An investigation is under way into claims a cancer patient was told he could not book a hospital appointment because records showed he was dead.
Alan Campbell, of Blackburn, Lancashire, said he was given the news by an NHS telephone operator.
The 63-year-old said he was told "deceased" was written on his records and he could not make a booking.
NHS Blackburn with Darwen Teaching Care Trust Plus apologised for "distress caused to the patient".
Janice Horrocks, an executive director at the trust, added: "We are currently holding a detailed investigation into the circumstances surrounding this case and are working with the patient to secure an appointment.
"We would like to reassure patients that using the Choose and Book system remains the fastest route to getting the quickest and most convenient hospital appointment for the care that you need.
"It allows you to choose the hospital, time and date of your appointment."