In order to make a comparison of the age-specific lymphoma incidence rate between Japan and other countries, we abstracted cancer incidence rate from the Cancer Incidence in Five Continents Vol. XI (CI5) (1). The International Agency for Research on Cancer provides the CI5 databases on the incidence of cancer recorded by cancer registries (regional and national) worldwide. We used cancer incidence rate in five countries in Asia (China, India, Japan, Republic of Korea and Thailand), three countries in America (the USA, Canada and Brazil), two countries in Oceania (Australia and New Zealand) and four countries in Europe (the UK, France, Germany and Italy). Some countries have plural cancer registries and we aggregated all the registries to calculate the incidence rate in the countries from the CI5-XI database. The period of years at cancer diagnosis were from 2008 to 2012. Lymphoma included Hodgkin lymphoma coded as C81, and non-Hodgkin lymphoma coded as C82-C86 and C96 based on ICD-10.
Figures 1 and 2 show the age-specific lymphoma incidence rates by 5-year age groups for the selected countries in males and females, respectively. In all countries studied, the incidence rates are higher in males than in females. By age group, the incidence rate was about twice as high in males under 10 years of age as in females, and about 1.5 times as high in males over 10 years of age, with no marked differences among regions or countries. The incidence rate by age group tends to increase with age in almost all countries, but in Asia, except Japan, the incidence rates do not seem to change much after the age of 70 or 75. The incidence rates for both males and females were basically higher in America and Oceania, followed in order by Europe and Asia. With specificities in Japan, the rates were closer to those in Europe, and in Brazil in America with slightly lower rates than those in Europe and about the same as those of Japan. However, looking at the differences between countries in detail for those under 50 and over, Japan has the same incidence rates as Europe, America and Oceania for those over 50, while the rates for those under 50 were as low as in Asian countries. Brazil also showed a difference trend between younger and older age group. The incidence rates in Brazil were as low as those of other countries in Asia for males over 40 years old and for females over 30 years old, and for younger age groups, the incidence rates were as high as those of other countries in Americas.
Age-specific lymphoma incidence rate per 100,000 people in male. The incidence rate increase with age except in Japan. And the rates are basically higher in Americas and Oceania, followed in order by Europe and Asia.
Age-specific lymphoma incidence rate per 100,000 people in female. The incidence rates for females are lower than those for males in all countries. The rates are basically higher in Americas and Oceania, followed in order by Europe and Asia.
Note: Data were downloaded from the Global Cancer Observatory (GCO), which is an interactive web-based platform presenting global cancer statistics (https://gco.iarc.fr/). Responsibility for this presentation and interpretation lies with the authors of this article.
Conflict of interest
We authors have no conflicts of interest directly relevant to the content of this article.
