Abstract 544: Urine as a non-invasive alternative to blood for germline and somatic mutation detection in hepatocellular carcinoma

Abstract BACKGROUND: Cell-free DNA (cfDNA) from blood has become a promising analyte for cancer diagnostics. However, because blood contains high concentrations of proteins and enzyme inhibitors, plasma cfDNA quality can be variable. Urinary cfDNA has been shown to contain mutations associated with non-genitourologic cancers including hepatocellular carcinoma (HCC). In this study, we evaluate urine as a noninvasive alternative to blood-based liquid biopsy for both germline and ctDNA genotyping in HCC. METHOD: Using qPCR, whole-genome sequencing (WGS), and targeted NGS, DNA isolated from blood or urine of patients with HCC was evaluated and analyzed for overall genome coverage, HCC hotspot coverage, and germline or somatic mutation concordance. Targeted NGS of plasma and urine cfDNA was also performed for detection of somatic variants. RESULTS: Similar to plasma cfDNA, urine cfDNA showed a major mononucleosomal species of 165-170 bp, with dinucleosomal species also discernable in most healthy individuals and patients with HCC. Overall genome coverage breadth was similar between urine and plasma cfDNA, with higher fraction of covered cancer-associated mutation hotspots in urine cfDNA. Quantitative PCR analyses of HCC-associated mutations (TP53, CTNNB1, and hTERT) in 102 patients with HCC, revealed 78% overall concordance between plasma and urine. Targeted NGS of HCC-associated gene regions in additional 15 patients showed an 97% overall position-level concordance between plasma and urine cfDNA. Furthermore, urine outperformed plasma in both the sensitivity and specificity of detection of CTNNB1 and hTERT mutations. CONCLUSION urine DNA can potentially be used as a completely noninvasive diagnostic biomarker for HCC. Citation Format: Amy Kim, Selena Lin, Yixiao Cui, Terence Gade, Fwu-Shan Shieh, Max Chao, John Shieh, Surbhi Jain, Jonathan Cheng, James Hamilton, Hie-Won L. Hann, Dmitry Goryunov, Ying-Hsiu Su. Urine as a non-invasive alternative to blood for germline and somatic mutation detection in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 544.