Jan 29, 2026
3 min read
These causes are thought to be poor diet, obesity or excessive use of antibiotics.
Cancer growth in young people in 2026: 8,000 cases under 39 years of age.
It is assumed that the underlying causes are inadequate diet, obesity or excessive use of antibiotics.
The Spanish Society of Medical Oncology (SEOM) announced this Monday that new cancer patients will grow by 2% this year in Spain and will exceed 300,000 diagnoses for the first time.Of these, 8,000 cases will be found in young people between the ages of 20 and 39, according to SEOM estimates, especially in the breast and thyroid.
The Cancer Data in Spain 2026 report, prepared by the scientific association in collaboration with the Spanish Cancer Registry Network (Redecan), shows that colon and rectal tumors are the most common with 44,132 this year.In addition to breast cases, with 38,318 cases and lung cases, with 34,908 cases.
Some of the factors that will lead to an increase in diagnoses to an estimated 301,884 will be a growing and aging population.However, the study also highlights that increased rates of early detection or avoidable risk factors lead to increased survival rates, which have doubled over the past 40 years.
The president of SEOM, Javier de Castro, for his part, appealed to the importance of not being "cautious" and encouraging self-care among people through activities such as exercise, which reduces the risk by 30%.
The increase occurs in the age group between 20 and 29 years
Con estos datos, España mantendrá la misma tendencia al alza prevista en todo el mundo, ya que se calcula que, para 2050, se detectarán 32,6 millones de nuevos cánceres, 350.000 de ellos en nuestro país.
As for the increase among young adults, data from Globocan – a tool that evaluates cancer data worldwide – shows that more than 1.2 million new tumors were diagnosed in this age group in 2022.
In Spain, Redecan (Spanish Cancer Registry Network) estimates that by 2026, more than 8,000 cancer diagnoses will be registered in people aged between 20 and 39.Among women this will be a majority, with 4,800, and in contrast to men, with 3,400;the breast represents 20.5% and the thyroid 13.4%.
In this regard, Redecan President Jaume Galcerán pointed out that since 1994, this increase first appeared in the age group defined between 20 and 29 years old.In absolute terms,The increase was "very small", but since that year, tumors such as colon cancer or kidney tumors have indeed shown a worrying trend.
Obesity or overuse of antibiotics: possible causes in young adults
Although the exact causes are unknown, insufficient nutrition, microbiota dysfunction, obesity or excessive use of antibiotics have been suggested as triggers."We need to continue to increase research to find out why this is happening," said the oncologist.
On the other hand, Isabel Etxavaria, a member of the Spanish Society of Medical Oncology, stated that, instead of increasing the screening age, we must focus on sticking to what already exists, because although breast screening is "very good", others, such as colon screening, have much worse rates.
However,Experts say the main risk factors to avoid are: smoking;alcoholair pollutionThey point to an unhealthy diet with a sedentary lifestyle and insufficient consumption of fruit and vegetables.
Lung cancer, the first cause of oncological death in women
The disease in men will not be the same as in women: in men the prostate gland, rectum, lung and bladder are most common, while in women the breast and rectum and anus are more common.
Next will be lung cancer - the most common cause of cancer death in Spain - whose incidence, unlike people, which show a downward trend, will continue to rise as a consequence of their later admission in the habit of smoking.
However, it continues to worsen for men (16,606 deaths from this cause in 2024), with death rates almost three times those of the next two, prostate (5,967) and colon (5,913).And for women, it has passed breast cancer for the first time as the leading cause of death (6,691 compared to 6,563), followed by colon cancer (4,538) and pancreatic cancer (4,090).
It is still the most deadly because of the fact that about half of the patients are found at a very advanced stage, in addition to the fact that the measures needed to get it have more impact than other cases, and that it is a very stigmatized disease, so less is invested in it.
"We need to start taking measures in the population at risk and reduce smoking. Almost 35% of the population continues to smoke in various forms, including electronic cigarettes," said the SEOM chairman, recalling that 20% of cases also occur among non-smokers.
