Prognostic factors of extragastrointestinal stromal tumors

Objective To explore clinical features and prognostic factors of extragastrointestinal stromal tumors (EGIST). Methods The clinical and follow-up data of 47 patients with extragastrointestinal stromal tumors admitted to Liaoning Cancer Hospital for the first time from November 2006 to May 2017 were retrospectively analyzed, and compared with 254 cases of gastrointestinal stromal tumor (GIST) in our center. Results EGIST and GIST patients showed significant differences in age (χ2=6.394, P<0.011), tumor size (χ2=60.941, P<0.001), histological type (χ2=30.081, P<0.001), CD117 expression (χ2=52.99, P<0.001), CD34 expression (χ2=37.21, P<0.001), Dog-1 expression (χ2=24.57, P<0.001), necrosis (χ2=10.38, P=0.006), and NIH score (χ2=56.12, P<0.001). One year, two years and three years survival rates of all EGIST patients were 84.6%、78.3%、63.4% respectively; 25 patients(51.4%) were with R0 resection. The survival rate of patients with R0 resection was significantly higher than that of patients without R0 resection (χ2=5.104, P=0.024). Among them, the prognosis of 25 patients with R0 resection showed no statistical significance in patients with different mitotic figures, tumor diameters, necrosis (χ2=2.067, P=0.151; χ2=1.35, P=0.244; χ2=0.912, P=0.34). Conclusion EGIST symptoms are dormant and difficult to diagnose, with large volume at first. R0 resection is associated with prognosis. Key words: Extragastrointestinal stromal tumor (EGIST); Gastrointestinal stromal tumor (GIST); Clinical features; Survival; Prognosis factors