Lung cancer is the leading cause of cancer-related deaths in Canada, with non-small-cell lung cancer (NSCLC) accounting for the majority of cases. Timely access to comprehensive molecular profiling is critical for selecting biomarker-matched targeted therapies, which lead to improved outcomes in advanced NSCLC. Tissue biopsy samples are the gold standard for molecular profiling; however, several challenges can prevent timely and complete molecular profiling from being performed, causing delays in treatment or suboptimal therapy selection. Liquid biopsy offers a minimally invasive method for molecular profiling by analyzing circulating tumour DNA (ctDNA) and RNA (cfRNA) in plasma, potentially overcoming these barriers. This paper discusses the outcomes of a multidisciplinary working group in Ontario, which proposed three eligibility criteria for liquid biopsy reimbursement: (1) insufficient tissue for complete testing or failed tissue biomarker testing; (2) suspected advanced NSCLC where tissue biopsy is not feasible; and (3) high-risk patients who may deteriorate before tissue results are available. The group also addressed considerations for assay selection, implementation, and economic impact. These discussions aim to inform reimbursement and implementation strategies for liquid biopsy in Ontario's public healthcare system, recognizing the need for ongoing evaluation as technology and evidence evolve.
Keywords: circulating tumour DNA (ctDNA); liquid biopsy; molecular testing; non-small-cell lung cancer (NSCLC); targeted therapies.