May Ashford, from Blackpool, was diagnosed with a brain tumour in 2010 after experiencing headaches and seizures.

Despite regular MRI scans at the Royal Preston Hospital showing that the tumour was growing, she was not offered surgery until five years later.

An investigation by the Parliamentary and Health Service Ombudsman (PHSO) said the treatment was too late as medical staff had failed to monitor the scan results properly.

Medical experts said Mrs Ashford should have been operated on at least three years earlier, before the tumour had time to grow and affect the surrounding area of the brain.

She tragically died aged 71 from a stroke following surgery.

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May's husband Alan, who brought the complaint to the Ombudsman, said his family have found no closure.

"My wife suffered horribly from the effects of the tumour for more than four years, and it was obvious to the family and myself when reading the scan reports that the monitoring of her tumour was highly suspect," he said.

""The tumour should have been removed before it came into contact with the carotid artery. The fact that it was not is a complete mystery to us."

Ombudsman Rob Behrens said this case once again emphasises the need for urgent improvements to imaging practices in the NHS.

"Our casework shows that sadly, Mrs Ashford is not the only person who lost her life because of mistakes related to scans and X-rays," he said.

"Timely analysis and reporting of scans is fundamental to the diagnosis and management of many health conditions. The sooner we see changes made; the fewer people we will see harmed by these entirely avoidable failings."

A Lancashire Teaching Hospitals spokesperson said: "As a Trust we acknowledge the findings of the Parliamentary and Health Service Ombudsman report relating to the care of Mrs Ashford and have offered our unreserved apologies to Mr Ashford.

"A detailed action plan was provided to Mr Ashford in November 2022 describing the measures that have taken place following the PHSO investigation to ensure that other patients and their families do not have a similar experience."

The Ombudsman's 2021 report on NHS imaging highlighted repeated failings like those found in May's case.

PHSO along with NHS England and the Royal College of Radiologists has urged the government to prioritise improvements to the way scans and X-rays are carried out and reported on.

The ombudsman said efforts to implement recommendations from the report have begun, but have been slow.