General practitioners' attitudes towards liquid biopsy as a diagnostic test for advanced lung cancer

In New Zealand (NZ), lung cancer disproportionately affects our indigenous Māori population, with both incidence and mortality being three times higher than NZ Europeans. Incidence of endothelial growth factor receptor (EGFR) mutated lung cancer is two to three times higher in Māori, Pacific and Asian people compared to NZ Europeans. Outcomes could potentially be improved if testing was augmented by biomarker testing of circulating tumour deoxyribonucleic acid (ctDNA) at the outset of diagnosis. Testing as a liquid biopsy could be more accessible, faster, and lower cost compared to tissue biopsy.We aimed to evaluate NZ General Practitioners' (GPs') attitudes towards liquid biopsy.

A survey was conducted of NZ GPs and was distributed through online channels between November 2023 to January 2024.

Seventy GPs responded and challenges reported with the diagnostic process of lung cancer were: limited GP appointments, poor access to imaging, and limited access to secondary care. 53/58 (91 %) of GPs were unaware of liquid biopsy. 46/58 (79 %) were initially not comfortable with pre-test genetic counselling associated for this. Some GPs highlighted the potential of liquid biopsy to complement existing procedures particularly in rural areas although concerns were expressed regarding culturally appropriate pathways. Provided adequate training and funding for liquid biopsy, 42/58 (72 %) of GPs stated they would be comfortable requesting liquid biopsy and the associated counselling.

Most GPs were not familiar with liquid biopsy but 72 % supported these tests to be incorporated into current pathways. Liquid biopsy could potentially reduce diagnostic delays and inequities in lung cancer.