[A case of small intestinal GIST maintained as a long stable disease by imatinib mesylate 400 mg/day, alternate-day administration for 2 weeks followed by a 2 week interval].

UNLABELLED: Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the gastrointestinal tract. The recent molecular-targeted therapies (imatinib and sunitinib) have improved the treatment of GIST remarkably. However, it would be ideal if the amount of these drugs could be adjusted according to each patient because they have various side effects and are very expensive. We experienced a case of non-curative resectable GIST maintained as a long, stable disease after operation, despite tapering down the dose of imatinib mesylate for personal reasons. CASE: A woman aged 50. She had received surgery for a lower abdominal tumor, and had been diagnosed with GIST of the small intestine and disseminations. When she suspended taking imatinib (400 mg/day) after her operation, these tumors regrew. After restarting imatinib at 400 mg/day in an alternate-day administration lasting 2 weeks followed by a 2 week interval, the disseminated tumors were in significant for 60 months after the operation.