1. For more information, see:
Hodgkin lymphoma incidence is highest in young adults and the elderly (Sept. 2014)
Hodgkin lymphoma has an unusual bimodal age distribution, with age-specific incidence rates peaking in young adults and the elderly.
This bimodal age distribution is typical for economically developed countries and likely reflects an overlap of the age distribution of two of the major subtypes of Hodgkin lymphoma: nodular sclerosis and mixed cellularity.
The causes of Hodgkin lymphoma are not well understood but past infection with Epstein-Barr virus or another common childhood infection may contribute to the unusual age distribution.
The age distribution of Hodgkin lymphoma is unusual. Unlike most cancers, which show rising incidence with increasing age, the incidence of Hodgkin lymphoma has a bimodal age distribution, peaking in two different groups: young adults and the elderly. Hodgkin lymphoma is rare in childhood, but becomes much more common in the mid to late teens, with incidence rates reaching their highest in the early to late 20s, at about five per 100,000 population. After dropping in people in their 30s and 40s, incidence rates begin rising again after age 50 and peak for a second time, although at a lower rate, among those aged 80–84 years. Because the incidence of Hodgkin lymphoma peaks in people in their 20s, it is the third most common cancer diagnosed in adolescents and young adults aged 15–29 in Ontario.
Ontario’s bimodal age distribution for Hodgkin lymphoma incidence is a pattern characteristically seen in economically developed areas of the world.1 This distribution reflects the fact that the age distribution of two of the major subtypes of Hodgkin lymphoma in developed countries (nodular sclerosis and mixed cellularity) overlap but peak at different ages.1 Nodular sclerosis is by far the most common subtype at all ages, but peaks in people aged 15–34. The mixed cellularity subtype, in contrast, is less common overall, but peaks between the ages of 45 and 84.
Reasons for the variation in incidence by age and subtype remain unclear. Past infection with Epstein-Barr virus (EBV) is known to cause both of Hodgkin lymphoma’s two most common subtypes, although it is usually more associated with the mixed cellularity subtype than with nodular sclerosis and is less frequently found in young adults than in people who are very young or very old.1 Infection with human immunodeficiency virus (HIV) is another risk factor, but it tends to be most prevalent in certain smaller high-risk subpopulations.2 Instead, in more developed countries, it has been suggested that delayed infection or a delayed response to another common childhood infection may contribute to the peak in incidence among young adults.1 Genetic susceptibility may also contribute to the development of Hodgkin lymphoma, since it can sometimes run in families.
For more information, see:
• The April 2014 Ontario cancer fact: Incidence trends for common cancers in young men vary widely. Available at
References
Melbye M and Adami H. Hodgkin’s lymphoma. In: Adami H, Hunter D, Trichopoulos D, editors. Textbook of cancer epidemiology. New York: Oxford University Press; p. 520–534.
Cancer Care Ontario. Cancer Risk Factors in Ontario: Evidence Summary. Toronto, Canada, Available at
Citation: Cancer Care Ontario. Cancer Fact: Hodgkin lymphoma incidence is highest in young adults and the elderly. September
Available at
Prepared by staff in Prevention and Cancer Control.