Temporal Trends in Mortality from Hairy Cell Leukemia in the United States: Evidence from SEER Registries

Hairy Cell Leukemia (HCL) is a rare indolent B-cell malignancy with favorable long-term survival; however, population-level mortality trends remain incompletely characterized. We evaluated national mortality patterns and sex-specific disparities in HCL in the United States over two decades.

Mortality data were obtained from the Surveillance, Epidemiology, and End Results (SEER) 21 Registries Database (excluding Illinois) for the period 2000–2022. Deaths attributable to HCL were identified using ICD-O-3 morphology codes. Crude and age-adjusted mortality rates per 100,000 population were analyzed overall and stratified by sex. Age-adjusted rates were standardized to the 2000 U.S. standard population. Temporal trends were evaluated descriptively and visualized using line and bar graphs.

From 2000 to 2022, crude mortality rates for HCL demonstrated a mild upward trend nationally, primarily driven by increases among males. Mortality rates remained consistently higher in males compared with females throughout the study period. Female mortality rates were largely stable, whereas male rates showed modest increases over time. After age adjustment, mortality rates for both sexes remained largely unchanged, averaging approximately 0.10 per 100,000 among males and 0.05 per 100,000 among females, with no significant temporal escalation observed.

Mortality from Hairy Cell Leukemia in the United States has remained relatively stable over the past two decades despite slight increases in crude mortality rates. The persistent male predominance in HCL-related mortality suggests underlying biological or behavioral factors influencing disease outcomes. Continued epidemiologic surveillance and sex-specific investigations are warranted to further elucidate long-term mortality patterns in this rare hematologic malignancy.