Liquid Biopsy May Yield Diagnostic, Economic Benefits Over Tissue Biopsy in NSCLC

Jaime Rosenberg

The literature review included 25 studies related to diagnostic impact of liquid biopsies versus tissue biopsies and 3 studies that assessed the economic impacts of the 2 biopsies.

Liquid biopsy’s potential as a diagnostic in cancer is gaining recognition, and its advantages over tissue biopsy in non-small cell lung cancer (NSCLC) were featured in research recently presented at the annual meeting of the Academy of Managed Care Pharmacy (AMCP).

Based on their findings, the researchers suggest that liquid biopsy offers both diagnostic and economic benefits.

The literature review covered 25 studies that examined the diagnostic impact of liquid biopsies compared with tissue biopsies and 3 studies that assessed the economic impacts of the 2 biopsies. The researchers note that a comparison of liquid biopsy and tissue biopsy in the context of NSCLC is not well defined.

“Tissue biopsy (TBx) has been standard procedure for genetic analysis, but can be limited by the volume and quality of tissue samples required to test for multiple relevant targetable genes,” wrote the researchers. “Liquid biopsy (LBx) techniques, which can be used to test for circulating tumor DNA (ctDNA), circulating tumor cells, exosomes, platelets, and microRNAs, are less invasive for patients and potentially cheaper and faster than TBx techniques.”

The studies showed that LBx has a high specificity for identifying targetable mutations but may have lower sensitivity. There were 11 studies that reported a specificity of at least 90% for all tests and that specificity below 90% were seen most commonly with epidermal growth factor receptor T790M.

Sensitivity of the tests ranged significantly across the studies, as well as across mutations, with 14 of 19 studies reporting sensitivity of over 60% for all tests.

The 3 economic-focused studies all indicated that LBx was associated with lower costs for testing patients. In 1 US-based study, reduced costs totaled approximately $3000 per patient. The turnaround time from screening to treatment was lower with LBx, which was also associated with less complications, such as hemorrhage and respiratory distress.

According to the research authors, faster turnaround time seen with liquid biopsy and its high positive predictive values enable providers to make quicker treatment decisions for these patients with targetable mutations in NSCLC.

Reference

Zheng Y, Vioix H, Liu F, Singh B, Sharma S, Sharda D. Diagnostic and economic value of liquid versus solid tissue biopsy procedures for the detection of targetable mutations in non-small cell lung cancer (NSCLC) tumors: A literature review. Presented at: AMCP 2021; April 12-16, 2021. Abstract C10.