title: Gastrointestinal stromal tumors: usefulness of immunohistochemistry, flow cytometry and fluorescence in situ hybridization.
abstract: OBJECTIVE
  Gastrointestinal stromal tumors (GIST) constitute a group of primary mesenchymal tumors of the gastrointestinal tract, known for their diversity in clinical behavior and the difficulties in determining malignancy and prognosis. This retrospective study evaluated a series of GIST by means of immunohistochemical techniques, flow cytometry and fluorescence in situ hybridization (FISH).
  
  
  METHODS
  Nine patients with GIST were analyzed for tumor size, mitotic count and CD117, CD34, MIB-1 with immunohistochemistry. In addition, the GIST were tested with FISH for chromosomes 8 and 17 and DNA index was evaluated by flow cytometry.
  
  
  RESULTS
  The findings confirmed the usefulness of CD117 and CD34 in diagnosing GIST and the prognostic role of MIB-1, but do not support a correlation between aneuploidy in flow cytometry and poor outcome. The FISH results suggest close follow-up for patients with benign GIST with a numerical alteration of chromosome 8. The technique could select patients with tumors at high-risk with aneusomy of chromosome 17.
  
  
  CONCLUSIONS
  This study shows the possible application of FISH to the evaluation of patients with GIST, in addition to analysis of morphological features.
authors.affiliation: First Department of Surgery, University of Brescia, Brescia, Italy.
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Fontana
authors.forename: Elisa
authors.initials: E
authors.lastname: Rossi
authors.forename: Gabrio
authors.initials: G
authors.lastname: Bassotti
authors.forename: Maria Costanza
authors.initials: MC
authors.lastname: Aquilano
authors.forename: Morris
authors.initials: M
authors.lastname: Cadei
authors.forename: Piergiovanni
authors.initials: P
authors.lastname: Grigolato
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Villanacci
mesh_terms: D018952:Antigens, CD34 / Q000032:analysis; D002886:Chromosomes, Human, Pair 17; D002898:Chromosomes, Human, Pair 8; D005260:Female; D005434:Flow Cytometry; D005500:Follow-Up Studies; D046152:Gastrointestinal Stromal Tumors / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology / Q000628:therapy; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D019394:Ki-67 Antigen / Q000032:analysis; D008297:Male; D008875:Middle Aged; D008940:Mitotic Index; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D011379:Prognosis; D019009:Proto-Oncogene Proteins c-kit / Q000032:analysis; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D018952:Antigens, CD34; D019394:Ki-67 Antigen; D019009:Proto-Oncogene Proteins c-kit