Cyclooxygenase-2 expression and connection with tumor recurrence and histopathologic parameters in gastrointestinal stromal tumors.
Tissue cyclooxygenase-2 (COX-2) is a rate-limiting enzyme in prostaglandin synthesis and has been shown to have roles in carcinogenesis and tumor progression. Evaluation of COX-2 overexpression in malignancies has been performed mostly on tumors of epithelial origin, and little is known about its presence in mesenchymal tumors, especially gastrointestinal stromal tumors (GIST). COX-2 has been reported to be widely expressed in GIST and has been suggested as a potential diagnostic marker. We evaluated the overexpression and roles of COX-2 in tumorigenesis in GIST with regard to its relation to prognostic parameters and tumor recurrence. We studied the presence of COX-2 expression immunohistochemically and its relation to clinicopathologic prognostic variables in 41 cases of GIST. COX-2 was overexpressed in 21 (51%) of 41 tumors. The extent of overexpression was greater in tumors that recurred after surgical resection. COX-2 overexpression was also higher in tumors with coagulative necrosis, high mitotic index and an infiltrative pattern of growth. The observation of greater COX-2 expression levels in GIST with unfavorable histopathologic variables is contrary to previous reports and consistent with the reported roles of COX-2 in carcinogenesis of epithelial malignancies.
Türköz
Hüseyin Kemal
HK
Department of Pathology, Marmara University School of Medicine, Istanbul, Turkey. kemal.turkoz@marmara.edu.tr
Alkan
Ilhami
I
Sişman
Servet
S
Ozcan
Deniz
D
D000328:Adult; D000368:Aged; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000276:immunology*; D005260:Female; D046152:Gastrointestinal Stromal Tumors / Q000201:enzymology / Q000276:immunology*; D015971:Gene Expression Regulation, Enzymologic / Q000276:immunology*; D015972:Gene Expression Regulation, Neoplastic / Q000276:immunology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000201:enzymology / Q000276:immunology*; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D055815:Young Adult
D051546:Cyclooxygenase 2