A Case of Lymphoplasmacytic Lymphoma/Waldenström's Macroglobulinemia with IgM-κ and IgA-λ Biclonal Gammopathy

Lymphoplasmacytic lymphoma (LPL) is a low-grade B-cell neoplasm, composed of small B lymphocytes, plasmacytoid lymphocytes, and plasma cells, usually involving bone marrow and sometimes lymph nodes or spleen. LPL with bone marrow involvement and an IgM monoclonal gammopathy of any concentration is designated as Waldenström macroglobulinemia (WM). LPL associated with non-IgM monoclonal gammopathy or biclonal gammopathy is rarely observed. LPL diagnosis was based on clinical, morphological, and immunophenotypic findings. Recently, the test for L265P mutation of the myeloid differentiation factor 88 (MYD88) gene has been helpful in the diagnosis of LPL. Here, we reported the first case of LPL/WM with IgM-κ/IgA-λ biclonal gammopathy in Korea.