Waldenström's macroglobulinemia.

Waldenström's macroglobulinemia is a low-grade lymphoplasmacytic lymphoma. It has an overall incidence of 2.5/million/year. The median age at diagnosis is 63 years. The clinical manifestations are hepatomegaly (20%), splenomegaly (15%), and lymphadenopathy (15%). The most common symptom is fatigue related to a normochromic, normocytic anemia, and the median hemoglobin value at diagnosis is 10 gm/dl. All patients with Waldenström's macroglobulinemia have a circulating tumor marker, the monoclonal IgM protein. Occasionally high levels of the IgM monoclonal protein can produce a hyperviscosity syndrome manifested by oronasal bleeding. Occasionally retinal hemorrhage or serious neurologic complications, such as somnolence or coma, may occur. The most important prognostic factors are hemoglobin, age, weight loss, and a cryoglobulin. Therapy has included alkylating agents, particularly chlorambucil, purine nucleoside analogs such as fludarabine or cladribine, and most recently the use of rituximab. The median survival of symptomatic patients is 65 months. Patients without symptoms should not be treated.