[Treatment-free molecular remission achieved by combination therapy with imatinib and IFNα in CML with BIM deletion polymorphism relapsed after stop imatinib].

A 51-year-old man with chronic myeloid leukemia (CML) was treated with imatinib (IM). After 24 months of treatment, he achieved a complete molecular response (CMR), which he sustained for 3 years. However, 4 months after discontinuing IM treatment, the CML relapsed. The patient was treated again with IM and achieved CMR. A combination of IM and interferon-α (IFNα) was administered for the following year, and then discontinued. The patient has since sustained CMR without therapy for 24 months, to date. This patient was found to have a BCL2L11 (BIM) deletion polymorphism. CML patients with a BIM deletion polymorphism show a low response to IM, and we infer that the BIM deletion polymorphism is a negative factor for discontinuation of IM. IFNα treatment is expected to prevent relapse during immunological surveillance. Therefore, the combination of IM and IFNα might be a feasible approach for CML patients who experience difficulty with IM discontinuation.