Waldenstrom macroglobulinemia is a type of non-Hodgkin lymphoma (NHL). The neoplastic cells make large amounts of an abnormal protein (called a macroglobulin). Another name for WM is lymphoplasmacytic lymphoma.
What is the Pathology of Waldenstrom Macroglobulinemia?
The pathology of Waldenstrom macroglobulinemia is:
-Etiology: The cause of Waldenstrom macroglobulinemia is not definitely known. Environmental familial, genetic, and viral factors have been reported.
-Genes involved: MYD88 gene
-Pathogenesis: The sequence of events that lead to Waldenstrom macroglobulinemia is preceded by an IgM monoclonal gammopathy of undetermined significance (MGUS) in most, perhaps all, patients.
-Histology: The histology associated with Waldenstrom macroglobulinemia shows the bone marrow containing variable numbers of pleomorphic lymphoid cells. Dutcher bodies may be seen as intracytoplasmic inclusions positive for periodic acid Schiff. Mast cell hyperplasia is common and may stimulate tumor cell proliferation and monoclonal IgM secretion. Blood smears show striking rouleau formation and occasional to frequent plasmacytoid lymphocytes which bear surface monoclonal IgM, usually κ, detected by flow cytometry.
Waldenstrom Macroglobulinemia. The tissue or bone marrow involvement pattern and immunophenotypic profiling of the EMWM and BMWM patients. a, b A representative diffuse interstitial pattern of bone marrow biopsy in a patient with BMWM, ×40 and × 80 magnification. c Bone marrow aspirate smear showed many abnormal small lymphoid cells admixed with variable plasmacytoid cells and plasma cells, ×80 magnification. d CD20 stain on the abnormal small lymphoid cells, ×80 magnification. e CD138 stain on the plasmacytoid and plasma cells, ×80 magnification. f, g Immunophenotypic profiling of CD38 and CD138 positive plasmacytoid and plasma cells with strong monotypic cytoplasmic kappa light chain expression. h The abnormal small lymphoid cells were CD20 positive and showed monotypic kappa light chain expression. i, j A representative diffuse infiltrative pattern of a lymph node biopsy in a patient with EMWM, MYD88 mutation positive, ×40 and × 80 magnification. k CD20 stain on abnormal small lymphoid cells, ×80 magnification. l CD138 stain on few admixed plasmacytoid and plasma cells, ×80 magnification. m, o Immunophenotypic profiling of CD19 and CD20 positive small B-cells with kappa light chain restriction and were negative for CD5 and CD10. p Identical monotypic kappa light chain expression in the lymphoid cells was also seen in the plasmacytoid and plasma cells. Waldenström macroglobulinemia with extramedullary involvement at initial diagnosis portends a poorer prognosis. Cao X, Ye Q, Orlowski RZ, Wang X, Loghavi S, Tu M, Thomas SK, Shan J, Li S, Qazilbash M, Yin CC, Weber D, Miranda RN, Xu-Monette ZY, Medeiros LJ, Young KH - Journal of hematology & oncology (2015). Not altered. No license or rights.
How does Waldenstrom Macroglobulinemia Present?
Patients with Waldenstrom macroglobulinemia are more often male than female, and present at a median age of 63 years old. The symptoms, features, and clinical findings associated with Waldenstrom macroglobulinemia include insidious weakness, and mucous membrane bleeding. Some patients may have infections, dyspnea, and congestive heart failure. Physical examination may detect pallor, purpura, lymphadenopathy, hepatosplenomegaly, and engorged retinal veins.
How is Waldenstrom Macroglobulinemia Diagnosed?
Waldenstrom macroglobulinemia is diagnosed by a blood test that shows an increase in IgM on protein electrophoresis associated with ≥10% clonal lymphoplasmacytic cells in bone marrow aspiration biopsy.
How is Waldenstrom Macroglobulinemia Treated?
Waldenstrom macroglobulinemia may be treated by combination therapy with rituximab and bendamustine.
What is the Prognosis of Waldenstrom Macroglobulinemia?
The prognosis of Waldenstrom macroglobulinemia is good. The five-year survival rate of Waldenstrom’s macroglobulinemia is about 80 percent. Recent studies suggest that the median survival rates are 16 years after diagnosis. This, plus the fact that people with Waldenstrom macroglobulinemia tend to be older when diagnosed, puts their survival rates closer to those expected for the general population.
