The efficacy and prognostic factors of imatinib mesylate in treatment of advanced gastrointestinal stromal tumors

Objective: To study the efficacy and prognostic factors of oral imatinib mesylate in the treatment of patients with GIST (advanced gastrointestinal stromal tumor). Methods: One hundred and two patients with recurrent and /or metastatic GIST received oral imatinib mesylate (the initial dose was 400 mg daily, and this dose was increased to 600 mg daily for those who had progression disease). Results: Ninety-nine patients were evaluable for the response. Of these 99 patients, 8 patients (8.1%) achieved complete response, 68 patients (68.7%) achieved partial response, 20 patients (20.2%) had stable disease, and 3 patients (3.0%) had progression disease. The objective response rate (complete response＋ partial response) was 76.8%. The median progression-free survival was 32.0 months; the 1-, 2-, 3-year survival rates were 96.1%, 81.2% and 70.8%, respectively. The factors of urban living, ECOG (Eastern Cooperative Oncology Group) performance status score ＜2 and having an objective response were significantly associated with the better progression-free survival (P＜0.05), while the factors of younger patients, urban living, ECOG performance status score ＜2, liver metastasis alone and the decrease in tumor density were significantly associated with the better overall survival (P＜0.05). Conclusion: Oral imatinib mesylate is effective and safe in the treatment for patients with advanced GIST. The age, baseline PS score, short-term response and the change of tumor density by CT scan were important prognostic factors for advanced GIST. DOI:10.3781/j.issn.1000-7431.2011.07.013