A retrospective review of nutritional status and immunotherapy in lung cancer.

Abstract

e14112 Background: Immunotherapy has transformed cancer treatment, including lung cancer. Approximately 20-25% of patients respond, therefore making it pivotal in understanding what factors may effect outcomes. There have been previous reports of obesity associated with an increased efficacy of PD-1/PD-L1 blockade and cachectic patients not responding as well. In this study, we aim to assess the association of body mass index (BMI) with outcomes of lung cancer patients being treated with immunotherapy. Methods: An IRB approved retrospective review of lung cancer patients receiving immunotherapy between 2014 and 2017 at the Monter Cancer Center, Northwell Health was conducted. Patients were categorized in underweight (BMI < 18.5), normal weight (BMI of 18.5 to < 25), overweight (BMI 25 to 30) or obese (BMI > 30) arms. The groups were compared using the log-rank test. Kaplan-Meier was used for overall survival (OS) and progression free survival (PFS) and Cox regression models were used to adjust for potential confounders. Results: A total of 116 were included in the analysis, with a median age of 70 (95% CI, 62.5 to 75.5). Ten (8.6%) were underweight, 44 (37.9%) were normal weight, 32 (27.6%) were overweight, and 30 (25.9%) were obese. BMI classification were not found to be a significant predictor of survival, after adjusting for therapy duration (p = 0.44). PFS was 6.6, 6.0, and 6.9 months for patients in the underweight, normal weight, and overweight/obese groups, respectively. Of 116 subjects, 46 (40%) died within the follow up period: 3 (30%), 17 (39%), 11 (34%), and 15 (50%) respectively. Additional post hoc analysis showed that patients with low nutritional status as defined by either a BMI < 18.5 and/or baseline albumin < 3.5 mg/dL had a median PFS of 2.2 months compared to those who did not of 5.2 months (p < 0.00032). Conclusions: In this single institution retrospective review, BMI or albumin as solitary factors did not have a significant effect on outcomes receiving immunotherapy in lung cancer patients. However, a more comprehensive nutritional assessment using a composite endpoint of BMI and serum albumin predicted response to checkpoint inhibitors. Additional studies are needed to validate these findings.