The Therapy of Hairy Cell Leukemia: The State of Art

Hairy cell leukemia is a B-cell chronic lymphoproliferative disorder in which in the last 3 decades has been registered tremendous progress both in the development of effective treatments capable to improve complete remission rates, as well as in elucidating new biologic and molecular aspects of the leukemic hairy cells. a-IFN was the first effective therapeutic approach in HCL capable of improving the clinical course of the disease. However, only after introduction of purine analogs (Pentostatin and Cladribine), a significant improvement in the number and duration of CR has been observed. Beside purine analogs agents who still represent the cornerstone of HCL treatment, the addition of anti-CD20 monoclonal antibody (Rituximab) and/or anti-CD22 (BL22) immunotoxins, represent the best way to rescue patients who failed prior treatments with a-IFN or purine analogs. Finally, new emerging drugs as Vemurafenib (BRAFV600E mutation inhibitor) and Ibrutinib, are under investigation with success in resistant and/or relapsed patients.