This increase is not limited to young people under 50; similar trends are observed among the older generation as well.
The study, published this week in the Annals of Internal Medicine, examined cancer data from 42 countries across five continents from 2003 to 2017.
Researchers analyzed 13 types of cancer that have been reported to be becoming more common among youth.
The findings confirm that certain types of cancer are indeed increasing among people aged 20 to 49. These include thyroid cancer, breast cancer, colorectal cancer, kidney cancer, endometrial cancer, and leukemia—all of which showed an increase in more than 75% of the countries where the study was conducted.
The largest increase was observed in thyroid cancer, with an average annual growth of 3.57%, followed by kidney cancer (2.21%) and endometrial cancer (1.66%).
As for colorectal cancer, its incidence among people under 50 increased on average by 1.45% per year. While most types of cancer showed growth among both youth and the elderly, colorectal cancer became an exception.
In nearly 70% of countries, new cancer diagnoses were recorded among youth faster than among older individuals.
The authors of the study emphasize that the observed trends indicate the presence of common factors such as rising obesity rates, dietary changes, and antibiotic use.
The Elderly Remain the Primary Risk Group
Despite the alarming data on "youth cancer," researchers caution against focusing preventive efforts solely on the young. Although the incidence of certain forms of cancer among people under 50 is rising, the overall number of cases remains significantly higher among the elderly.
For example, in 2022, 50,000 women under 50 in the U.S. were diagnosed with breast cancer, while among women over 50, there were more than 210,000 such cases.
Researchers have called for further studies into the causes of the rising incidence.
The data obtained could help prioritize future research and clinical strategies, including the need for specialized treatment and support for young cancer patients, the report concludes.
However, is there really an increase in "youth cancer," or is it related to improved diagnostics?
A study published last month suggests that much of the increase in incidence may be linked to overdiagnosis rather than a true rise in cases.
In a publication in JAMA Internal Medicine, scientists analyzed eight types of cancer with the highest increase in incidence among people under 50—thyroid, anal, kidney, small intestine, colorectal, endometrial, pancreatic, and myeloma cancers.
The study showed that since 1992, the number of diagnosed cases of these diseases has doubled, yet the mortality rate has remained surprisingly stable. This may indicate that the rise in reported cases is largely associated with improved diagnostics rather than a true increase in incidence.
The authors of the study warn that viewing early-stage cancer as an epidemic could lead to exaggeration of the problem and undesirable consequences.
For instance, unnecessary diagnoses can become a significant emotional, physical, and financial burden for patients, subjecting healthy young individuals to invasive treatments and prolonged monitoring that do not provide real health benefits.
