A Clinicopathological Study Of Primary Gastrointestinal Stromal Tumor

Background Gastrointestinal stromal tumor is one kind of mesenchymal tumor with the specific expression of CD117 etc.The c-kit gene and PDGFRA gene mutations play an important role in the occurrence of GISTs.Recently,the most related research aims at GISTs occurred in stomach and small intestine.The study of GISTs in colorectum and out of the digestive tract is included in this article,in order to discuss the clinicopathological characteristics and prognostic factors of GISTs.Objective To discuss the clinicopathological characteristics and prognostic factors of the primary gastrointestinal stromal tumors.Methods 166 patients with GISTs admitted in Renji Hospital from December 2006 to March 2012 were analyzed retrospectively.The clinicopathological characteristics of GISTs in different sites was discussed.The progress-free survival(PFS)of GISTs patients were calculated by the Kaplan-Meier method.The potentially prognostic factors were investigated by univariate and multivariate analysis,respectively.Results There were 86 cases situated in stomach(51.8%),51 cases in small intestine(30.7%),12 cases in colorectum(7.2%)and 17 cases situated out of the digestive tract(10.3%).There were no significant difference in age,gender and symptoms between GISTs at different sites.Tumors in colorectum usually found <5cm during the surgery and with very low risk;however,Tumors out of the digestive tract usually found >10cm during the surgery and with high risk,which had worse prognosis(P<0.05).There were significant difference in c-kit gene mutation between different sites of GISTs(P<0.05).Univariate analysis revealed that primary location,tumor size,mitotic index,invasion of surrounding tissues,necrosis,risk ranking and Ki-67 index were related to the prognosis of GISTs(P<0.05);Multivariate analysis indicated that tumor size,mitotic index,invasion of surrounding tissues,necrosis,risk ranking and Ki-67 index were important prognostic factors for GISTs(P<0.05).Conclusion GISTs usually occurred in stomach and small intestine.Different sites of GISTs had its characteristics.Tumors occurred out of the digestive tract had worse prognosis than tumor situated in digestive tract.GISTs often showed c-kit gene mutation.There existed a certain degree of differences in gene mutation between different sites of GISTs.IT could combine NIH risk ranking,Ki-67 index and invasion of surrounding tissues to estimate the prognosis of GISTs.