Imatinib Desensitization After a Type IV Hypersensitivity Reaction in a Gastrointestinal Stromal Tumor Patient—A Case Report

Background: Imatinib treatment is approved for several indications, including chronic myeloid leukemia (CML) and gastrointestinal stromal tumors (GIST). Although adverse events are common, hypersensitivity reactions are not. Because there is a clear clinical benefit of imatinib treatment, re-introduction of imatinib after a hypersensitivity reaction should be considered. Case: Here we present a case report of a 68-year-old patient with a GIST diagnosis who was re-introduced to imatinib after a type IV hypersensitivity reaction via desensitization. A desensitization plan, a plan for formulation of low-dose imatinib capsules, and the essential steps when considering desensitization are discussed. Conclusion: Our case of a patient with a type IV hypersensitivity reaction after starting imatinib treatment demonstrates that desensitization is a feasible option after serious cutaneous adverse events in specific cases, when done with good interdisciplinary collaboration and clinical management.