title: Mutations in gastrointestinal stromal tumors diagnosed by endoscopic ultrasound-guided fine needle aspiration.
abstract: Gastrointestinal stromal tumors (GISTs) are characterized by overexpression and mutations of c-Kit. Approximately 80% of c-Kit mutations occur in exon 11, being a response factor to imatinib (Gleevec) therapy. We aimed to assess whether c-Kit and PDGFRA mutation analysis of GISTs obtained by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) could be routinely performed. Mutation analysis of c-Kit hotspot exons (9, 11, 13 and 17) and PDGFRA hotspot exons (12 and 18) was performed in aspirates 51 mesenchymal tumors. We identified c-Kit mutations in 61% of GIST cases, in accordance with previously published ranges (30-90%). Nearly 95% (19/20) of c-kit-mutant tumors carried exon 11 mutations. Mutation analysis is possible in FNA cell blocks and can assist in the diagnosis and therapeutic decisions in GIST cases.
authors.affiliation: IPATIMUP and Medical Faculty of Porto University, Porto, Portugal. fernando.schmitt@ipatimup.pt
authors.forename: F C
authors.initials: FC
authors.lastname: Schmitt
authors.forename: A L
authors.initials: AL
authors.lastname: Gomes
authors.forename: F
authors.initials: F
authors.lastname: Milanezi
authors.forename: R
authors.initials: R
authors.lastname: Reis
authors.forename: R H
authors.initials: RH
authors.lastname: Bardales
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001549:Benzamides; D044963:Biopsy, Fine-Needle / Q000379:methods; D019160:Endosonography; D005260:Female; D046152:Gastrointestinal Stromal Tumors / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D006801:Humans; D000068877:Imatinib Mesylate; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000627:therapeutic use; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics*; D011743:Pyrimidines / Q000627:therapeutic use
chemical_list: D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D047428:Protein Kinase Inhibitors; D011743:Pyrimidines; D000068877:Imatinib Mesylate; D019009:Proto-Oncogene Proteins c-kit