A dad diagnosed with a cancerous brain tumour claims doctors repeatedly failed to pick up on it for 12 years.
Ben Jones, 37, from Merthyr Tydfil, said he had been for multiple brain scans at Prince Charles Hospital in 2010 and 2014, but doctors were unable to identify his tumour.
After years of suffering with pain, Ben began to have up to 30 seizures per day which led him to the decision to seek further medical help again this year.
Doctors finally recognised the growth on a scan at the hospital in July, Wales Online reports.
Ben was transferred to another hospital for specialist care where he was shockingly informed by doctors that his tumour had been detectable throughout all of his scans, since his first one 12 years ago.
The mass, which began on one part of the brain, has since spread to three parts of his brain and he will undergo major surgery in October to remove as much of it as possible.
However, doctors said it is highly likely the cancer will regrow and will have to be managed for the rest of his life.
In the meantime, Ben has been forced to give up his driver's licence and stop working as a railway site manager due to the tumour, seizures and the medication he is taking to reduce their frequency.
His best friend, Luke Davies, 37, has started a GoFundMe campaign to raise £6,000 for Ben and his family, so they can survive the next few months without his income.
Luke and a dozen other friends will be completing the Three Peaks Challenge in 24 hours to help raise the money.
Ben said he first had CT scans over two to three weeks at Prince Charles Hospital in 2010 after contracting bacterial meningitis.
Over the years before Ben was diagnosed, he took so many painkillers that Luke, who has been friends with him since their early teens, wondered if he was addicted to them.
The seizures that started more recently felt like "mini heart attacks" and left Ben unable to speak or use his left arm.
An MRI scan in Prince Charles Hospital on July 18 this year finally revealed the cause - news which Ben described as being "devastating".
He said: "I've known for a while that there has been something wrong, but I was not expecting it to be that."
Two weeks later, he was referred to Llandough Hospital, where doctors revisited the earlier scans and made the shocking revelation.
The 37-year-old said: "It was only then when they were showing me the scans that dated back to 2010 that I realised Prince Charles Hospital had missed it for all this time.
"It is visible. I could see it, my partner could see it as well."
The doctors at Llandough told Ben that doctors in Prince Charles might have interpreted the mass on the scan in 2014 as a "mini stroke", but Ben said there was no mention of this at the time either.
They also noted that doctors at Prince Charles Hospital left a referral note for Ben to have a MRI scan following the CF scan - but Ben says this was never mentioned to him and no appointment was ever made.
The cancer, which is stage 2, has grown considerably since 2014.
During the surgery in October, Ben will be awake and guiding the surgeons.
He will undergo radiotherapy after the surgery to further reduce the tumour's size.
Going forward, he will have to have an MRI scan every six month for the next ten years and will undergo more radio chemotherapy if the tumour grows.
Explaining how he might have to give up driving - and therefore his job - again in the future, he added: "I'm going to have to be assessed a year now from the operation, if everything is removed, in order to get my driver's licence back.
"If I have to have chemo or radiotherapy then, it's going to be another year from that date.
''So every time I have a treatment or something like that, it will keep setting me back a year. If I have a seizure, it'll go back a year."
Speaking of the effect his diagnosis had had on his family, Ben, who has three daughters aged 3, 11 and 15, said: "My family has been affected more than me. My parents are in bits. My partner is in bits."
He is in the process of getting financial help, but as this can take months Luke has set up the fundraiser to help in the meantime.
Luke said: "He hasn't long bought the house, there are a lot of bills to pay, and obviously the mortgage doesn't stop.
"Before the operation, I just want to try and get him some money so he can pay some bills and relax a little bit - so he goes into the operation with a clear mind and not having to worry about where the next bill payment is coming from."
On Friday, September 23, Luke and his friends will set off to begin the challenge.
Ben will also attempt to take part, and said it could be "the last physical thing I do for a while."
Speaking about his reaction to Ben's diagnosis, Luke said he thinks the fact the tumour was "negligence and incompetence" rather than "human error".
He continued: "It's just a nightmare, but we finally know that there is something wrong.
''I'm still trying to process it all. I'm just focussing on this challenge as a way of trying to deal with this."
You can donate to the fundraiser for Ben and his family here .
Prince Charles Hospital has been approached for comment.
Llandough Hospital said it was unable to comment on individual patient cases.
