Waldenstrom macroglobulinaemia involving extramedullary sites

Waldenstrom macroglobulinaemia is a B-cell neoplasm associated with a monoclonal IgM gammopathy.

The bone marrow is almost always involved. There is hepatomegaly, lymphadenopathy or splenomegaly in 15-20% of patients. Hyperviscocity syndrome occurs in 15-20% of patients.

Histopathology and Immunohistochemistry of extramedullary sites

Where there are extramedullary tumour deposits, these vary in moth morphology and immunophenotype. In a study of 44 patients with extramedullary disease, the following were reported¹:

• Low grade lymphoplasmacytic lymphoma, CD5-: nodal = 28, extranodal = 11. Lymphoplasmacytic (many plasmacytoid lymphocytes and more mature plasma cells) = 21, lymphoplasmacytoid (mainly small mature lymphocytes with a variable number of plamacytoid lymphocytes and rare plasma cells) = 18. Six cases had marked interfollicular infiltration, reactive germinal centres and monocytoid B-cells resembling MZBCL. One showed nodular expansion of follicles, simulating follicular lymphoma. One contained numerous epithelioid histiocytes, simulating LPHD.

• Aggressive lymphoma associated with concurrent lymphoplasmacytic lymphoma in the bone marrow: nodal = 4, extranodal = 2. DLBCL = 4, polymorphous lymphoplasmacytic lymphoma = 1, composite classical HD = 1.

• Variant lymphoplasmacytic lymphoma, CD5+: nodal = 1, extranodal = 1. In one case the bone marrow infiltrate was also CD5+. In the other, the bone marrow infiltrate was CD5-.

• Other non-Hodgkin lymphomas: nodal = 3, extranodal = 1. SLL/CLL = 2, MCL (cyclin D1+, t(11;14)) = 1, cutaneous FL (bcl-6+) = 1.

Others have reported Waldenstrom macroglobulinaemia in association with MZBCL^2,3,4,5, SMZL⁶,

References

¹Lin, P., C. Bueso-Ramos, et al. (2003). "Waldenstrom macroglobulinemia involving extramedullary sites: morphologic and immunophenotypic findings in 44 patients." Am J Surg Pathol 27(8): 1104-13.

²Allez, M., X. Mariette, et al. (1999). "Low-grade MALT lymphoma mimicking Waldenstrom's macroglobulinemia." Leukemia 13(3): 484-5.

³Berger, F., P. Felman, et al. (2000). "Non-MALT marginal zone B-cell lymphomas: a description of clinical presentation and outcome in 124 patients." Blood 95(6): 1950-6.

⁴Nakata, M., Y. Matsuno, et al. (1997). "B-cell lymphoma accompanying monoclonal macroglobulinemia with features suggesting marginal zone B-cell lymphoma." Int J Hematol 65(4): 405-11.

⁵Valdez, R., W. G. Finn, et al. (2001). "Waldenstrom macroglobulinemia caused by extranodal marginal zone B-cell lymphoma: a report of six cases." Am J Clin Pathol 116(5): 683-90.

⁶Van Huyen, J. P., T. Molina, et al. (2000). "Splenic marginal zone lymphoma with or without plasmacytic differentiation." Am J Surg Pathol 24(12): 1581-92.

This page last revised 11.9.2003.

©SMUHT/PW Bishop