Whole exome sequencing of multi-regional biopsies from metastatic lesions to evaluate tumour heterogeneity and actionable truncal mutations using a radiologically-guided single-pass percutaneous technique.

To investigate the feasibility of obtaining multiple spatially-separated biopsies from a single lesion to identify actionable truncal mutations (ATMs). A maximum of 4 biopsies were obtained from each metastatic lesion and whole exome sequencing (WES) was performed. ATMs - filtered out using FoundationOne panel - were defined as variants detected in every biopsy from a patient and their associations with patient's outcome were assessed.