Objective: To analyze clinicopathologic features and prognosis of primary gastrointestinal stromal tumor (GIST).
Methods: The clinicopathologic and follow-up data of 314 patients with primary GIST treated in Xiangya Hospital of Central South University from January 2012 to August 2018 were retrospectively analyzed.
Results: Of the 314 GIST patients, 169 cases (53.8%) were males and 145 cases were (46.2%) females, with a median age of 55 (24-86) years and a median tumor diameter of 6 (1-34) cm; the primary site located in the stomach in 165 cases (52.6%), duodenum in 15 cases (4.8%), jejunum or ileum in 115 cases (36.6%), colorectum in 6 cases (1.9%), and other sites in 13 cases (4.1%). According to the modified NIH classification, the diseases of the patients were classified as very low risk in 11 cases (3.5%), low risk in 109 cases (34.7%), moderate risk in 80 cases (25.5%), and high risk in 114 cases (36.3%). All the 314 patients underwent surgical treatments, of whom, 305 cases (97.1%) achieved R0 resection, 4 cases (1.3%) received R1 resection, and 5 cases (1.6%) had R2 resection. Followed -up was obtained in 268 patients (85.4%) for a median time of 37 (2–69) months. Of the 194 patients with moderate or high risk disease, 67 cases (34.5%) received imatinib-based adjuvant therapy after operation, with a median time of 26 (7–56) months. In the whole group of patients, the 1-, 3- and 5-year relapse-free survival rates were 97.0%, 92.6% and 81.7%, and the 1-, 3- and 5-year overall survival rates were 99.4%, 95.2% and 88.2%, respectively. In patients with very low risk, low risk, moderate risk and high risk disease, the 5-year relapse-free survival rates were 100.0%, 93.3%, 79.1% and 64.4%, and the 5-year overall survival rates were 100.0%, 94.1%, 91.7% and 74.9%, respectively. Among the 194 patients with moderate or high risk disease, the 5-year relapse-free survival rates in the 67 cases with postoperative imatinib adjuvant therapy and the 127 cases without postoperative imatinib adjuvant therapy were 73.8% and 65.2%, and the 5-year overall survival rates were 87.5% and 71.6%, respectively.
Conclusion: Primary GIST is mostly found in the stomach and small intestine. Complete resection and imatinib-based adjuvant therapy based on risk classifications can lead to better prognosis. However, individualized treatment should be tailor to specific patients with high risk GIST, and close and regular follow-up is still needed in addition to the standard adjuvant therapy.