Successful Rechallenge with Imatinib in a Patient with Chronic Myeloid Leukemia Who Previously Experienced Imatinib Mesylate Induced Pneumonitis

Imatinib mesylate is a targeted therapy that acts by inhibiting tyrosine kinase of the bcr-abl fusion oncoprotein, which is specific to chronic myeloid leukemia (CML), and the c-transmembrane receptor, which is specific to gastrointestinal stromal tumors. Interstitial pneumonitis is a rare adverse event of imatinib therapy. It is clinically difficult to distinguish from infectious pneumonia, which can frequently occur due to the underlying disease. The standard treatment for imatinib-induced pneumonitis is to discontinue the medication and optionally administer corticosteroids. However, there are a few cases of successful retrial with imatinib. We describe a case of successful rechallenge of imatinib in a patient with imatinib-induced interstitial pneumonitis and CML without a recurrence of the underlying disease after 3 months of follow-up.