Josh Vintner-Jackson was 29, active, and used to pushing his body hard. He ran marathons and worked at a startup in Austin. Then, in March 2020, a dull discomfort near his lower left hip began to linger.
At first, it sounded routine. Constipation, bloating, urgent care, laxatives. But a CT scan later showed a tumor blocking his colon, and doctors confirmed stage 3 colon cancer. His case is a reminder that youth can make serious symptoms look less urgent than they are.
A symptom that would not quit
By the end of May 2020, Vintner-Jackson had become severely constipated despite eating what he considered a healthy diet. After eight days without a bowel movement, he went to urgent care, where an X-ray showed a buildup in his colon.
His doctor thought it was stool, gave him laxatives, and told him it was “nothing to worry about.” The medication helped briefly. Then the constipation returned, and his stomach began to swell.
Constipation is common, and most cases are not cancer. But when a bowel change keeps coming back or comes with pain, it should not be waved away.
The scan that changed everything
By early July, his abdomen was swollen and painful. “I thought my stomach was going to implode. It had pushed out. I couldn’t sleep, I didn’t manage to sleep, I think, for 36 hours,” he said.
The next day, he walked about 1000 feet to the closest urgent care center, a short distance that felt exhausting. This time, the doctor sent him straight for a CT scan.
The scan showed a tumor blocking his colon. The next morning at 9 a.m., surgeons removed a golf ball-sized tumor, 15 inches of colon, and 15 lymph nodes. Seven of those lymph nodes were cancerous.
A colon anatomy model highlights the digestive system and the warning signs that can sometimes accompany colorectal cancer, including persistent constipation and abdominal discomfort.
Colon cancer is changing
Colon cancer begins in the colon, the part of the large intestine that helps turn digested food into stool. It can start as a small growth called a polyp, which may turn into cancer over time.
The American Cancer Society estimates that 158,850 new colorectal cancer cases will be diagnosed in the United States in 2026, with 55,230 deaths. Its 2026 report says cases are rising among adults ages 20 to 49, even as rates fall among adults 65 and older.
The same report says colorectal cancer is now the most common cancer-related death in people under 50. It also says about three out of four adults younger than 50 are diagnosed after the disease has already reached an advanced stage.
Why young adults get missed
Why is early-onset colon cancer rising? Researchers still do not have one clean answer.
The National Cancer Institute has pointed to diet, obesity, physical inactivity, environmental exposures, and changes in the gut microbiome, bacteria and other organisms inside the digestive system, as active areas of research.
There is also a human problem in the exam room. In a 2025 Colorectal Cancer Alliance survey of 1,000 nationally representative U.S. adults, 45 percent of people diagnosed with colorectal cancer before age 45 said a doctor had dismissed their stomach or bowel symptoms.
“Your age acts as a disguise when you walk in. You just assume you’re young and healthy. It’s probably a cold. Well, no, it might be something way more extreme,” Vintner-Jackson said.
Warning signs to take seriously
The Centers for Disease Control and Prevention lists possible symptoms that include blood in or on stool, diarrhea or constipation, a feeling that the bowel does not empty fully, stomach pain that does not go away, and unexplained weight loss.
Could these signs come from something less serious? Of course. But guessing is not the same as knowing.
For most adults at average risk, screening should begin soon after turning 45. People with a family history or other risk factors may need to start earlier. Ask questions, and keep asking if symptoms persist.
Living with the disease
Eight weeks after surgery, Vintner-Jackson began chemotherapy every two weeks for six months. After 12 rounds, tests showed no evidence of disease in his bloodwork. He thought he could go back to normal.
Nine months later, a blood test found a small trace of cancer cells, but doctors did not know where they were. After nearly a year of scans, they found the cancer had spread from his colon to his lungs. In October 2022, he was diagnosed with stage 4 cancer.
He moved back to the UK and has been on an almost constant cycle of chemotherapy, which has so far kept the cancer from advancing. He also trained as a life coach and started Chat Cancer, a support group for young people diagnosed with cancer.
A message for others
Vintner-Jackson is now 34. Some days he feels well. Other days, basic tasks are hard. His life is now “very much like gardening, going for dog walks, taking a very peaceful approach,” he said.
His warning is not to panic over every stomach issue. It is to notice patterns and speak up when something feels wrong. “If you get the diagnosis and you’re young, we are all out here and it is important to reach out,” he said.
The main report has been published by Business Insider.
