Cancer cases to rise steeply by 2050: What are the causes?

Certain cancer types are more common, and some carry an overall higher mortality rate worldwide. IARC collects data on these numerous areas to help create a more complete picture of the effects of cancer, allowing for brainstorming strategies to address the problem.

According to one of the IARC reports worldwide, the top three most common cancers in 2022 were lung, breast, and colorectal cancer. Among men and women, lung cancer accounted for 12.4% of all cancer cases.

Among men, the top three most common cancers were lung, prostate, and colorectal. Among women, the top three most common cancers were breast, lung, and colorectal, with breast cancer accounting for 23.8% of all new cancer cases among females in 2022.

Worldwide, the mortality rate for lung cancer is currently the highest, with an overall 16.8% mortality rate. It accounted for over 2.4 million cases worldwide and over 1.8 million deaths. Incidence, mortality, and prevalence were highest in Asia and second highest in Europe.

Similarly, breast cancer accounted for over 2.3 million cases worldwide. In mortality, it ranked number four and accounted for almost 670,000 deaths.

Mortality from cancer varies significantly throughout the world. The most stark difference is between countries with a very high human development index and countries with a low human development index.

Among countries with a low human development index, there were 811,014 new cancer cases and 543,337 deaths. In contrast, among countries with a very high human development index, there were 9,296,171 new cancer cases and only 3,643,502 deaths.

WHO estimates that the number of new cancer cases in 2050 will rise 77% to a total of 35 million cases.

While high human development countries will likely still experience some of the highest incidence levels, low and medium human development index countries will see a steep increase from previously.

WHO further estimates this will lead to high mortality levels in low and medium human development index countries. It estimates that in 2050, the mortality amounts in these countries may almost double.

The burden of cancer is related to several factors. The statement from WHO suggests that people in countries with a lower human development index may receive diagnoses later and have a lower chance of access to quality treatment. This can significantly increase the risk of poor cancer health outcomes.

Another struggle is people’s ability to get governmental assistance for cancer-related services. In this statement, the WHO referenced survey data from 115 countries on components of their universal health coverage.

This survey data found that only 39% of these countries included basic cancer management as part of health benefit packages for their citizens.

Health benefit packages also varied considerably between countries. For example, high-income countries were more likely to have lung cancer-related services, radiation services, and stem-cell transplantation as part of their health benefit packages than low-income countries were.

Environmental factors and lifestyle choices also contribute to cancer’s impact. For example, the WHO statement suggests that the increase in lung cancer cases is related to the continued use of tobacco in Asia. They also note that the data reflects increases in the aging population and population growth.

Alcohol use, tobacco use, and obesity continue to contribute to cancer rate increases overall. Exposure to air pollution is also a likely contributing factor.

Surgical oncologist Dr. Anton Bilchik, who is chief of medicine and Director of the Gastrointestinal and Hepatobiliary Program at Saint John’s Cancer Institute in Santa Monica, CA, speculated about a few other factors that may be contributing to cancer rate increases.

“There are major disparities in healthcare and the disproportionate increase in cancer cases among poorer countries is striking. The rise is related to poor nutrition, smoking, lack of public awareness and limited access to screening. Furthermore, there is a higher mortality once diagnosed for similar reasons — lack of access to modern surgical techniques and effective systemic therapies,” he told us.

Private practice oncologist and current president of Maryland Oncology Hematology, Dr. George A. Sotos, offered further potential contributing factors:

“A report released by the WHO on February 4, documented a significant increase in global cancer incidence. A study in the British Medical Journal [BMJ Oncology] in September 2023 described a similar significant increase in cancer in people less than 50 years old. It is difficult to pinpoint the exact reasons for this rise. Some of the increase can be attributed to increased screening efforts and increased reporting, and some to a growing and aging population, but the authors of both studies also propose that dietary factors, including obesity and alcohol consumption, and environmental factors such as pollution and especially tobacco use, were major contributors.”

While the eradication of cancer is unrealistic, there is the possibility for mitigation and prevention. Action can take place at many levels to improve access to screening and treatment.

Various governments and medical organizations can help by raising awareness and increasing understanding of cancer risk. The statement from WHO suggests that countries could reexamine prioritizing cancer in health benefits packages.

People can also take steps at the individual level to cut down on personal risk factors. For example, people can quit smoking to help decrease their risk for several cancer types.

They can also seek to follow a balanced diet, maintain a healthy weight, and limit alcohol use. They can further discuss their doctor’s recommendations for cancer screening and follow-up.

Dr. Bilchik noted that:

“Many cancers are completely preventable. This can only be accomplished with a significant investment in cancer prevention education and better access to cancer screening. Individuals should recognize the importance of a healthy lifestyle, exercise, the avoidance of smoking, a healthy diet as ways of preventing cancer.”

Dr. Shana O. Ntiri, associate professor in the Department of Family & Community Medicine, executive director of the Mini Medical School at the University of Maryland School of Medicine and Medical Director of the Baltimore City Cancer Program, and senior medical advisor in the Office of Community Outreach and Engagement at the University of Maryland Marlene and Stewart Greenebaum Cancer Center, commented with her thoughts on prevention to Medical News Today.

“The report names lung, breast, and colon as the three major cancer types in 115 countries including the [United States,” she told us. “These are three cancers for which we know prevention-focused behavioral changes and screening can significantly decrease cancer morbidity and mortality.”

“Stopping tobacco use, maintaining a healthy weight, eating nutritious meals and being active are key ways that people can reduce their risk of getting cancer. It’s also important to keep up with regular screenings, such as mammograms for breast cancer, colonoscopies for colorectal cancer and PSA testing for prostate cancer,” Dr. O Ntiri advised.