Clinicopathologic, phenotypic, and genotypic characteristics of gastrointestinal mesenchymal tumors

摘要: Abstract Background & Aims: Variability in the frequency of KIT mutations gastrointestinal mesenchymal tumors has been reported literature, and their prognostic value remains uncertain. This retrospective multicenter study included 276 patients with tumors. Methods: We detected c-kit CD34 protein expression by immunohistochemistry. Mutations exons 11 9 12 18 PDGFR were length analysis polymerase chain reaction products direct DNA sequencing. Results: Eighty-seven percent analyzed positive, gastric expressing more frequently than other (86% vs. 52%; P exon 90 179 (50.3%) c-kit—positive 12% c-kit—negative These showed variation location. heterozygous 94% cases. frequent + − ( present 5.1% stromal tumors, 11% -nonmutated Patient's age, primary location, size, necrosis, mitotic counts associated metastases However, activity was only independent factor identified multivariate slightly metastatic nonmetastatic (61% 46%; = 0.06). Deletions codons 562–579 strongly deletions 550–561 0.0001). Conclusions: or 58.4% also some