The Therapy of Hairy Cell Leukemia: The State of Art

Review Article

Ann Hematol Oncol. 2015;2(4): 1035.

The Therapy of Hairy Cell Leukemia: The State of Art

Lauria AF Gozzetti* and Raspadori D

Department of Hematology, University of Siena, Italy

*Corresponding author: Franceso Lauria, Sezione di Ematologia e Trapianti, Dipartimento di Medicina Clinica e Scienze Immunologiche, Università di Siena & AOUS, Siena, Italy

Received: March 25, 2015; Accepted: May 01, 2015; Published: May 08, 2015

Abstract

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.

Introduction

What is Hairy Cell Leukemia (HCL)

First described by Bouroncle et al. [1] as leukemic Reticuloendotelios is, HCL is a well-recognized chronic lymphoproliferative disorder frequently associated with anemia, thrombocytopenia, granulocytopenia, monocytopenia, bone marrow fibrosis and splenomegaly. It is characterized by the proliferation of large lymphocytes arising from a post-germinal mature B cell (activated B cell) which present typical cytoplasmic projections ( Hairy cells) involving peripheral blood, bone marrow, spleen, liver and, very infrequently, lymphnodes. Common clinical characteristics include fatigue, fever, infections, abdominal discomfort and easy bruising.

HCL is considered a very rare disease accounting for the 2% of all types of leukemia’s (500-600 cases every year) and is particularly prevalent in males (male: female ratio 5:1) with a median age at diagnosis of 56 years.

Diagnosis

HCL should be suspected in patients with variable degree of pancytopenia, absolute monocytopenia, and on the recognition, on the peripheral blood smears, of the circulating Hairy cells (HC) and, possibly, by the presence of spleen enlargement (Figure 1). After that, diagnosis should be confirmed by:

Citation: Gozzetti LAF and Raspadori D. The Therapy of Hairy Cell Leukemia: The State of Art. Ann Hematol Oncol. 2015;2(4): 1035. ISSN:2375-7965