Prognostic Analyses on a Validation Series of Patients With Waldenström's Disease

Waldenström's macroglobulinemia (WM) is defined by the association of bone marrow lymphoplasmocytic infiltration and monoclonal immunoglobulin M (IgM). A mutation in the MYD88 gene is found in up to 90% of patients, and a mutation in the CXCR4 gene in approximately one third of patients. Treatment should be initiated in cases of cytopenia, bulky disease or when the physicochemical or immunological properties of IgM explain the occurrence of amyloidosis, cryoglobulin, neurological manifestations, or hyperviscosity syndrome (due to the presence of a large amount of IgM). However, approximately 30% of patients are diagnosed without any symptom and therefore they do not meet the criteria for initiating treatment. At the time of initiation of the first treatment, the prognosis is usually estimated with the International Prognostic Index (IPSSWM) which is based on five variables: age, platele