Rationale: Imatinib mesylate (imatinib) is a classic tyrosine kinase inhibitor used to treat chronic myeloid leukemia. Although it is well tolerated by most patients and helps in the achievement of complete remission, a few rare imatinib-associated adverse effects such as pulmonary interstitial fibrosis have been reported. Because of its rareity, the clinical features of imatinib-induced interstitial lung disease (ILD) remain unclear.
Patient concerns: A 49-year-old Chinese man with chronic myeloid leukemia received oral treatment with imatinib and initially exhibited a good response. However, he presented with cough and fever 9 months after treatment initiation.
Diagnoses: Pulmonary computed tomography indicated diffuse interstitial fibrosis in both lungs. All tests for possible infectious pathologies provided negative results.
Interventions: The patient was diagnosed with interstitial pneumonia and treated with antibiotics; however, there was no improvement. On the basis of a suspicion of imatinib-induced ILD, imatinib was discontinued and prednisone treatment was initiated.
Outcomes: The patient's symptoms ameliorated with treatment, and imatinib was reintroduced. However, he developed cough and dyspnea again, and his treatment was switched to nilotinib as a second-line regimen. He was regularly monitored, and although his clinical symptoms ameliorated, computed tomography performed 29 months after he was diagnosed with ILD showed irreversible pulmonary interstitial fibrosis without progression.
Lessons: Clinicians should consider the possibility of severe irreversible ILD and carefully monitor patients receiving imatinib treatment.