title: Clinical Utility of Circulating Tumor DNA for Molecular Assessment and Precision Medicine in Pancreatic Cancer.
abstract: Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal malignancies. The genomic landscape of the PDAC genome features four frequently mutated genes (KRAS, CDKN2A, TP53, and SMAD4) and dozens of candidate driver genes altered at low frequency, including potential clinical targets. Circulating cell-free DNA (cfDNA) is a promising resource to detect molecular characteristics of tumors, supporting the concept of "liquid biopsy".We determined the mutational status of KRAS in plasma cfDNA using multiplex droplet digital PCR in 259 patients with PDAC, retrospectively. Furthermore, we constructed a novel modified SureSelect-KAPA-Illumina platform and an original panel of 60 genes. We then performed targeted deep sequencing of cfDNA in 48 patients who had ≥1 % mutant allele frequencies of KRAS in plasma cfDNA.Droplet digital PCR detected KRAS mutations in plasma cfDNA in 63 of 107 (58.9 %) patients with inoperable tumors. Importantly, potentially targetable somatic mutations were identified in 14 of 48 patients (29.2 %) examined by cfDNA sequencing.Our two-step approach with plasma cfDNA, combining droplet digital PCR and targeted deep sequencing, is a feasible clinical approach. Assessment of mutations in plasma cfDNA may provide a new diagnostic tool, assisting decisions for optimal therapeutic strategies for PDAC patients.
authors.affiliation: Division of Cancer Genomics, National Cancer Center Research Institute, Tokyo, Japan. ertakai@ncc.go.jp.
authors.forename: Erina
authors.initials: E
authors.lastname: Takai
authors.affiliation: Division of Cancer Genomics, National Cancer Center Research Institute, Tokyo, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Totoki
authors.affiliation: Division of Cancer Genomics, National Cancer Center Research Institute, Tokyo, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Nakamura
authors.affiliation: Division of Cancer Genomics, National Cancer Center Research Institute, Tokyo, Japan.
authors.forename: Mamoru
authors.initials: M
authors.lastname: Kato
authors.affiliation: Laboratory of Molecular Medicine, Human Genome Center, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.
authors.forename: Tatsuhiro
authors.initials: T
authors.lastname: Shibata
authors.affiliation: Division of Cancer Genomics, National Cancer Center Research Institute, Tokyo, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Yachida
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood / Q000235:genetics; D021441:Carcinoma, Pancreatic Ductal / Q000097:blood / Q000175:diagnosis / Q000235:genetics*; D004273:DNA, Neoplasm / Q000097:blood / Q000235:genetics*; D005260:Female; D059014:High-Throughput Nucleotide Sequencing / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D009154:Mutation; D010190:Pancreatic Neoplasms / Q000097:blood / Q000175:diagnosis / Q000235:genetics*; D057285:Precision Medicine / Q000379:methods*; D011379:Prognosis; D016283:Proto-Oncogene Proteins p21(ras) / Q000235:genetics; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; C117307:KRAS protein, human; D016283:Proto-Oncogene Proteins p21(ras)
keywords: Pancreatic cancer; Plasma cfDNA; Targeted deep sequencing