title: Multiple gastrointestinal stromal tumors: Clinicopathologic and genetic analysis of 12 patients.
abstract: Multiple gastrointestinal stromal tumors (GISTs) are extremely rare and usually associated with type 1 neurofibromatosis and familial GIST. The aim of this study was to investigate the clinical, phenotypic, and genetic characteristics of multiple GISTs to gain insights into their underlying pathogenesis and clinical behavior. Forty-seven paraffin blocks of multiple GISTs from 12 patients were analyzed. Genomic DNA was extracted from the tumor and normal mucosa and mutations for 4 exons of KIT gene and 3 exons of PDGFRA gene were determined. Among 12 patients with multiple GISTs, 5 were sporadic, 2 were familial with germline mutations of KIT gene, and 5 were associated with type 1 neurofibromatosis. All but 1 sporadic and familial multiple GISTs showed mutations of KIT gene shared by the same mutation on each GIST mass within a patient. But in 1 sporadic case, different types of KIT mutations were observed. Two familial multiple GIST cases showed diffuse involvement of the gastrointestinal tract with diffuse hyperplasia of interstitial cell of Cajal. Multiple GISTs associated with type 1 neurofibromatosis were located in the jejunum and harbored no mutations of KIT or PDGFRA. Different types of KIT gene mutation found in our case raise a possibility that recurrence of GISTs within a gastrointestinal tract may have a chance to be a rare occurrence of multiple primary GISTs instead of true recurrence. Multiple GISTs show unique clinical, phenotypic, and genotypic characteristics that are dependent on the particular underlying mechanisms, but the overall prognosis is favorable regardless of the numbers or phenotype of GISTs.
authors.affiliation: Department of Pathology, Chungnam National University, Korea.
authors.forename: Dae Young
authors.initials: DY
authors.lastname: Kang
authors.forename: Cheol Keun
authors.initials: CK
authors.lastname: Park
authors.forename: Jong Sang
authors.initials: JS
authors.lastname: Choi
authors.forename: So Young
authors.initials: SY
authors.lastname: Jin
authors.forename: Hyun Jung
authors.initials: HJ
authors.lastname: Kim
authors.forename: Mee
authors.initials: M
authors.lastname: Joo
authors.forename: Mi Seon
authors.initials: MS
authors.lastname: Kang
authors.forename: Woo Sung
authors.initials: WS
authors.lastname: Moon
authors.forename: Ki Jung
authors.initials: KJ
authors.lastname: Yun
authors.forename: Eun Sil
authors.initials: ES
authors.lastname: Yu
authors.forename: Haeyun
authors.initials: H
authors.lastname: Kang
authors.forename: Kyoung-Mee
authors.initials: KM
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D046152:Gastrointestinal Stromal Tumors / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*; D018095:Germ-Line Mutation; D006801:Humans; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000737:chemistry / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009378:Neoplasms, Multiple Primary / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*; D009456:Neurofibromatosis 1 / Q000235:genetics / Q000473:pathology; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics / Q000378:metabolism; D020796:Receptor, Platelet-Derived Growth Factor alpha / Q000235:genetics / Q000378:metabolism; D012189:Retrospective Studies
chemical_list: D004273:DNA, Neoplasm; D019009:Proto-Oncogene Proteins c-kit; D020796:Receptor, Platelet-Derived Growth Factor alpha