Cancer cases worldwide are expected to increase 77% by 2050, study shows

Around the world each year, tens of millions of people are told they have cancer, and millions die from the disease. Now, a report from the American Cancer Society projects that by 2050, the number of people with cancer could increase by 77% .

The report, published on Thursday (4) in the journal CA: A Cancer Journal for Cliniciansfound that in 2022 – the most recent year for which data was available – around 20 million cases of cancer have been diagnosed along with 9.7 million cancer deaths .

These estimates suggest that about 1 in 5 people who are alive now will develop cancer during their lifetime, and about 1 in 9 men and 1 in 12 women will die from the disease.

When it comes to the number of cases around the world, “we believe that number will reach 35 million by 2050, largely due to the increase in the elderly population,” says William Dahut, scientific director of the American Cancer Society.

The new report states that the population growth and aging are key factors in the size of the global cancer burden, with the global population of around 8 billion people in 2022 projected to reach 9.7 billion by 2050.

But if more people also use tobacco and more have obesity, along with other cancer risk factors, the projected number of cancer cases could be even higher, Dahut warned, especially in low-income countries.

“Many of the risk factors for cancer that we have traditionally seen in high-income countries, like tobacco and obesity, those same factors are now moving into low-income countries,” Dahut said, adding that this trend is concerning.

“These are countries that do not have the resources to detect cancer early, treat cancer appropriately and prevent it in the same way that is often done in other countries,” he said. “We are concerned that we are going to see increased incidence rates, increased mortality rates, especially in low-income countries, where cancers are now being driven not just by traditional risk factors but also by external things like tobacco and obesity.”

Most common cancer in the world

The new study includes global data on the incidence and death from cancer in the Global Cancer Observatorya WHO (World Health Organization) database.

The data shows that lung cancer was the most diagnosed cancer worldwide in 2022, with almost 2.5 million new cases and over 1.8 million deaths.

Overall, the 10 most common cancers in both men and women accounted for more than 60% of newly diagnosed cancer cases and cancer deaths, according to the report.

The most common cancer types are lung, breast in women, colorectal, prostate, stomach, liver, thyroid, cervical, bladder and non-Hodgkin's lymphoma, according to the report. Lung cancer was also the leading cause of cancer death, followed by colorectal, liver, breast in women, stomach, pancreas, esophagus, prostate, cervical, and leukemia.

Cervical cancer was the leading cause of cancer death in 37 countries, mainly in sub-Saharan Africa, South America and Southeast Asia, according to the report. The HPV or human papillomavirus vaccine may reduce the risk of cervical cancer, but overall, only about 15% of eligible girls received the vaccine , according to the American Cancer Society. There are also disparities in screening for cervical cancer.

“With more than half of the world's cancer deaths potentially preventable, prevention offers the most cost-effective and sustainable strategy for cancer control,” says Ahmedin Jemal, senior vice president of health equity surveillance and science at the American Society of Cancer. of Cancer and senior author of the study, in a press release. “Eliminating tobacco use alone could prevent 1 in 4 cancer deaths or approximately 2.6 million cancer deaths annually.”

While the causes of cancer can be complex, genetic or environmental, “about 50 percent of cancers are preventable,” says Bilal Siddiqui, an oncologist and assistant professor at the University of Texas MD Anderson Cancer Center who was not involved in the new report. , in an email.

“All patients should talk to their doctors to ensure they receive age-appropriate cancer screenings, and it is important to make the essential lifestyle changes that can reduce our cancer risk, including quitting smoking, reducing alcohol consumption and stay physically active”, he adds.

Prostate cancer cases expected to double

Concern also grows around the prostate cancer . A separate report, published on Thursday (4) in the newspaper The Lancetprojects that the number of new cases of prostate cancer annually will increase from about 1.4 million in 2020 to 2.9 million by 2040 .

Prostate cancer is one of the most commonly diagnosed cancers, accounting for approximately 15% of new cancer cases in the United States. Globally, prostate cancer is the most common cancer in men in 112 countries according to the new report, from The Lancet Commission on Prostate Cancer.

“In terms of the global health burden of prostate cancer, I think the numbers are somewhat surprising but expected at the same time. Globally, the population is aging, and prostate cancer is primarily a disease of aging,” says Brandon Mahal, a radiation oncologist and translational epidemiologist at the Sylvester Comprehensive Cancer Center at the University of Miami Miller School of Medicine, who authored the new report.

“As we continue to increase life expectancy, especially in low- and middle-income countries, aging-related diseases – specifically, such as a common cancer like prostate cancer – can be expected to become a greater burden,” completes Mahal.

He added that prostate cancer continues to disproportionately affect the black community, “although there is some increase overall in all countries.”

The new report makes recommendations to address the “four highest priority areas” related to prostate cancer. Recommends modifying ways to detect prostate cancer early, avoiding overdiagnosis and overtreatment of trivial diseases; improve methods to empower patients with health information and potentially facilitate the use of artificial intelligence; implement targeted guidelines for therapies, especially surgery and radiotherapy; and invest in research.

The commission's report puts into perspective the “critical need for strategies for early diagnosis and effective treatment of this disease,” says Siddiqui in the email.

“The Commission made four recommendations to help improve diagnosis and management and reduce deaths from prostate cancer,” it states. “These are smart solutions that our governments and health funding agencies should support and could help reduce lives lost to prostate cancer.”

“Cancer is a tidal wave coming in”

Tobacco remains “the leading cause of lung cancer,” according to a new report from the American Cancer Society, which adds that the disease is largely preventable through effective tobacco control policies and regulations. As for other types of cancer, reducing excess body weight, reducing alcohol consumption, not smoking, and increasing physical activity can help lower a person's risk.

“Although we see lung cancers that are not related to smoking, the leading cause of lung cancer is smoking. And obviously, there is still a lot of work to be done in the US and elsewhere to continue to address the tobacco epidemic,” comments Harold Burstein, an oncologist at the Dana-Farber Cancer Institute and professor at Harvard Medical School, who was not involved in the new American Cancer Society report.

“Interestingly, pollution and other environmental air exposures likely increase the risk of lung cancer in many parts of the world. So efforts to improve clean air or reduce exposure to air pollution are another really important thing to think about,” says Burstein.

“Other things people can do to reduce their cancer mortality include screening for early cancer detection and better outcomes. In the US, we have very vigorous opportunities for screening with mammography, colonoscopy, and Pap tests, but these are still often underutilized by many parts of our society,” he says. “In more advanced economies like the US, we have seen notable declines in death rates from breast cancer and colon cancer, probably about half of that due to early detection.”

The new report details how many low-income countries have high cancer mortality rates despite the low incidence of cancer, mainly due to the lack of access to screening tools to detect the disease early and advanced treatment services.

“The report helps highlight not only these global cancer trends, but also how cancer is becoming a 'major health problem' in low- and middle-income regions of the world,” says Burstein. “Cancer is a tidal wave coming into your communities,” she says.

“They don’t have screening mammograms in most of sub-Saharan Africa. They don't have screening mammograms in China. They don’t have routine colonoscopies in many parts of the world,” she says. “The report says that the prevalence of cancer will double in low- and middle-income countries over the next 25 years. Therefore, dealing with both the increasing prevalence, the need for early detection and screening, and then the complex treatment and care of cancer patients will be a huge challenge for healthcare systems that are already overburdened.”