title: Circulating Tumor DNA Analysis for Liver Cancers and Its Usefulness as a Liquid Biopsy.
abstract: OBJECTIVE
  Circulating tumor DNA (ctDNA) carrying tumor-specific sequence alterations has been found in the cell-free fraction of blood. Liver cancer tumor specimens are difficult to obtain, and noninvasive methods are required to assess cancer progression and characterize underlying genomic features.
  
  
  METHODS
  We analyzed 46 patients with hepatocellular carcinoma who underwent hepatectomy or liver transplantation and for whom whole-genome sequencing data was available. We designed personalized assays targeting somatic rearrangements of each tumor to quantify serum ctDNA. Exome sequencing was performed using cell-free DNA paired primary tumor tissue DNA from a patient with recurrent liver cancer after transcatheter arterial chemoembolization (TACE).
  
  
  RESULTS
  We successfully detected ctDNA from 100 μL of serum samples in 7 of the 46 patients before surgery, increasing with disease progression. The cumulative incidence of recurrence and extrahepatic metastasis in the ctDNA-positive group were statistically significantly worse than in the ctDNA-negative group (P= .0102 and .0386, respectively). Multivariate analysis identified ctDNA (OR 6.10; 95% CI, 1.11-33.33,P= .038) as an independent predictor of microscopic vascular invasion of the portal vein (VP). We identified 45 nonsynonymous somatic mutations in cell-free DNA after TACE and 71 nonsynonymous somatic mutations in primary tumor tissue by exome sequencing. We identified 25 common mutations in both samples, and 83% of mutations identified in the primary tumor could be detected in the cell-free DNA.
  
  
  CONCLUSIONS
  The presence of ctDNA reflects tumor progression, and detection of ctDNA can predict VP and recurrence, especially extrahepatic metastasis within 2 years. Our study demonstrated the usefulness of ctDNA detection and sequencing analysis of cell-free DNA for personalized treatment of liver cancer.
authors.affiliation: Department of Gastroenterology and Metabolism, Applied Life Science, Institute of Biomedical and Health Science, Hiroshima University, Hiroshima, Japan; Liver Research Project Center, Hiroshima University, Hiroshima, Japan; Laboratory for Digestive Diseases, RIKEN Center for Integrative Medical Sciences, Hiroshima, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ono
authors.affiliation: Laboratory for Genome Sequencing Analysis, RIKEN Center for Integrative Medical Sciences, Tokyo, Japan; Laboratory for Medical Science Mathematics, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Fujimoto
authors.affiliation: Laboratory for Genome Sequencing Analysis, RIKEN Center for Integrative Medical Sciences, Tokyo, Japan.
authors.forename: Yujiro
authors.initials: Y
authors.lastname: Yamamoto
authors.affiliation: Department of Gastroenterology and Metabolism, Applied Life Science, Institute of Biomedical and Health Science, Hiroshima University, Hiroshima, Japan; Liver Research Project Center, Hiroshima University, Hiroshima, Japan; Laboratory for Digestive Diseases, RIKEN Center for Integrative Medical Sciences, Hiroshima, Japan.
authors.forename: Sakura
authors.initials: S
authors.lastname: Akamatsu
authors.affiliation: Department of Gastroenterology and Metabolism, Applied Life Science, Institute of Biomedical and Health Science, Hiroshima University, Hiroshima, Japan; Liver Research Project Center, Hiroshima University, Hiroshima, Japan.
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Hiraga
authors.affiliation: Department of Gastroenterology and Metabolism, Applied Life Science, Institute of Biomedical and Health Science, Hiroshima University, Hiroshima, Japan; Liver Research Project Center, Hiroshima University, Hiroshima, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Imamura
authors.affiliation: Department of Gastroenterology and Metabolism, Applied Life Science, Institute of Biomedical and Health Science, Hiroshima University, Hiroshima, Japan; Liver Research Project Center, Hiroshima University, Hiroshima, Japan.
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Kawaoka
authors.affiliation: Department of Gastroenterology and Metabolism, Applied Life Science, Institute of Biomedical and Health Science, Hiroshima University, Hiroshima, Japan; Liver Research Project Center, Hiroshima University, Hiroshima, Japan.
authors.forename: Masataka
authors.initials: M
authors.lastname: Tsuge
authors.affiliation: Department of Gastroenterology and Metabolism, Applied Life Science, Institute of Biomedical and Health Science, Hiroshima University, Hiroshima, Japan; Liver Research Project Center, Hiroshima University, Hiroshima, Japan; Laboratory for Digestive Diseases, RIKEN Center for Integrative Medical Sciences, Hiroshima, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Abe
authors.affiliation: Department of Gastroenterology and Metabolism, Applied Life Science, Institute of Biomedical and Health Science, Hiroshima University, Hiroshima, Japan; Liver Research Project Center, Hiroshima University, Hiroshima, Japan; Laboratory for Digestive Diseases, RIKEN Center for Integrative Medical Sciences, Hiroshima, Japan.
authors.forename: C Nelson
authors.initials: CN
authors.lastname: Hayes
authors.affiliation: Liver Research Project Center, Hiroshima University, Hiroshima, Japan; Laboratory for Digestive Diseases, RIKEN Center for Integrative Medical Sciences, Hiroshima, Japan.
authors.forename: Daiki
authors.initials: D
authors.lastname: Miki
authors.affiliation: Laboratory for Genome Sequencing Analysis, RIKEN Center for Integrative Medical Sciences, Tokyo, Japan.
authors.forename: Mayuko
authors.initials: M
authors.lastname: Furuta
authors.affiliation: Laboratory for Medical Science Mathematics, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan.
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Tsunoda
authors.affiliation: Laboratory of DNA Information Analysis, Human Genome Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Miyano
authors.affiliation: Laboratory for Genotyping Development, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan.
authors.forename: Michiaki
authors.initials: M
authors.lastname: Kubo
authors.affiliation: Department of Gastroenterology and Metabolism, Applied Life Science, Institute of Biomedical and Health Science, Hiroshima University, Hiroshima, Japan; Liver Research Project Center, Hiroshima University, Hiroshima, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Aikata
authors.affiliation: Department of Gastroenterology and Metabolism, Applied Life Science, Institute of Biomedical and Health Science, Hiroshima University, Hiroshima, Japan; Liver Research Project Center, Hiroshima University, Hiroshima, Japan; Laboratory for Digestive Diseases, RIKEN Center for Integrative Medical Sciences, Hiroshima, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Ochi
authors.affiliation: Department of Gastroenterology and Metabolism, Applied Life Science, Institute of Biomedical and Health Science, Hiroshima University, Hiroshima, Japan; Liver Research Project Center, Hiroshima University, Hiroshima, Japan.
authors.forename: Yoshi-Iku
authors.initials: YI
authors.lastname: Kawakami
authors.affiliation: Department of Anatomical Pathology, Hiroshima University School of Medicine, Hiroshima, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Arihiro
authors.affiliation: Department of Gastroenterological Surgery, Hiroshima University School of Medicine, Hiroshima, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Ohdan
authors.affiliation: Laboratory for Genome Sequencing Analysis, RIKEN Center for Integrative Medical Sciences, Tokyo, Japan.
authors.forename: Hidewaki
authors.initials: H
authors.lastname: Nakagawa
authors.affiliation: Department of Gastroenterology and Metabolism, Applied Life Science, Institute of Biomedical and Health Science, Hiroshima University, Hiroshima, Japan; Liver Research Project Center, Hiroshima University, Hiroshima, Japan; Laboratory for Digestive Diseases, RIKEN Center for Integrative Medical Sciences, Hiroshima, Japan.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Chayama
keywords: AFP, α-fetoprotein; ALT, alanine aminotransferase; AST, aspartate aminotransferase; Circulating Tumor DNA; DCP, des-γ-carboxy prothrombin; Exome Sequencing; HAIC, hepatic arterial infusion chemotherapy; HBV, hepatitis B virus; HCC, hepatocellular carcinoma; HCV, hepatitis C virus; Hepatocellular Carcinoma; PCR, polymerase-chain-reaction; TACE, transcatheter arterial chemoembolization; VP, microscopic vascular invasion to portal vein; Whole-Genome Sequencing; cHCC/CC, combined hepatocellular and cholangiocarcinoma; ctDNA, circulating tumor DNA