Image Description
Lymph node involvement in HCL is uncommon and may be seen after splenectomy or in long-standing cases. Abdominal and retroperitoneal lymph nodes are the ones usually affected. The hairy cells are distributed in a paracortical fashion and surround the germinal centers. The appearance may mimic marginal zone lymphoma.
About the Disease
Hairy Cell Leukemia (HCL) is a mature B-cell neoplasm that mainly involves the blood, bone marrow, and splenic red pulp. It makes up only about 2% of all leukemias and predominantly affects middle-aged men (M:F = 4:1).The clinical features are often related to cytopenias and include recurrent infections (due to neutropenia) and weakness and fatigue (due to anemia). Monocytopenia is one of most sensitive markers of HCL. Splenomegaly is seen in 80% to 90% of cases; lymphadenopathy is uncommon. A small proportion of patients show polyclonal hypergammaglobulinemia. In about one-fourth of the patients, HCL is diagnosed incidentally.The neoplastic lymphocytes have an ill-defined, ruffled cytoplasmic border with hair-like surface projections. They express B-cell associated antigens CD19, CD20, and CD22. In addition, they are positive for CD103, CD25, and CD11c.