Surgical management of advanced gastrointestinal stromal tumors: an international multi-institutional analysis of 158 patients.

BACKGROUND Patients with advanced gastrointestinal stromal tumors (GIST) are at high risk for recurrence after surgery. The aim of this study was to characterize outcomes of advanced GIST treated with surgery from a large multi-institutional database in the tyrosine kinase inhibitor (TKI) era. STUDY DESIGN Patients who underwent surgery for an advanced GIST from 1998 through 2012 were identified. Demographic, clinicopathologic, perioperative, and survival data were collected and analyzed. RESULTS There were 87 patients with locally advanced GIST and 71 patients with recurrent/metastatic GIST. The vast majority (95%) of patients with locally advanced GIST required a multivisceral resection; most patients (87%) underwent a microscopically complete (R0) resection. Although 82% of patients had high-risk tumors according to modified NIH criteria or had recurrent/metastatic disease, only 56% of patients received adjuvant TKI therapy. Among patients with locally advanced GIST, 3-year recurrence-free survival and overall survival rates were 65% and 87%, respectively. In contrast, 3-year recurrence-free survival and overall survival rates among patients with recurrent/metastatic GIST were 49% and 82%, respectively. On multivariate analysis, predictors of worse outcomes included high mitotic rate and male sex for patients with locally advanced GIST, and age and lack of adjuvant TKI therapy were associated with adverse outcomes among patients with recurrent/metastatic GIST (all p < 0.05). CONCLUSIONS Resection of advanced GIST can be safely accomplished with high rates of R0 resection. Among patients with advanced GIST, TKI therapy was underused. Barriers to the use of TKI therapy in this population should be explored.