Impact of Body Mass Index on Outcomes in an Asian population of Advanced Renal Cell Carcinoma and Urothelial Carcinoma Treated With Immune Checkpoint Inhibitors

Abstract

Objectives: To clarify the impact of body mass index (BMI) on treatment outcomes including survival, tumor response, and adverse events (AEs) in patients with advanced renal cell carcinoma (RCC) or urothelial carcinoma (UC) treated with immune checkpoint inhibitors (ICIs) in an Asian population.

Methods: We retrospectively evaluated 309 patients with advanced RCC or UC who received ICIs between September 2016 and July 2021. The patients were divided into high- (i.e., ≥25 kg/m²) and low-BMI (<25 kg/m²) groups according to the BMI at the time of treatment initiation.

Results: Overall, 57 patients (18.4%) were classified into the high-BMI group. In RCC patients treated with ICIs as first-line therapy or UC treated with pembrolizumab, progression-free survival (PFS) (p = 0.309; p = 0.842), overall survival (OS) (p = 0.701; p = 0.983), and objective response rate (ORR) (p = 0.163; p = 0.553) were comparable between the high- and low-BMI groups. In RCC patients treated with nivolumab monotherapy as later-line therapy, OS (p = 0.101) and ORR (p = 0.102) were comparable, but PFS was significantly longer in the high-BMI group (p = 0.0272). Further, multivariate analysis showed that BMI was not an independent factor of PFS or OS in all the treatment groups (any, p>0.05). As for AE profiles, in nivolumab monotherapy, the rate was significantly higher in the high-BMI group (p = 0.0203), whereas in the other two treatments, the rate was comparable.

Conclusions: BMI was not associated with survival or response rates of advanced RCC or UC patients treated with ICIs in an Asian population. AEs might frequently develop in high-BMI patients with RCC in nivolumab monotherapy.

Keywords: Avelumab; Axitinib; Ipilimumab; Nivolumab; Obesity; Pembrolizumab.