Clinical characteristics, tumor genomic and transcriptomic profiles of patients (pts) with metastatic renal cell carcinoma (mRCC) who developed venous thromboembolism (VTE).

726 Background: VTE is a common complication in pts with mRCC. Identifying pts with mRCC at the highest risk of developing VTE may provide the rationale for initiating prophylactic anticoagulation. Methods: In this IRB-approved retrospective study, pts diagnosed with mRCC between 7/2012 and 7/2022 at Huntsman Cancer Institute at University of Utah were included. Variables evaluated were pts' clinical characteristics, treatment, and anticoagulation therapy. Pts with mRCC with VTE within 12 months after diagnosis were used as cases and those without VTE during the same period were used as control. The multivariable logistic model was used to assess risk factors of VTE. DeSeq2 analysis was implemented in Bioconductor Software to analyze differentially expressed genes based on the VTE. These results were subjected to gene ontology analysis in the TopGO software. All bioinformatic analysis was conducted in R-Studio, version 4.1.1. Results: Among 355 pts with mRCC, 53 pts developed VTE within 12 months after diagnosis (incidence rate: 14.9%). Pts of the two groups (with or without VTE) did not differ significantly when compared for age, gender, race, cytoreductive nephrectomy rate, clear cell histology, grade of tumor, IMDC risk factors (table). Pts who developed VTE had a higher BMI at diagnosis (31.7 vs. 29.1 kg/m2, p=0.03). In multivariate analysis, obesity (OR=1.06, [1.01-1.12], p=0.028) was associated with increased VTE risk. There was no significant difference of mutation rates in genomic panel. Transcriptomic analysis showed hormone metabolic, organic acid transport, extracellular matrix and structure organization (all p<0.0001) are among the most significantly elevated pathways associated with VTE. Correlation of genomic and transcriptomic data with occurrence of VTE will be presented in the meeting. Conclusions: In this real-world population of pts with mRCC, VTE is more commonly associated with mRCC than what was previously reported in clinical trials. These hypothesis generating data, upon external validation, may provide guidance for clinical use of prophylactic anticoagulation therapy in pts with mRCC.[Table: see text]