WALDENSTROMS MACROGLOBULINEMIA - INCIDENCE PATTERNS IN THE UNITED-STATES, 1988-1994

BACKGROUND. There are few data describing the epidemiologic aspects of Waldenstrom's macroglobulinemia (WM), a rare lymphoplasmaproliferativ e disorder. METHODS. The authors evaluated the incidence of WM reporte d in 11 population-based cancer registries in the U.S. RESULTS. A tota l of 624 cases were diagnosed between January 1, 1988 (when WM became reportable) and December 31, 1994. Age-adjusted incidence rates for WM (per 1 million person-years at risk) were 3.4 among males and 1.7 amo ng females. The rates increased sharply with age, from 0.1 at age < 45 years to 36.3 at age 75+ years (males) and from 0.1 at age < 45 years to 16.4 at age 75+ years (females). The rates for WM were comparable to those for hairy cell leukemia, but considerably lower than those fo r multiple myeloma or chronic lymphocytic leukemia. Some geographic va riation was evident, with age-adjusted rates among white males ranging from 2.2-7.8 across registries. There was no significant change in ra tes over the 7-year study period (P > 0.05). The markedly higher rates for WM among whites than blacks stand in contrast to multiple myeloma , which occurs twice as often among blacks. CONCLUSIONS. This survey p rovides new data regarding the incidence patterns of WM in the U.S. Ho wever, further epidemiologic studies with biomarkers are needed to def ine the environmental, genetic, immunologic, and viral determinants of this rare but distinctive disorder. (C) 1998 American Cancer Society.