Optimized dose of imatinib for treatment of gastrointestinal stromal tumors: a meta-analysis.

OBJECTIVE: To investigate the efficacy and safety of standard-dose versus high-dose imatinib. METHODS: After a systematic review of English language articles, five studies including 2008 patients were eligible for the meta-analysis. Data extracted from each study were synthesized into overall odds ratios (OR). RESULTS: The overall OR for the high dose vs standard dose was 1.19 (95% CI 1.00-1.42) and the Z-score for the overall effect was 1.93 (P = 0.054), suggesting that high-dose imatinib added no survival benefits. The dose-related toxicity was also assessed in the same way. The rates of rash, hemorrhage, nausea, vomiting and taste disturbance increased as dose increased (P < 0.05), whereas the incidence of headache, abdominal pain, edema, fatigue, anemia, infection, muscle cramp and constipation was nearly identical and showed no significant difference. CONCLUSIONS: Imatinib at a standard dose produces a similar effect to that at a high dose. The severity of the toxicity is associated with the dose of imatinib. However, larger and randomized studies are needed to draw definitive conclusions.