In 2018, 9.6 million people died of cancer according to the World Cancer Observatory. A figure that is likely to increase in the coming years. Because since 1990, the number of early-onset cancers, that is to say diagnosed in adults under 50, has increased dramatically worldwide, according to a scientific article published in the journal Nature Reviews Clinical Oncology, September 6, 2022. That the number of people with this disease has been on the rise in modern society since the 1940s-1950s is not a discovery but early onset cancers are.
To confirm this, the researchers looked at people born in the 1950s and 1960s and studied their cancer rates from the 1990s. They looked at data for 14 types of cancer, whether cancer breast, liver, kidney, head and neck. Thus, thanks to global data, they realized that the diseases studied were on the increase in adults under 50 between 2000 and 2012.
An emerging global epidemic
“We found that this risk increases with each generation”explains one of the researchers, Shuji Ogino, a pathologist and epidemiologist at Brigham and Women’s Hospital in Boston to the media. ScienceAlert. He adds : “For example, people born in 1960 experienced a higher risk of cancer before they turned 50 than people born in 1950 and we expect this level of risk to continue to increase in successive generations.”
The researchers’ goal was to find out if early-onset cancer had become an emerging global epidemic. According to the results, the answer is yes, since the 90s in particular.
The increase in screenings has necessarily contributed to this phenomenon. The more we search, the more we detect. But that’s only part of the explanation.
Especially since the researchers note that certain early-onset cancers are increasing even in countries that do not have a screening program… The reason, then? The change in our lifestyles, our environment… or even our diet and the appearance of ultra-processed foods.
Eight rising cancers linked to the digestive system
“Of the 14 rising cancer types we studied, eight were related to the digestive system”, epidemiologist Tomotaka Ugai of Harvard Medical School tells ScienceAlert. Not to mention sugary drinks, obesity, physical inactivity and alcohol consumption which have all increased significantly since the 1950s. Another notable fact: unlike adults who have not radically changed their sleep duration, children sleep much less than a few decades ago. All of this could interact with genetic susceptibilities to cancer and how the disease functions, according to the study.
The researchers do not intend to stop there: they wish to continue their work and set up cohort studies followed over time, in order to be able to observe the evolution of the health of young children over several decades and determine what made that person had cancer in the past and today. They also want to make the public and health professionals more aware of the risks of early cancers.