Different sites and prognoses of gastrointestinal stromal tumors of the stomach: report of 187 cases.

Background: The stomach is the most common site of gastrointestinal stromal tumors (GISTs), but the clinical behavior of gastric GISTs at different sites is unclear. This study was designed to evaluate the clinicopathological (CP) parameters and influence of different gastric sites on outcome in patients with GIST.

Methods: The CP and follow-up records of 187 patients with GIST who were treated at TianJin Medical University Cancer Institute & Hospital between January 1985 and December 2006 were reviewed. There were 97 men and 90 women (aged 17-88 (median, 56.5) years). CP factors were assessed for overall survival (OS) by using univariate and multivariate analysis.

Results: The numbers of cases of upper, middle, and lower third gastric GISTs were 69 (36.9%), 103 (55.1%), and 15 (8%), respectively. Sites of GISTs in the middle or upper stomach, tumor size, intermediate- or high-risk groups, high mitotic count, and low resection status were associated with poor OS (p = 0.041, 0.046, 0.006, 0.000, 0.000, respectively) in a univariate analysis. In a multivariate analysis, tumor location in the upper and middle third of the stomach (p = 0.035), an intermediate or high risk (p = 0.01), and incomplete resection status (p = 0.006) were predictive of poor OS.

Conclusions: Patients in intermediate- and high-risk groups had an unfavorable outcome. A complete resection is the most important treatment for survival. The location of GIST in the lower third of the stomach may be a favorable factor, and the significance of different tumor sites for prognosis of gastric GISTs needs to be further clarified.