We herein report the first case in which an escalated dose of sunitinib was effective, even after dose reduction. A 64-year-old man with gastrointestinal stromal tumor of the small intestine discontinued adjuvant imatinib because of interstitial pneumonia. After two years, peritoneal recurrence was detected. Sunitinib was started at 50 mg/day for 4 weeks every 6 weeks, after which the dosage was reduced to 37.5 mg/day because of grade 1 gastritis, stomatitis, and a fever. Four months later, computed tomography showed progressive disease. As the adverse events were well-controlled by medication, we escalated the dose to 50 mg/day and achieved a partial response.
Keywords: dose modification; gastrointestinal stromal tumor; sunitinib.