Effect of Imatinib (STI571) on Metastatic Gastrointestinal Stromal Tumors: Report of a Case

The prognosis for advanced gastrointestinal stromal tumor (GIST) is poor. However, recent reports from Europe have described the effects of imatinib against metastatic GIST. We herein report the case of a Japanese patient treated with imatinib for advanced GIST. Imatinib at 400mg daily was given to an adult with multiple liver and peritoneal metastases 17 months after undergoing a GIST resection. The sum of the diameter of all target lesions decreased from 37.7 to 10.9cm at 6 months. Tinnitus (grade 2), which has not been reported elsewhere as an adverse effect, developed at 2 months. However, it did not require any treatment. Other adverse effects, nausea (grade 2) and anemia (grade 2), resolved spontaneously. Our results are consistent with previous reports that show imatinib to be effective for the treatment of metastatic GIST, and also suggest that imatinib at 400mg daily for more than 7 months is well tolerated in Japanese adults.