Diagnosis And Treatment Of Gastric Stromal Tumors: A Report Of 61 Cases

Gastrointestinal stromal tumor (GIST) is the most commonmesenchymal malignancy of the gastrointestinal tract. This tumor is resistant to conventional chemotherapy and radiotherapy. Although surgery has been the only effective treatment for GIST to date, it is not enough to manage metastatic GIST. Imatinib mesylate, a KIT tyrosine kinase inhibitor, is an oral agent that has been found to have a dramatic antitumor effect on metastatic GIST. Although imatinib mesylate has been used in GIST treatment for several years, its use marks a new era of molecular targeting therapy. While several issues remain,they should be clarified by the current clinicaltrials and associated laboratory studies.Objective To explore the diagnosis and treatment of gastric stromal tumors (GSTs). Methods The Clinical and pathological data including immunohistochemical results of 61 patients with GSTs from 1998 to 2005 were collected, and The Clinical and pathological data were analyzed retrospectively. The relationship of various clinicopathologic characteristics and outcomes were tested by univariate analysis. Results Wedge resection were performed on 30 patients, partial gastrectomies on 24 patient and total gastrectomies on 7 patients. According to the Fletcher classification, 7 patients were of very low risk (11%) ,26 of low risk (43%) , 19 of intermediate risk (31%), and 9 of high risk(15 %). CD117 staining was positive in 93% cases, and CD34 was in 83%. The time of median follow-up was 28 months(2months-91 months). The patient 5-year survival rates were 83%, 5-year tumor-free survival rates were 72%. 12 patients got recurrence or metastasis: 3 patients got local recurrence and 9 patients got distant metastasis which included liver (6 patients), peritoneum (3 patients). The time from surgery to recurrence or metastasis was 3-36 months and 6patients died at last, univariate analysis showed Fletcher classification, tumors with necrosis ,bleeding were associated with prognosis(P<0.05) . Conclusions surgery is still the maine treatment for GSTs, tumors with necrosis ,bleeding and high risk in Fletcher' types are poor prognosis factors.