A permanently hungry man, who would eat himself to death if not supervised 24 hours a day, is to receive £400,000 compensation from the NHS it emerged yesterday.

Daniel Williams, 24, was left with brain damage when doctors at Bristol Children's hospital, then run by the former Avon health authority, did not spot a tumour until he was 12 years old, said his mother, Tracey Williams, yesterday.

But she said she was still angry that no one had admitted liability or been brought to justice for the alleged mistake.

"I knew from the age of five that something was wrong with Daniel," she said. "When he was finally diagnosed as having a tumour in 1991, a lot of damage had already been done to his brain. Daniel needs 24-hour supervision because he's permanently hungry and if left alone he would just eat himself to death."

Mrs Williams, from Bristol, said the out-of-court settlement would help fund treatment for her son, who lives most of the time at a specialist hospital in Nottingham but goes home for some weekends.

"If this had been spotted earlier he would now have a better quality of life," she said.

A spokeswoman for the new Avon, Gloucestershire and Wiltshire strategic health authority said it had not denied liability for Daniel's condition.