Clinicopathological Features and Prognosis of Gastrointestinal Stromal Tumors: A Study on 250 Cases

Abstract

The clinicopathological data, immunohistochemistry and partial genotyping of 250 patients with primary GIST treated in the Affiliated Hospital of Inner Mongolia Medical University from January 2013 to January 2018 were retrospectively analyzed. The results demonstrated that among the 250 patients in our hospital, 131 were male and 119 were female, aged from 20 to 86 years, with a median age of 60 years. It mainly occurred in the stomach (58.4%), and in the small intestine (24.0%). 171 cases of patients with mitotic count <5/50 HPF, and the rest of patients with mitotic count >5/50 HPF. 15 cases of patients with tumor diameter less than 2 cm, 88 cases of patients with 2-5 cm, 110 cases with 5.1-10 cm, and the others with tumor diameter larger than 10 cm. According to modified NIH criteria, the risk was divided into: 15 very low risk patients, 66 low risks, 68 intermediate risks and 110 high risk. The positive rates of immunohistochemical markers CD117, DOG-1 and CD34 were 96.4%, 90.4% and 77.2% respectively. There were significant differences in the expression of CD117 and DOG-1 in different tumor sizes and modified NIH criteria (P<0.05), and the expression of CD34 in different mitotic count (P<0.05). Among the 250 patients, 16 patients were treated with imatinib because of the large size and location of the tumors. 17 patients with metastasis mainly metastasized to the liver, the primary site was the stomach, and most of the metastasis patients had mutations in exon 11 of c-kit. The prognosis of small intestine and rectum after operation is obviously worse than those of stomach. The overall prognosis of this group is good and the results can objectively reflect the current situation of diagnosis and treatment of GIST in our hospital.