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, platelet count, haemoglobin concentrations, β2-microglobulin and monoclonal component concentration. Serum albumin and lactate dehydrogénase (LDH) levels also retain a prognostic role and these two characteristics have been incorporated in a proposal for a revision of this index. Improving prognostic assessment at the time of the first treatment initiation and taking into account the prognostic impact of events occurring in the course of evolution, should improve the strength of treatment decision at the time of initial treatment and during the follow-up. It should also help to design clinical trial for fast and effective evaluation of new treatments. Our work should also help to adjust clinical monitoring of asymptomatic patients. Prospective and retrospective multicenter prognostic study with a descriptive objective, associated with a biological collection appropriately annotated and stored. A retrospective series including 470 patients with symptomatic WM is already available. The follow-up of these patients will be updated and an additional series of 250 symptomatic patients will be prospectively enrolled. 250 asymptomatic patients will be also enrolled.