How Common Is Lymphoma?

More Cases of NHL Expected Due to Aging Population and Risks

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Some types of lymphoma are on the rise.

Is lymphoma becoming more common? Globally, no huge increase in lymphoma incidence has been reported. So, in one sense, you could say that lymphoma is not becoming more common.

But there’s a catch. First, there are 70+ different types of lymphoma, some of which may be on the rise. Second, the description 'becoming more common' might cause a few scientists to gasp and faint. For more on this, see Populations, Risks and More, below.

Non-Hodgkin’s Lymphoma On The Rise

Some types of lymphoma have been increasing, and this trend is predicted to continue. This appears to be the case with non-Hodgkin’s lymphoma (NHL) and some of its subtypes. Overall, an American's lifetime risk of getting NHL is currently estimated to be about 1 in 50. NHL numbers have increased slightly over the last 30 years.

According to the American Cancer Society, the risk of developing NHL increases throughout life, and “…the aging of the American population is likely to lead to an increase in NHL cases during the coming years.”

Particular types of NHL have also shown increasing incidence. According to the July 2012 issue of the “Canadian Journal of Gastroenterology,” incidence rates of primary gastrointestinal NHL have been on the rise in North America.

United States vs. Japan

Compared to Japan, the increase in North America seems rather flat. A recent report showed the incidence of blood cancer in Japan was approximately one-half that in the US, but has been increasing significantly, whereas changes seen in the United States were not significant.

The substantial increase in Japan relative to the United States has suggested to some investigators that environmental exposures, such as an increasingly Western lifestyle, may be causing this increase in Japan.

Israel: World’s Highest Rate of NHL

According to the Jerusalem Post, Israel is in first place among 20 countries in the rate of NHL.

This was one of the revelations at a press conference by the Israel Cancer Association and the Health Ministry to mark World Cancer Day. The cause is unknown.

Leave it to The Swiss

In Switzerland, they already have projections for cancer incidence up to 2019. Estimating the rates of cancer at future time-points, they note, is essential to plan for the future:

Among men, the largest increase is anticipated for melanoma +54 percent, thyroid +45 percent, non-Hodgkin lymphoma +43 percent, and prostate +37 percent.

For women, it is projected that cases of lung and oral cavity cancers will increase by +48 percent and +38 percent, respectively; those of thyroid by +45 percent and non-Hodgkin lymphoma by +36 percent.

Population, Risks, and More

Cause and effect tends to be hard to prove in cancer, and any blip or trend can offer valuable information. If one group is developing a particular kind of cancer in higher proportion than is expected, that’s information doctors and scientists need to know. These are important clues that sometimes they lead to discoveries about cause and effect.

When lymphoma cases increase in a group, it might be from any number of things, such as: an exposure to a cancer-causing agent; a genetic trait that clusters in a particular community or ethnicity; an improvement in the way doctors are able to detect lymphoma; an increase in the number of people going to doctors to be tested, etc.

When epidemiologists examine the numbers and trends, they pay attention to  demographics  and risks such as exposures, genetics and other predisposing or preventive factors. There are two very basic and different ways they talk about how common any something is. The number of new cases in a given time is called the incidence. Something can be highly prevalent, but if there are no new cases, the incidence will be zero. Unfortunately with lymphoma, there are always new cases. The number of total cases is called the prevalence, and it reflects both new and old cases; as long as a person is still alive, he or she counts in the prevalence figures.

Sources

American Cancer Society. What are the key statistics about non-Hodgkin lymphoma? http://www.cancer.org/cancer/non-hodgkinlymphoma/detailedguide/non-hodgkin-lymphoma-key-statistics Accessed March 2015.

Rapiti E, Guarnori S, Pastoors B, Miralbell R, Usel M. Planning for the future: cancer incidence projections in Switzerland up to 2019. BMC Public Health. 2014;14:102.

Chihara D, Ito H, Matsuda T, et al. Differences in incidence and trends of haematological malignancies in Japan and the United States. British Journal of Haematology. 2014;164(4):536-545.

Israel: Worlds Highest Rate of non-Hodgkin’s Lymphoma. http://www.jpost.com/Israel-News/Health/Israel-Worlds-highest-rate-of-non-Hodgkins-lymphoma-390037. Accessed March 2014.

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