August 17, 2023
Cancer most commonly affects older adults, but cases among younger adults have been rising in recent years, according to new research.
Rates of early-onset cancer – when the disease develops before age 50 – increased by about 1% from 2010 to 2019, the study found. But these cancer rates particularly jumped among women and people in their 30s.
The study, published Wednesday by in JAMA Network Open, examined data from more than 560,000 people diagnosed with early-onset cancers. These cancers increased by about 19% among people ages 30-39, the most of any age demographic.
Early-onset cancers in women rose by 4.4% while declining by 4.9% among men. This disparity likely was driven by uptick in breast and uterus cancers.
Breast cancer was responsible for the highest number of early-onset cases, but gastrointestinal cancers grew at the fastest rate. Gastrointestinal cancers include those affecting the colon, rectum and pancreas. Previous research also has shown increases in early-onset cancers of the head and neck, kidneys and reproductive organs.
The reason for these increases is not clear, but researchers point to several possible factors, including higher rates of obesity, exposure to pollutants and other cancer-causing chemicals, and lifestyle factors like sleep patterns, lack of physical activity, drinking and smoking.
"This is a population that has had less focus in cancer research and their numbers are getting bigger, so it's important to do more research to understand why this is happening," said Dr. Paul Oberstein, director of the Gastrointestinal Medical Oncology Program at NYU Langone Health, told The Washington Post. He was not involved in the study.
The researchers said their study can be used to help develop "surveillance strategies and funding priorities."
The American Cancer Society recommends most people begin screenings for breast, prostate and colon cancers at age 45. Some women may want to begin breast cancer screenings earlier, and screenings for cervical cancer are advised to begin at age 25.
In 2022, an estimated 1.9 million new cancer cases were diagnosed, and there were more than 600,000 deaths related to cancer, according to the American Cancer Society. The median age of a cancer diagnosis in the U.S. is 66 years old, according to the National Cancer Institute.