Recent incidence and secular trends in Hodgkin's disease and its histologic subtypes.

Incidence data from national cancer surveys (1947, 1969-71, 1973-80) in selected regions of the United States were used to describe the epidemiology of Hodgkin's disease (HD) in whites over all regions by age, sex and Rye histologic subtype in the 1970s, and time trends for HD overall. Before 1971, rates increased in young adults, notably men, and in older persons. During the 1970s, rates in children were stable, but young adult rates were high and rose slightly, particularly among women; both trends reflected elevated incidence of Nodular Sclerosis, the only subtype with increasing rates. For adults over 40, rates of all subtypes declined after 1969-71. Thus HD incidence in this country is not static, even over the last decade. Rate stability in younger children may indicate disappearance of environmentally caused HD. Incidence declines for older persons suggest a cohort effect, depletion of young adult susceptibles, or improvements in diagnostic accuracy.