Body mass index (BMI) and toxicities and association with clinical outcomes (CO) in metastatic renal cell carcinoma (mRCC) patients (pts) treated with cabozantinib (cabo).

Abstract

613 Background: BMI has been explored as a prognostic factor in cancer pts and treatment-related toxicities have been associated with responses to VEGF-targeted therapy in mRCC pts. We investigated the association of BMI and adverse events (AEs) and CO in mRCC pts treated with cabo. Methods: A retrospective analysis of 65 pts with mRCC treated with cabo at Winship Cancer Institute from 2016 to 2018 was performed. Overall survival (OS), progression-free survival (PFS), and objective response (OR) were used to measure CO. OS and PFS were calculated from first cabo dose to death and radiographic or clinical progression, respectively. An OR was defined as a partial response (PR) or a complete response (CR) using RECISTv1.1. BMI was collected at baseline (BL) and 6 (±2) weeks after cabo initiation. AEs were obtained from clinic notes. Univariate analysis (UVA) of association between BMI and CO was carried out using logistic regression model for OR and proportional hazard model for OS and PFS. Results: The median age was 63 years and 26% were African American. The majority were either IMDC intermediate or poor-risk (59% and 34%, respectively). Most pts (67%) had a BMI ≥ 25 and the median BMI at BL was 26.6. There was no difference in incidence of AEs between pts with BMI < 25 and pts with BMI ≥ 25. Gastrointestinal (GI) AEs incidence was also comparable among pts with a BMI ≥ 25 (62%) and pts with BMI < 25 (57%, p = 0.666). Increased BMI at 6W was significantly associated with prolonged OS and increased baseline BMI at BL showed a trend towards longer OS (Table). Conclusions: Increased BMI may be associated with improved CO in mRCC pts treated with cabo, but there may not be a difference in AEs based on BMI. Larger analyses are needed to validate these findings. [Table: see text]