Elevated baseline body mass index (BMI) is independently correlated with the efficacy and prognosis of anti-tumour immunotherapy. But the effects of BMI change in patients undergoing PD-1/PD-L1 monoclonal antibody therapy have not been well studied. Method A retrospective analysis of patients who were consecutively receiving anti-PD-1/PD-L1 inhibitor treatment diagnosed with advanced NSCLC was conducted to investigate the effects of baseline and maximum variation in BMI within the first 12 weeks on objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). Baseline BMI and change in BMI were both analysed as continuous and categorical variables. Results For baseline BMI, only the overweight group showed an improvement in OS ([HR] = 0.67, 95% CI:0.49–0.91, P = 0.011). BMI variation analysis showed significant differences among stable, increase, and decrease groups (P = 0.0033), and the increase group showed a significantly improved OS (HR = 0.38, 95%CI: 0.20–0.74, P = 0.004). Each 1% increase in BMI was associated with a 9% increase in survival time (HR = 0.91, 95%CI:0.87–0.96, P < 0.001). Also, patients in the increased group showed a significantly higher ORR (OR = 5.42, 95%CI:2.02–14.54, P < 0.001). Subsequent analysis revealed that the increase group showed a significant benefit in PFS (HR = 0.57, 95%CI:0.35–0.92, P = 0.022); and each percentage point increase in BMI was associated with a 9% improvement (HR = 0.93, 95%CI:0.89–0.96, P < 0.001). Conclusion Weight gain during treatment should be considered a potentially more potent predictive factor in immunotherapy compared to baseline body mass index (BMI).