Introduction and impact of routine whole genome sequencing in the diagnosis and management of sarcoma

Abstract

Background Sarcomas are diverse neoplasms with highly variable histological appearances in which diagnosis is often challenging and management options for metastatic/unresectable disease limited. Many sarcomas have distinctive molecular alterations, but the range of alterations is large, variable in type and rapidly increasing, meaning that testing by limited panels is unable to capture the broad spectrum of clinically pertinent genomic drivers required. Paired whole genome sequencing (WGS) in contrast allows comprehensive assessment of small variants, copy number and structural variants along with mutational signature analysis and germline testing. Methods Introduction of WGS as a diagnostic standard for all eligible patients with known or suspected soft tissue sarcoma over a 2-year period at a soft tissue sarcoma treatment centre. Results WGS resulted in a refinement in the diagnosis in 37% of cases, identification of a target for personalised therapy in 33% of cases, and a germline alteration in 4% of cases. Conclusion Introduction of WGS poses logistical and training challenges, but offers significant benefits to this group of patients.