Mutations in gastrointestinal stromal tumors diagnosed by endoscopic ultrasound-guided fine needle aspiration.
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.
Schmitt
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FC
IPATIMUP and Medical Faculty of Porto University, Porto, Portugal. fernando.schmitt@ipatimup.pt
Gomes
A L
AL
Milanezi
F
F
Reis
R
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Bardales
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RH
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
D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D047428:Protein Kinase Inhibitors; D011743:Pyrimidines; D000068877:Imatinib Mesylate; D019009:Proto-Oncogene Proteins c-kit