title: Cyclooxygenase-2 expression and clinical outcome in gastrointestinal stromal tumors.
abstract: The significance of cyclooxygenase-2 (COX-2) expression in mesenchymal tumors has not been completely described. We analyzed clinicopathologic variables and COX-2 protein expression in all mesenchymal tumors of the GI tract that were treated at our institution between 1990 and 2002. Paraffin-embedded specimens were immunohistochemically stained for KIT and COX-2 protein. KIT-positive tumors were diagnosed as gastrointestinal stromal tumors (GIST). Among 42 available specimens, 38 tumors were diagnosed as GIST and four were non-GIST mesenchymal GI tumors (KIT negative). The median overall survival for the GIST patients was 34 months. Ninety-two percent of GIST expressed COX-2 protein. COX-2 protein was not expressed in any of the non-GIST tumors. GIST patients with negative or low COX-2 expression developed disease recurrence and/or died of their disease in 37% of the cases, compared with 18% for GIST patients with high COX-2 expression (difference not statistically significant). The vast majority of mesenchymal tumors of the GI tract are GIST that express COX-2 protein. As opposed to known predictors of GIST behavior such as tumor size and mitotic count, levels of COX-2 protein expression did not correlate with clinical outcome.
authors.affiliation: Department of Surgery, University of Alabama at Birmingham, 1922 7th Avenue South, Birmingham, AL 35294, USA.
authors.forename: Ashley E
authors.initials: AE
authors.lastname: Stewart
authors.forename: Martin H
authors.initials: MH
authors.lastname: Heslin
authors.forename: Jorge
authors.initials: J
authors.lastname: Arch
authors.forename: Nirag
authors.initials: N
authors.lastname: Jhala
authors.forename: Brian
authors.initials: B
authors.lastname: Ragland
authors.forename: Fernando
authors.initials: F
authors.lastname: Gomez
authors.forename: Kirby I
authors.initials: KI
authors.lastname: Bland
authors.forename: J Pablo
authors.initials: JP
authors.lastname: Arnoletti
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D002423:Cause of Death; D051546:Cyclooxygenase 2 / Q000032:analysis*; D005260:Female; D005500:Follow-Up Studies; D005770:Gastrointestinal Neoplasms / Q000201:enzymology / Q000473:pathology / Q000601:surgery; D046152:Gastrointestinal Stromal Tumors / Q000201:enzymology* / Q000473:pathology / Q000601:surgery; D006801:Humans; D008297:Male; D008637:Mesenchymoma / Q000201:enzymology / Q000473:pathology / Q000601:surgery; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D011379:Prognosis; D019009:Proto-Oncogene Proteins c-kit / Q000032:analysis; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D051546:Cyclooxygenase 2; D019009:Proto-Oncogene Proteins c-kit