BRAF Mutations in Hairy-Cell Leukemia

In this study, investigators identified activating mutations in BRAF (specifically V600E, which is also present in some melanomas and thyroid cancers) in all 48 patients with hairy-cell leukemia who were evaluated. Hairy-cell leukemia (HCL) is a distinct disease entity that is characterized by an indolent course, marked splenomegaly, progressive pancytopenia in many cases, and rare circulating tumor cells, usually with no lymphadenopathy. 1 The bone marrow, spleen, and liver are characteristically infiltrated by leukemic B cells that have abundant cytoplasm with hairy-looking projections and unique immunophenotypic features. 2 , 3 Currently, the treatment of HCL is based on highly effective purine nucleoside analogues. 4 In spite of the remarkable progress in the diagnosis and treatment of HCL during the past 50 years, the underlying genetic alterations that cause the disease remain obscure. 3 Major obstacles to . . .