Diagnostic criteria for Waldenström macroglobulinemia
| IgM monoclonal gammopathy of any concentration |
| Bone marrow infiltration by small lymphocytes showing plasmacytoid or plasma cell differentiation |
| Intertrabecular pattern of bone marrow infiltration |
| Surface IgM+ CD5±CD10−CD19+CD20+CD22+CD23−CD25+CD27+FMC7+CD103−CD138− immunophenotype* |
| IgM monoclonal gammopathy of any concentration |
| Bone marrow infiltration by small lymphocytes showing plasmacytoid or plasma cell differentiation |
| Intertrabecular pattern of bone marrow infiltration |
| Surface IgM+ CD5±CD10−CD19+CD20+CD22+CD23−CD25+CD27+FMC7+CD103−CD138− immunophenotype* |
From Owen et al.7 Used with permission.
Ig indicates immunoglobulin.
Variations from this phenotypic profile can occur, and care must be taken to satisfactorily exclude other lymphoproliferative disorders. This is particularly relevant in those that express CD5.