Reporting Tumor Molecular Heterogeneity in Histopathological Diagnosis

作者：Andrea Mafficini, Eliana Amato, Matteo Fassan, Michele Simbolo, Davide Antonello, Caterina Vicentini, Maria Scardoni, Samantha Bersani, Marisa Gottardi, Borislav Chavdarov Rusev, Giorgio Malpeli, Vincenzo Corbo, Stefano Barbi, Katarzyna O. Sikora, Rita Teresa Lawlor, Giampaolo Tortora, Aldo Scarpa · 发表于：PLoS ONE · 年份：2014 · DOI：10.1371/journal.pone.0104979 · 被引用次数：39 · 研究领域：Cancer Genomics and Diagnostics、Genetic factors in colorectal cancer、Cancer Cells and Metastasis

BACKGROUND: Detection of molecular tumor heterogeneity has become of paramount importance with the advent of targeted therapies. Analysis for detection should be comprehensive, timely and based on routinely available tumor samples. AIM: To evaluate the diagnostic potential of targeted multigene next-generation sequencing (TM-NGS) in characterizing gastrointestinal cancer molecular heterogeneity. METHODS: 35 gastrointestinal tract tumors, five of each intestinal type gastric carcinomas, pancreatic ductal adenocarcinomas, pancreatic intraductal papillary mucinous neoplasms, ampulla of Vater carcinomas, hepatocellular carcinomas, cholangiocarcinomas, pancreatic solid pseudopapillary tumors were assessed for mutations in 46 cancer-associated genes, using Ion Torrent semiconductor-based TM-NGS. One ampulla of Vater carcinoma cell line and one hepatic carcinosarcoma served to assess assay sensitivity. TP53, PIK3CA, KRAS, and BRAF mutations were validated by conventional Sanger sequencing. RESULTS: TM-NGS yielded overlapping results on matched fresh-frozen and formalin-fixed paraffin-embedded (FFPE) tissues, with a mutation detection limit of 1% for fresh-frozen high molecular weight DNA and 2% for FFPE partially degraded DNA. At least one somatic mutation was observed in all tumors tested; multiple alterations were detected in 20/35 (57%) tumors. Seven cancers displayed significant differences in allelic frequencies for distinct mutations, indicating the presence of intratumor mole...