‘Active’ man diagnosed with cancer reveals first symptoms that doctors originally dismissed as other condition

A man who went on to be diagnosed with cancer has insisted that persistence is key and urged people to really listen to their bodies, especially if they think there's something wrong.

A man named John has spoken about the process of being diagnosed with cancer and revealed that ChatGPT diagnosed him quicker than his own physicians did.

John has something called hereditary hemorrhagic telangiectasia (HHT).

Per Mayo Clinic, the condition causes atypical links between arteries and veins called arteriovenous malformations.

In some cases, HHT can cause a person to be more prone to developing polyps which are benign tissue growths that are commonly found in the colon, uterus, or nose.

John was aware of this, but he knew something wasn't quite right with his body when he began suffering with severe gastrointestinal pain after eating, which would then lead to vomiting as well.

John had started experiencing severe gastrointestinal pain (Getty Stock Image)

He thought it may have just been constipation at first or possible side effects of his HHT, but as time went on John 'knew something was wrong'.

"I actually thought that it was potentially a bowel obstruction," he told The Patient Story about when he first started experiencing symptoms in February 2025.

With his fears in mind he kept going back to his doctors and it was this persistence that 'paid off in the end'.

"They actually found a bowel obstruction and colon cancer," John continued to share, but this came after four trips to the emergency room over a two-month period.

Prior to his diagnosis and when the pain was at its worst, John said he felt 'completely hopeless' and had to switch to a liquid diet to manage his symptoms.

"I felt like none of my care team or physicians believed what I was telling them," John said.

When he eventually got the diagnosis he'd been pushing for, he said that he was relieved.

"Knowing it was cancer, that didn't even trouble me much," he said. "Just knowing that I had finally, you know, had an actual diagnosis— I'll be honest, I think my actual family and friends did much worse and were more emotionally troubled by it."

Because he was fit, healthy, and only in his 30s, doctors presumed his symptoms weren't from cancer (Getty Stock Image)

As to why he thinks no one believed him at first, he thinks his age and fitness played a part.

"I'm 38 years old, I'm physically a very fit guy and very active, [...] I go to the gym multiple times a week," John shared.

He continued to note that he'd lost as much as 30 pounds at one stage, but this didn't rush doctors to take his concerns more seriously and, because the type cancer he has is rare and he's only young, they thought it was improbable that that was causing his symptoms.

John has since undergone surgery and chemotherapy and, as of November 2025, pathology results came back negative for any cancer.

If you’ve been affected by any of these issues and want to speak to someone in confidence, contact the American Cancer Society on 1-800-227-2345 or via their live chat feature, available 24/7 every day of the year.