A disturbing trend is emerging in cancer statistics globally and within brazil: a rising incidence of the disease in younger adults. While traditionally considered a disease of older age, recent data reveals a notable increase in diagnoses among individuals under 50, prompting medical organizations to re-evaluate screening recommendations and investigate potential contributing factors. This report examines the latest research, including studies analyzing trends across 42 countries, and explores the challenges and potential solutions surrounding early-onset cancers.
A concerning trend is emerging in cancer diagnoses: an increasing number of cases are being detected in younger adults. While cancer rates historically rise with age, experts are now observing a shift, with the disease becoming more prevalent even in individuals under 50. This rise is occurring alongside an overall increase in cancer as a leading cause of death, particularly in higher-income countries, sometimes surpassing heart attacks and strokes.
Certain cancers are driving this trend, notably colorectal cancer. This was the type of cancer that tragically took the lives of Brazilian singer Preta Gil, who passed away in 2025 at age 50, and actor Chadwick Boseman, star of “Black Panther,” who died in 2020 at 43. More recently, in 2024, Kate Middleton, the Princess of Wales, publicly announced her cancer diagnosis at age 42 following abdominal surgery.
A study published in 2023 in JAMA Network Open analyzed data from 562,145 cancer cases in the United States between 2010 and 2019, focusing on individuals under the age of 50. Researchers found that the incidence of early-onset cancers increased during this period, growing at an annual rate of 0.28%. In contrast, cancer incidence decreased by 0.87% per year among those over 50. Gastrointestinal cancers showed the most significant growth, increasing by 2.16% annually.
Further research, published in October 2025, analyzed 13 different cancer types across 42 countries. The study revealed increased incidence rates among younger adults in most of the countries examined for six cancer types: thyroid, breast, colorectal, kidney, endometrial, and leukemia. In 69% of the countries studied, the growth in cancer cases was more pronounced in younger individuals compared to older adults.
An additional study, appearing in the October 2025 issue of Annals of Internal Medicine, examined cancer trends in 42 countries between 2003 and 2017, comparing adults aged 20-49 with those over 50. Six cancers – thyroid, breast, colorectal, kidney, endometrial, and leukemia – showed increased incidence among young adults in most countries. With the exception of colorectal cancer, increases were also observed in older adults. Notably, the growth of colorectal cancer was greater among young people than those over 50 in 69% of the territories analyzed.
While global data is emerging, a comprehensive analysis of cancer trends within Brazil is still underway. Luís Felipe Martins, head of the Surveillance and Situation Analysis Division at the Instituto Nacional de Câncer (INCA), explains that while some studies indicate a growth in cancer rates across the population, a definitive national trend hasn’t yet been established.
A study led by Martins focused on the northern region of Brazil. In Manaus, for example, cancer incidence increased by 2.7% annually between 2003 and 2018 for men and 3.2% for women. In Belém, the increase was 1.65% per year for men, with incidence remaining stable for women.
These data come from Brazil’s Population-Based Cancer Registries (RCBP), which collect information on new cases and allow for trend analysis over time. However, the Brazilian system faces limitations, covering only about a quarter of the population. Furthermore, the infrastructure for collecting and reporting cancer incidence data suffers from underfunding and delays in data entry, hindering accurate assessments.
Despite these data challenges, medical societies are proactively adjusting recommendations. Several organizations have lowered the recommended age for initiating cancer screening for certain types. In the United States and other countries, colonoscopies are now recommended starting at age 45, rather than 50. In Brazil, mammograms are now offered through the public healthcare system starting at age 40, as of September 2025.
According to Angélica Nogueira, president of the SBOC (Brazilian Society of Clinical Oncology), this change is justified by the data: 40% of breast cancer diagnoses in Brazil now occur in women under 50. “If we begin screening at age 50, we’ll see diagnoses at more advanced stages of the disease, which reduces the chance of cure and necessitates more aggressive treatments,” she explains.
Beyond age, researchers are investigating the underlying causes of this increase in cancer among younger populations. While genetics play a role – mutations that increase cancer risk exist and explain some individual cases – they account for only about 12% of all tumors.
“While we can say that young patients have a higher frequency of hereditary cancer, we can’t attribute the increase in incidence solely to heredity,” says Augusto Antoniazzi, a researcher and coordinator of the oncogenetics department at Hospital de Amor in Barretos.
Changes in social factors and lifestyle are increasingly suspected as key contributors, including rising obesity rates, sedentary lifestyles, the consumption of ultra-processed foods, environmental exposure to carcinogens, and alcohol and tobacco use.
Nogueira believes obesity has the potential to be a central factor. Two-thirds of the Brazilian population is overweight, and obesity is linked to 13 types of cancer, according to the World Health Organization.
Dietary changes are also under scrutiny. “What we ate in the past doesn’t necessarily have the same composition today,” says Maria Ignez Braghiroli, a specialist in gastrointestinal tumors at Oncologia D’Or.
The connection between obesity, inactivity, ultra-processed food consumption, and cancer development is thought to involve inflammation, which is also linked to aging, alcohol and tobacco use, UV exposure, and other factors. Chronic inflammation can lead to unsuccessful repair attempts by the body, triggering mutations and cellular changes that ultimately contribute to tumor development.
Improved diagnostic capabilities – more sensitive and accessible tests – and changes in diagnostic criteria over the decades may also contribute to the observed increase.
The rise in cancer cases among young people presents challenges for healthcare systems. One key issue is delayed diagnosis. Historically, cancer has been viewed as a disease of aging, which has shaped medical training and clinical practice. When a 30-year-old patient presents with persistent abdominal symptoms, many doctors may not initially consider cancer as a primary diagnosis.
Even when screening is recommended, adherence rates remain low. In the case of mammography, only about 30% of eligible women participate in screening, and this number may be overestimated.
A more personalized approach to screening is being considered, recognizing that individuals of the same age may have vastly different screening needs based on family history, genetics, and other risk factors.
Beyond potential diagnostic delays, the impact of cancer on individuals under 50 can be particularly significant. “This is a population at the peak of their productive years, facing issues related to fertility, family building, and financial stability. Therefore, the psychological, emotional, and socioeconomic impact is very substantial,” says Braghiroli.
