title: [CD117 contribution in the diagnosic of mesenchymal tumors of the digestive tract].
abstract: Gastrointestinal stromal tumor (GIST) is a new distinct entity defined as CDI 17 or c-kit positive mesenchymal tumors, originaling in gastrointestinal pacemaker cells known as interstitial cells of Cajal. This study evaluate the percentage of GIST previously diagnosed as mesenchymal tumors in our hospital during 11 years.
  
  
  METHODS
  A total of 30 surgically resected gastrointestinal tumor specimens were collected from January 1990 to December 2000 in the pathology laboratory of la Rabta Jospital. Immunohistochemical studies were performed on these tumors with antibodies of CD 117, smooth muscle actin (SMA) and protein S-100.
  
  
  RESULTS
  Among the 30 tumors, 26 (86.6%) were CD117 positive and were classified as gastrointestinal stromal tumors. Among the 26 GIST, SMA was positive in 11 tumors (42.3%), 6 tumors (23%) expressed protein S-100. The 4 tumors classified as non-GIST were leiomyomas with the following immunohistochemical characteristics: CD117-negative with strong SMA-positive and protein S100 negative status.
  
  
  CONCLUSIONS
  The majority (86.6%) of mesenchymal gastrointestinal tumors were GIST, except for a smalls groups of smooth muscle tumors.
authors.affiliation: Service d'anatomie pathologique, hôpital la Rabta, 1007 Bab Saadoun, Tunis, Tunisie.
authors.forename: Bellil
authors.initials: B
authors.lastname: Khadija
authors.forename: Bouraoui
authors.initials: B
authors.lastname: Saadia
authors.forename: Chelly
authors.initials: C
authors.lastname: Ines
authors.forename: Karoui
authors.initials: K
authors.lastname: Sami
authors.forename: Jouini
authors.initials: J
authors.lastname: Mohamed
authors.forename: Chikhaoui
authors.initials: C
authors.lastname: Zina
authors.forename: Kchir
authors.initials: K
authors.lastname: Nidhammeddine
authors.forename: M Zitouna
authors.initials: MZ
authors.lastname: Mohamed
authors.forename: Haouet
authors.initials: H
authors.lastname: Slim
mesh_terms: D000199:Actins / Q000032:analysis; D014408:Biomarkers, Tumor / Q000032:analysis*; D003937:Diagnosis, Differential; D005770:Gastrointestinal Neoplasms / Q000175:diagnosis / Q000473:pathology; D046152:Gastrointestinal Stromal Tumors / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D007889:Leiomyoma / Q000175:diagnosis / Q000473:pathology; D019009:Proto-Oncogene Proteins c-kit / Q000032:analysis*; D012189:Retrospective Studies; D009418:S100 Proteins / Q000032:analysis
chemical_list: D000199:Actins; D014408:Biomarkers, Tumor; D009418:S100 Proteins; D019009:Proto-Oncogene Proteins c-kit