Long-term follow-up of interferon-alpha induction and low-dose maintenance therapy in hairy cell leukemia
Interferon-α (IFNα) was the first effective pharmacologic treatment of hairy cell leukemia (HCL). Since 1990 purine analogs replaced IFNα because of higher rates of complete remission and an invariable disease recurrence after cessation of IFNα. However, there are only limited data about long-term maintenance treatment with IFNα and none about dose finding in this phase. Patients and methods:
Fifty-two consecutive patients treated at our institution for HCL are included in this retrospective analysis. Forty (77%) patients received IFNα and 35 patients continue on long-term IFNα maintenance therapy. The initial dose of IFNα was 3 Mio IU three times per week and was tapered 6 months after initiation to doses as low as 3 Mio IU/12 wk. Dose adaptation was performed by repeated measurement of soluble Interleukin 2 receptor (sIL2R) together with peripheral blood values. Results:
The median follow-up of patients in the long-term IFNα group was 13.6 ± 7.5 yr. Long-term IFNα was in general well tolerated and only in six (17%) patients the treatment had to be changed to purine analogs in the long-term IFNα group because of side effects. There are no deaths directly related to HCL. Conclusions:
IFNα is still an effective and well tolerated therapeutic option. By repeated measurements of sIL2R together with the peripheral blood values, IFNα doses can be tapered to the minimal effective dose. The advantages and disadvantage of IFNα in regards to the standard treatment in HCL patients are discussed.
Document Type: Research Article
Affiliations: 1: Clinic for Haematology and Oncology, Department of Internal Medicine, Kantonsspital Münsterlingen, Switzerland 2: Clinic for Haematology and Oncology, Stadtspital Triemli, Zürich, Switzerland 3: Clinic for Haematology, Department of Internal Medicine, University Hospital Zürich, Switzerland
Publication date: March 1, 2009