Abstract 1972: The significance of liquid biopsy in colorectal cancer via GeneReader NGS Systems

Abstract

Abstract Background: In terms of precision medicine, not only tumoral tissue samples but also with liquid biopsy for somatic variants detection, have been used routinely. It also helps to overcome the resampling difficulties that require an invasive procedure with the problem of tumor heterogeneity. With the Next Generation Sequencing (NGS) method which is accepted as the gold standard in molecular genetic testing, colorectal cancer patients ccfDNA (Circulating Cell-Free DNA) samples were next generation sequenced via a targeted multigene panel. Methods: In our study, liquid biopsy samples of 63 colorectal cancer patients whom referred to Cukurova University AGENTEM (Adana Genetic Diseases Diagnosis and Treatment Center) were sequenced via GeneReader NGS Systems (Qiagen). The multi-gene panel which includes cancer related actionable 11 genes (KRAS, NRAS, KIT, BRAF, PDGFRA, ALK, EGFR, ERBB2, ERBB3, ESR1 and RAF1) were used to identify the variants of drug sensitivity and resistance. Sequencing data were analyzed by QCI-Analyze and QCI-Interpret bioinformatics tools. Results: Forty-three clinically significant variants detected in 53.96% (n=34) of 63 patients. Total of 43 clinically significant variants in 7 genes (KRAS, NRAS, KIT, BRAF, EGFR, PDGFRA and ERBB2) were detected according to the ACMG (American College of Medical Genetics) and AMP (Association for Molecular Pathology) criteria in which 13.95%, 41.86% and 41.86% prospectively related to drug resistance, treatment sensitivity, and both treatment sensitivity and drug resistance. Moreover, 2.33% were classified as uncertain clinical significance due to data mining. Variants detected upon gene names were listed in Table 1. Table 1:Genes and variants distribution in colorectal cancer patientsGene NameVariantsTotal %KRASp.G12A,p.G12C,p.G12D,p.G12V,p.G13S,p.G15S,p.A18V,p.I21M,p.A59T,p.A146T32.56KITp.M541L20.93BRAFp.T559I,p.V600E,p.K601R,p.R603*,p.P632S,p.639I20.93EGFRp.E282K,p.H773R,p.H773P,p.V834A,p.G863D11.63PDGFRAp.E241A,p.Y555H4.65NRASp.G13C,p.E31V,p.Q61R6.98ERBB2p.P1170V2.33 Conclusion: In terms of identifying potential target therapy options without the need of a invasive intervention becomes available with NGS multigene panel studies within high reliability that also have an effect on the quality of life in colorectal cancer patients. Citation Format: Cem Mujde, Abdullah Hanta, Ozge Sonmezler, Ahmet Rencuzogullari, Ibrahim Boga, Atil Bisgin. The significance of liquid biopsy in colorectal cancer via GeneReader NGS Systems [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1972.