Management of imatinib-associated skin rash in a patient with metastatic gastrointestinal stromal tumor: a case report

We report a 56-year-old man with metastatic KIT+ GIST of the liver who had Grade 3 imatinib intolerance (skin rash) when treatment was started. The rash was managed with antihistamine treatment (Dexchlorpheniramine maleate 4 mg per day) and several temporary (up to 2 weeks) dose interruptions. The patient’s skin rash partially improved, and he tolerated gradual reintroduction of imatinib over several months. The patient maintained imatinib 400 mg/d, and tolerated it during the 2 years when he was on antihistamine treatment. After 2 years, the patient continued imatinib therapy without having to take antihistamines. The patient responded according to RECIST 1.1 and Choi to imatinib treatment for his metastatic GIST (partial response). As of September, 2012, the patient has been on imatinib therapy for 131 months and remains progression free.The results of this case report demonstrated that a patient with metastatic KIT+ GIST who was initially intolerant to imatinib maintained, and responded to imatinib therapy after treatment of an imatinib-associated adverse effect. These results suggest that initial intolerance to imatinib should not necessarily result in treatment discontinuation, as these adverse effects, when managed properly, may be tolerated and may decrease over time.Imatinib mesylate is approved for the treatment of adult patients with unresectable and/or metastatic KIT+ gastrointestinal stromal tumor (GIST) and for the adjuvant treatment of adult patients following resection of primary GIST [1]. Current treatment guidelines recommend long-term continuous imatinib therapy in patients with advanced GIST and at least 12 months of adjuvant imatinib therapy for patients with a substantial risk of relapse [2,3]. Recently reported results of the Scandinavian Sarcoma Group/Sarcoma Group of the Arbeitsgemeinschaft Internistische Onkologie (SSGXVIII/AIO) trial indicate that at least 3 years of adjuvant imatinib should be recommended in patients who have a considerabl