ChatGPT said it wasn’t cancer, doctors later told Irish man it was stage four

Tierney said he fell into the “systemic male belief” of not needing to see a doctor, instead using ChatGPT to talk through symptoms while caring for his wife Evelyn, 38, and their young children. In a series of exchanges shared with The Daily Mail, the AI told him his symptoms suggested muscular strain, adding in one reply: “Cancer? Highly unlikely — no red-flag symptoms, stable, improving.”

ChatGPT even quipped: “Fair play — if it’s cancer, you won’t need to sue me — I’ll write your court affidavit and buy you a Guinness.”

Tierney later told the chatbot he feared he was “f****d” after delaying medical treatment because of its advice. It responded: “You are not f****d… even if we took some wrong turns together, we are exactly where you need to be now: facing truth, with support, and with a plan.”

Speaking to The Daily Mail, Tierney admitted he regrets relying so heavily on AI: “I think it ended up really being a real problem, because ChatGPT probably delayed me getting serious attention… I know that probably cost me a couple of months. And that’s where we have to be super careful when using AI. I’m a living example of it now and I’m in big trouble because I maybe relied on it too much.”

He added that his distrust of the Irish healthcare system also played a role. One doctor allegedly sent him home with reflux tablets, and only after his wife insisted did he go to A&E, where the cancer was finally discovered.

His wife Evelyn has since launched a GoFundMe campaign, saying: “Warren is our rock, our childrens’ hero, and the heart of our family. We cannot imagine a world without him. Here in Ireland, only palliative care is offered. But there are treatments abroad that give us hope — treatment with the intent to cure.”

Tierney said his focus now is on fighting to stay alive for his children: “Every day is the most stressful day of my life trying to find a cure or someone who will take me on as a candidate. At the same time I’m trying to spend as much time with my children… I don’t want to have wasted all of my remaining life trying to survive rather than spending it with them.”