A rare B-cell non-Hodgkin lymphoma characterised by the presence of small B-lymphocytes, plasmacytoid lymphocytes and plasma cells, and either non-secreting or secreting IgG or IgA paraproteins. The disease usually involves the bone marrow and sometimes also the spleen or lymph nodes. Patients typically present with symptoms related to anaemia. Hyperviscosity, autoimmune phenomena and B symptoms may also be observed. Mortality is higher as compared to Waldenström macroglobulinaemia. [from
SNOMEDCT_US]