Yanbing Zhou, Liang Ning, Shougen Cao. Affiliated Hospital of Qingdao University
Objective: To investigate the clinicopathologic features and prognosis of patients with gastrointestinal stromal tumor (GIST) after surgery in Shandong Province.
Methods: The clinicopathological data of gastrointestinal stromal tumor with immunohistochemical CD117 positive or DOG-1 positive were collected from January 2001 to June 2013 in four University Teaching Hospitals in Shandong Province. The prognostic factors were evaluated by univariate and multivariate analysis with Log-rank test and Cox proportional hazard model respectively.
Results: A total of 1039 cases were retrieved, including 509 males and 530 females. The age ranged from 18 to 87 years (median 58). 93 patients died from GIST. The 1-, 3-, 5-year survival rates were 94.6%,91.7% and 87.8%, respectively. Patients underwent R0 resection had a higher 5-year overall survival rate than patients underwent R1 resection (88.8% vs 69.0%, P<0.05). For patients with intermediate risk to relapse after surgery, the 5-year overall survival rate was 94.4% and 89.2% individually in imatinib and no-imatinib intervention group (P>0.05). For patients with high risk to relapse after surgery, the 5-year overall survival rate was 76.8% and 67.7% (P<0.05) separately. On multivariate analysis, tumor size (P<0.01,RR=1.988,95%CI: 1.497-2.641), mitotic count (P<0.01,RR=2.326,95%CI: 1.686-3.208) and rupture or not (P<0.01,RR=3.032,95%CI: 1.732-5.308) were independent prognostic factors.
Conclusions: Tumor size, mitotic count and rupture or not affect the prognosis of patients after resection of primary GIST independently. The standard treatment of localized GIST is R0 resection. Adjuvant imatinib can improve overall survival of patients with high risk to relapse after surgery. The efficacy of imatinib for patients with intermediate risk to recurrence remains to be verified.
Keywords: GIST, Imatinib, Prognosis