Dendritic cell-mediated immunization in macroglobulinemia

Diagnosis and management of Waldenstrom's macroglobulinemia

PURPOSE

To review the diagnostic criteria, prognostic factors, response criteria, and treatment options of patients with Waldenstrom's macroglobulinemia (WM).

METHODS

A review of published reports was facilitated by the use of a MEDLINE computer search and by manual search of the Index Medicus.

RESULTS

WM should be regarded as a distinct clinicopathologic entity and confined to those patients with lymphoplasmacytoid lymphoma who have demonstrable serum immunoglobulin M monoclonal protein. Treatment decisions should rely on specific clinical and laboratory criteria. Initiation of therapy should not be based on serum monoclonal protein levels per se. The three main choices for systemic primary treatment of symptomatic patients with WM include alkylating agents (chlorambucil), nucleoside analogs (fludarabine and cladribine), and the monoclonal antibody rituximab. There are no data from prospective randomized studies to recommend the use of one first-line agent over another, although consideration of a patient's candidacy for autologous stem-cell transplantation (ASCT) should be taken into account to avoid stem cell-damaging agents. There are preliminary data to suggest that combinations of nucleoside analogs and alkylating agents with or without rituximab may improve response rates at the expense of higher toxicity.

CONCLUSION

WM is a distinct low-grade lymphoproliferative disorder. When therapy is indicated, alkylating agents, nucleoside analogs, and rituximab are reasonable choices. Several factors, including the presence of cytopenias, need for rapid disease control, candidacy for ASCT, age, and comorbidities, should be taken into consideration when choosing the most appropriate primary treatment.

Treatment Options in Waldenstrom's Macroglobulinemia

Waldenstrom's macroglobulinemia (WM) is a rare chronic B-cell lymphoproliferative disorder characterized by macroglobulin (immunoglobulin M; IgM) paraproteinemia. The clinical manifestations associated with WM can be related to those of direct organ tumor infiltration, hyperviscosity and tissue deposition of IgM. Treatment must be individualized according to the nature of the clinical manifestations. Plasmapheresis has a role in patients whose symptoms are caused by increased serum viscosity. Chlorambucil was first used with response rates varying between 31% and 72% and is now probably the most commonly used oral agent. Melphalan and cyclophosphamide may have similar clinical efficacy. The addition of corticosteroids does not seem to increase response rates and the use of combination chemotherapy in the first-line setting is not recommended. Fludarabine and cladribine are cross-resistant and induce a response in 30%-60% of patients who have had prior therapy with alkylating agents and as many as 100% of previously untreated patients. Thirty-five percent to 50% of patients respond to single rituximab therapy, with limited toxicity. There are no data from prospective randomized studies to guide the choice between alkylating agents, nucleoside analogues, and rituximab for first-line therapy of WM. Autologous and allogeneic stem cell transplantation may be considered for patients with primary refractory/relapsing disease, especially in the younger age groups. Thalidomide alone or in combination with steroids/clarithromycin may be a useful salvage regimen for some heavily pretreated patients with cytopenia, even though toxicity is considerable. Splenectomy is rarely indicated.