Cancer cases worldwide are expected to surge 77% over the next quarter century, fueled largely by an aging population and unfavorable lifestyle behaviors like smoking, poor diet, and physical inactivity, according to a new report.
An estimated 35 million people globally will be diagnosed with cancer in 2050, up significantly from 20 million cases in 2022, projects the World Health Organization’s International Agency for Research on Cancer (IARC).
While highly developed nations will see the greatest absolute rise in new cancer cases, lower income countries will experience a disproportionate spike. The IARC forecasts a 142% increase in cancer rates for low-development countries by 2050 compared to 99% for medium-development nations.
“The impact of this increase will not be felt evenly across countries of different [development] levels,” said Dr. Freddie Bray, head of IARC’s Cancer Surveillance Branch. “Those who have the fewest resources to manage their cancer burdens will bear the brunt of the global cancer burden.”
Cancer care disparities exist not only between wealthy and poor regions but also within individual countries, noted Dr. Cary Adams, head of the NGO Union for International Cancer Control. “Where someone lives should not determine whether they live. This is not just a resource issue, but a matter of political will,” she said.
Lung Cancer Edges Out Breast Cancer as Most Common Diagnosis Worldwide
After being surpassed by breast cancer as the most commonly diagnosed cancer globally in 2020, lung cancer moved back into the lead in 2022, according to the IARC report. Persistent tobacco use in Asia helped push lung cancer case rates slightly ahead of breast cancer over the past two years.
The five most commonly diagnosed cancers worldwide in 2022 were:
- Lung cancer: 2.5 million new cases
- Breast cancer: 2.3 million
- Colorectal cancer: 1.9 million
- Prostate cancer: 1.5 million
- Stomach cancer: 970,000
While lung cancer diagnoses edged out breast cancer overall, breast cancer remained the top diagnosis in the majority of individual countries – 157 out of 185.
In 2020, the last year for which data is available, the most common cancer diagnoses were:
- Breast cancer: 2.3 million
- Lung cancer: 2.2 million
- Colorectal: 1.9 million
- Prostate cancer: 1.4 million
- Stomach cancer: 1.1 million
For women, breast cancer remained the most commonly diagnosed cancer and the leading cause of cancer death globally in 2022. Lung and colorectal cancers ranked second and third for incidence and mortality in women.
Meanwhile, lung cancer was the most diagnosed and deadliest cancer for men worldwide, followed by liver and colorectal cancers.
Lung Cancer Remains #1 Cancer Killer Globally and in U.S.
In addition to being the most commonly diagnosed cancer, lung cancer was also the deadliest cancer globally in 2022, causing 1.8 million deaths. Colorectal and liver cancers ranked second and third:
- Lung cancer: 1.8 million deaths
- Colorectal cancer: 900,000
- Liver cancer: 760,000
- Breast cancer: 670,000
- Stomach cancer: 660,000
The rankings for cancer mortality worldwide were nearly identical in 2020:
- Lung cancer: 1.8 million
- Colorectal: 935,000
- Liver: 830,000
- Stomach: 769,000
- Breast cancer: 685,000
In the United States, a similar pattern has emerged. The American Cancer Society (ACS) estimates lung cancer will claim more lives this year than any other cancer, even as screening and treatment advances have reduced mortality rates for some forms of the disease.
Around 135,000 Americans are expected to die from lung cancer in 2024 out of more than 600,000 projected cancer deaths. That’s more than breast, prostate, colorectal and pancreatic cancers combined.
Shifting Demographics Driving Up Cancer Diagnoses Among Young Adults
Perhaps most concerning in the U.S. cancer trends is that the average age of diagnosis is decreasing. In 1995, 61% of new cancer cases were in those 65 and over. But by 2020 that had dropped to 58% as diagnosis rates rose sharply among adults under 50.
In fact, those under 50 were the only age group that saw an increase in cancer diagnoses from 1995 to 2020, according to the ACS.
Certain cancers like colorectal are rising at an alarming rate in younger adults. Colorectal went from the 4th leading cancer killer in the late 1990s among those under 50 to the #1 cause of cancer death for younger men today. It’s now the 2nd leading cause for women under 50.
The ACS speculates that unfavorable lifestyle factors more prevalent in those born after 1950 are fueling the increase. These include obesity, heavy alcohol use, smoking, diets high in processed and red meats and low in fiber, and inactivity.
Italian researchers draw similar conclusions in a recent study, pinning rising colorectal cancer deaths in those 25-49 on obesity and alcohol consumption. They project bowel cancer mortality rates will rise for the first time ever this year among European millennials and Gen Xers.
The takeaway is clear: Our global community needs to double down on cancer prevention efforts and address widespread lifestyle risk factors like smoking, poor nutrition, inactivity and obesity.
We also must prioritize screening and early detection, particularly for cancers like colorectal that are striking at increasingly younger ages. Otherwise, the projected surge in new cancer cases and deaths will overwhelm healthcare systems and claim far too many lives unnecessarily.