B-cell prolymphocytic leukemia

A rare mature B-cell neoplasm characterized by clonal proliferation of B-cell prolymphocytes, with prolymphocytes constituting more than 55% of lymphoid cells in peripheral blood. IG genes are clonally rearranged. Neoplastic cells are present in the bone marrow, peripheral blood, and spleen. Patients usually present with B symptoms, massive splenomegaly but absent or minimal lymphadenopathy, rapidly increasing lymphocyte count, anemia, and thrombocytopenia. Therapy response is poor.