Lymphoplasmacytic lymphoma/Waldenstrِm macroglobulinemia with inv(16)(p13q22) as a sole genetic abnormality

Inversion of chromosome 16, inv(16)(p13q22), juxtaposes the core binding factor beta (CBFB) and myosin heavy chain 11 (MYH11) genes, resulting in a myeloid leukemic disease phenotype characterized by increased bone marrow and peripheral blood blasts with myelomonocytic antigen expression and an accompanying eosinophilia. This cytogenetic abnormality has been reported in a variety of other neoplasms, in which it generally occurs as part of a complex karyotype, including rare B-lineage non-Hodgkin lymphomas. We report a case of clinically, morphologically, and immunologically typical lymphoplasmacytic lymphoma/Waldenstrِm macroglobulinemia in which a majority of the malignant cells had an inv(16)(p13q22) as a sole abnormality. We review the literature and discuss the possible role of this genetic lesion in B-cell neoplasia.