Analytical Validation of Next-Generation Sequencing-Based Comprehensive Liquid Biopsy Assay for Therapy Selection

Liquid biopsies are an increasingly important tool for the real-time monitoring of biomarkers, cancer recurrence, and disease burden in oncology practice. Tempus xF+ is a liquid biopsy assay that detects cell-free DNA in blood samples of patients with advanced solid tumors. The xF+ panel covers 523 genes spanning approximately 1.8 Mb of the human genome and can detect single-nucleotide variants and insertions-deletions in 522 genes. It also detects copy number gains in 7 genes and translocations (gene rearrangements) in 10 genes. Furthermore, the larger panel size allows for the calculation of blood tumor mutational burden. This work highlights the analytical validation performed for the xF+ assay, comparing it with a smaller panel liquid biopsy assay, calculating blood tumor mutational burden, and exploring its potential clinical utility.