Clinical Application of Blocker Displacement Amplification Technique Combined with Next Generation Sequencing in Liquid Biopsy of Advanced Non-Small Cell Lung Cancer with Positive Anaplastic Lymphoma Kinase and Repressor of Silencing 1 Fusion Genes

Abstract

Objective: To evaluate the value of the blocker displacement amplification (BDA) technique combined with next generation sequencing (NGS) liquid biopsy in the diagnosis and treatment of anaplastic lymphoma kinase (ALK)-positive and repressor of silencing 1 (ROS1)-positive advanced non-small cell lung cancer. The hope is to provide new guidance for targeted treatment of advanced non-small cell lung cancer patients with ALK and ROS1 fusion gene positive, especially when tissue samples are not timely or IHC (immunohistochemistry) detection results are uncertain. Methods: Analyze the background features of the study groups. BDA-NGS was used to detect ALK and ROS1 fusion genes in peripheral blood of 248 patients (include RNA extraction and reverse transcription of peripheral blood vesicles, amplification and enrichment of BDA target regions and product recovery, NGS detection). The expression of ALK and ROS1 was detected by immunohistochemistry (IHC) in tumor tissues from the same patients. Results: In 248 paired samples of IHC and peripheral blood BDA-NGS test, the detection rate of positive ALK/ROS1 by IHC was significantly higher than that by peripheral blood BDA-NGS test (54.84% vs 36.29%, p < 0.001). The positive ALK/ROS1 results by two test methods exhibited moderate consistency (Kappa = 0.651, 0.738, p <0.001 and p < 0.001). Conclusions: Blood samples can be used as substitutes for testing when tissue samples are not available. Moreover, peripheral blood BDA-NGS test can complement solid tumor tissue biopsy to guide the rational drug use in clinic.