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

Go, Seong Woo; Kim, Boo Kyeong; Lee, Sung Hak; Kim, Tae-Jung; Huh, Joo Yeon; Lee, Jong Min; Hah, Jick Hwan; Kim, Dong Whi; Cho, Min Jung; Kim, Tae Wan; Kang, Ji Young

The standard treatment is to stop the drug, observe the course of the disease, and optionally administer steroids 5 . Although the prognoses are diverse, mostly the disease is mild and resolves promptly with treatment 5 . It can rarely cause fatal or irreversible results such as respiratory failure or permanent structural distortion of the lung 10 . In addition, the prognosis might be poor if a patient has a history of lung disease. Some other options for managing the underlying disease of patients with imatinib-induced pneumonitis have been reported. Ohnishi et al. 2 found that 23 of 27 patients with imatinib-induced interstitial pneumonitis recovered with corticosteroid treatment and discontinuation of the drug. They reported that four of 11 patients who were readministered 100-400 mg imatinib daily relapsed with interstitial pneumonitis. Delomas et al. 11 reported a case of a patient with CML with pneumonitis who did not relapse after switching to nilotinb. Three cases of imatinib-induced interstitial pneumonia have been reported in Korea; two CML and one patient with GIST 3,4 . The patient with CML stopped imatinib treatment and took steroid therapy, but died. The other patient with CML recovered with steroid therapy, changed from imatinib to nilotinib, and survived. The other patient with GIST improved by discontinuing the imatinib and commencing steroid therapy. The present case is the first domestic report of successful imatinib rechallenge in a patient with CML after recovery from interstitial pneumonitis without recurrence at a 3 month follow-up. However, symptoms and chest radiographs should be monitored because a pneumonitis relapse can occur during readministration of the drug. In addition, further studies about duration of discontinuing imatinib and starting steroid therapy, optimal timing for imatinib rechallenge, and the superiority between an imatinib retrial or switching to another drug are required.