At the age of 20, while studying sports management and marketing at college, Sean Kukoleck’s life was suddenly interrupted by cancer. He experienced his first seizure, which led doctors to discover a large mass at the back of his brain. After a series of tests, specialists at Cincinnati Children’s Hospital diagnosed him with stage 4 high-grade glioma, a form of brain cancer known as glioblastoma multiforme. This aggressive and fast-growing tumor is often life-threatening.
“The diagnosis was overwhelming. My parents, friends, and professors couldn’t believe this was happening,” recalls Kukoleck.
He underwent surgery, proton radiotherapy, and chemotherapy, but later chose to participate in a clinical trial at UPMC in Pittsburgh. The trial was testing an immunotherapy drug called Keytruda (pembrolizumab), designed to enhance the immune system’s ability to fight cancer. For two years, Kukoleck received regular infusions every three weeks, along with frequent MRI scans.
During his treatment, Kukoleck and his family found support through the Cancer Research Institute, which provided valuable information and hope. “When we discovered the Cancer Research Institute, it changed my outlook. I became less fearful about the future,” says his mother, Nicki Kukoleck. “The breakthroughs in immunotherapy and the stories of other patients gave us hope that Sean had a real chance to survive.”
After completing two years of Keytruda treatment, Kukoleck entered full remission and now undergoes regular monitoring. He graduated in 2024 and is currently working in customer service with the Cleveland Guardians baseball team.
Key Takeaways
Early-onset cancers occur in adults aged 18-49, a group typically not associated with cancer, as most diagnoses are made later in life, usually in the 50s and 60s.
Common cancers on the rise in younger people include breast, colon, prostate, and cervical cancers. Lifestyle factors such as heavy alcohol consumption, sedentary behavior, poor diet, obesity, and tobacco use may contribute to the increase in early-onset cancers.
Early-onset cancers tend to be more aggressive and harder to treat.
Cancer screenings are now being recommended at younger ages, especially for those at higher risk or with a family history of cancer.
Rising Cancer Rates in Young Adults
Kukoleck is part of a growing trend of young adults diagnosed with cancer at younger ages. Over the past 30 years, the incidence of early-onset cancers—those diagnosed in adults between 18 and 49—has increased. The American Cancer Society reports that the rate of early-onset cancer diagnoses is rising by 1-2% annually.
A global study from 1990 to 2019 showed a 79% increase in early-onset cancer cases and a 27.7% rise in deaths. Cancers with the highest death rates include breast, lung, stomach, and colorectal cancers, while nasopharyngeal and prostate cancers have seen the fastest increases in incidence.
“It’s concerning to see more young adults diagnosed with cancer,” says Jill O’Donnell-Tormey, CEO of the Cancer Research Institute.
In a 2023 study published in JAMA, gastrointestinal cancers, including stomach, colon, rectal, and pancreatic cancers, were found to have the fastest-growing incidence rates in individuals under 50. Colorectal cancer, in particular, is now the leading cause of cancer death in people aged 20 to 49.
“Colorectal cancer is now the number one cause of cancer death in people ages 20 to 49,” says Dr. Ian Paquette, chief of colon and rectal surgery at the University of Cincinnati College of Medicine. “Ongoing research in the microbiome and gut bacteria balance may help us understand why this increase is occurring.”
Causes and Risk Factors for Early-Onset Cancer
Although the precise causes of rising cancer rates in younger adults remain unclear, researchers have identified several contributing factors:
Risk factors include heavy alcohol use, sedentary lifestyles, obesity, poor diet (including high intake of processed foods and red meats), tobacco use, and environmental exposures such as smoke or carcinogenic chemicals.
Body mass index (BMI) is a key factor; as the average BMI in Americans has risen, so too has the incidence of early-onset cancer.
However, doctors are often puzzled when young individuals who lead healthy lifestyles still develop cancer.
Case Study: Colon Cancer in a Healthy, Active Young Adult
Matt Stenger, 37, was a marathon runner and Ironman competitor who had never smoked or had any health concerns. But in 2022, just before his third child was born, Stenger began experiencing stomach pains. A colonoscopy revealed a tumor, which was diagnosed as stage 3 colon cancer.
“I thought it was a food allergy or gluten intolerance, not cancer,” Stenger says.
His treatment included genetic testing, which helped tailor a personalized care plan that combined surgery, chemotherapy, and immunotherapy. Today, Stenger is in remission and continues to run. “My blood work looks good, so I’m hopeful and back to training,” he adds.
Preventing Early-Onset Cancer
While there is no surefire way to prevent early-onset cancer, adopting healthy habits can reduce the risk:
Avoid tobacco: Quitting smoking lowers the risk of several cancers, including lung, mouth, throat, pancreas, and bladder cancers.
Exercise regularly: Physical activity helps maintain a healthy weight and reduces the risk of many cancers.
Get screened: With the rise of early-onset cancers, screening guidelines have been updated. For example, the American Cancer Society now recommends colorectal cancer screening beginning at age 45 for those at average risk.
Limit alcohol consumption: Reducing alcohol intake decreases the risk of breast, liver, and colon cancers.
Maintain a healthy weight: Eating a balanced diet with plenty of fruits, vegetables, whole grains, and lean proteins while limiting processed foods, red meats, and sugary items can help reduce cancer risk.
Special Care Needs for Younger Cancer Patients
Young cancer patients may face unique challenges, including the risk of long-term side effects like infertility, cardiovascular disease, and future cancers. Psychological support is also crucial, particularly after active treatment.
“Younger patients are more likely to face long-term side effects from aggressive treatments, such as ‘chemo brain’ and lifestyle changes post-surgery,” says O’Donnell-Tormey. “Managing these effects is key to improving their quality of life.”
The incidence of early-onset cancer is on the rise, particularly among people aged 20 to 49. While the exact causes remain unclear, lifestyle factors such as poor diet, obesity, and alcohol consumption are contributing to the trend. To lower cancer risk, young adults should focus on maintaining a healthy lifestyle, including regular exercise, a balanced diet, and timely screenings. Understanding and managing the unique challenges of early-onset cancer can help improve the quality of life and life expectancy for younger patients.