Irish father says ChatGPT told him cancer was highly unlikely, delaying care before a stage-four oesophageal cancer diagnosis
Warren Tierney, 37, a former psychologist from County Kerry, Ireland, told the Daily Mail that in 2025 he put a worsening sore throat and difficulty swallowing to ChatGPT over several weeks instead of seeing a doctor. Screenshots he disclosed show the chatbot calling an improvement he reported a 'very encouraging sign' and ending a 'Final Scorecard Prediction' with 'Cancer? Highly unlikely'. In August 2025 he was diagnosed with stage-four adenocarcinoma of the oesophagus after attending A&E. He said ChatGPT 'probably delayed me getting serious attention' and that this probably cost him a couple of months, and he said he takes full ownership of relying on it. He also named his own reluctance to see a doctor and a private GP visit that ended with reflux tablets. No source establishes that the delay changed his prognosis. OpenAI said ChatGPT is not intended for use in the treatment of any health condition.
AI involvement reported · Causal attribution alleged · 4 sources, 1 underlying account · Added 12/09/2026