October is the month of pink ribbons, dedicated to breast cancer awareness. This disease remains one of the most common types in women, accounting for about one in three of all new female cancers each year, according to the American Cancer Society (ACS). Not only is the number of breast cancer diagnoses growing, but the disease, in general, is affecting more of our youth. While we celebrate awareness this spooky month, let’s also look at why so many young people are being diagnosed with cancer.
Women, especially, are being hit with higher cancer rates. In fact, females under 50 are more likely to develop the disease than men of the same age. A report by the American Cancer Society found that cancer rates for young women have “increased from 51% higher than men in 2002 to 82% higher in 2021.” Breast cancer is driving these numbers up, increasing 1% each year from 2012 through 2021. In women under 50, it has increased 1.4% per year, according to the report. Some of the possible risk factors include being overweight, having children later in life, and having fewer childbirths.
For decades, clinicians viewed cancer largely as something to watch for in middle age or beyond. But over the past few decades, several cancers have begun appearing more frequently at younger ages. One of the most well-documented is early-onset colorectal cancer. A review of 81 studies involving nearly 25 million patients under 50 showed that younger adults often present with more advanced disease, in part because symptoms are dismissed or diagnosis is delayed.
“We know rates are increasing in young people, but it’s alarming to see how rapidly the whole patient population is shifting younger, despite shrinking numbers in the overall population,” said Rebecca Siegel, senior scientific director, surveillance research at the American Cancer Society, and lead author of one report.
Colorectal cancer (CRC) “is the third most commonly diagnosed cancer and the third leading cause of cancer death in both men and women in the U.S.,” according to ACS. Furthermore:
“[R]esearchers showed the proportion of individuals in the United States diagnosed with advanced-stage colorectal cancer (CRC) increased from 52% in the mid-2000s to 60% in 2019. In addition, diagnoses of people under 55 years of age doubled from 11% (1 in 10) in 1995 to 20% (1 in 5) in 2019. Overall, in 2023, an estimated 153,020 people will be diagnosed with CRC in the U.S., and 52,550 people will die from the disease.”
Young folks being diagnosed with CRC are happening more frequently. “I remember seeing the first wave of these patients, if you will, and it just seemed like an anomaly, like one-offs — and it was awful,” said Sonia Ramamoorthy, MD, FACS, chief of colorectal surgery at the University of California San Diego and president of the American Society of Colon and Rectal Surgeons. “But this phenomenon started to become more and more commonplace. And I remember saying to our genetics counselor, ‘What is going on? We’re seeing so many more rectal cancers in young patients — what is happening here?’”
So what is causing this? Diet and ultra-processed foods are likely candidates, of course. As is obesity. Biological aging is another contributor. Some young adults who develop cancer show biomarkers consistent with bodies that are biologically older than their chronological age. For instance, a 2024 study analyzing data from the UK Biobank indicated that individuals who developed early-onset cancers tended to show signs of cellular aging – such as elevated inflammation markers or altered blood biomarkers – years before diagnosis. This raises the possibility that exposures accumulating over life – some starting in childhood – may prematurely age tissues and increase their vulnerability to cancer.
Also baffling professionals is that many of the young patients with colorectal cancer don’t have the traditional risk factors. They might not be obese or have it run in the family, for example. Another problem is that cancer isn’t usually associated with youth. In younger people, symptoms are often overlooked or dismissed as something else. One hallmark of cancer in younger people is that symptoms are often overlooked or misattributed. Those in their 30s experiencing rectal bleeding, persistent abdominal pain, or unexplained weight loss are unlikely to think: “Maybe I have colon cancer.” Instead, they may assume it’s hemorrhoids, stress, diet, or a temporary gut bug. As a result, diagnosis can be delayed by months, ACS explained.
What does 2025 hold for breast cancer in the United States? According to ACS:
While October’s breast cancer messaging remains vital, we can also use this month as a reminder that cancer does not always wait until later life.