The medical director of Scotland's largest cancer centre has apologised after overdoses of radiation were given to a 15-year-old girl.
Lisa Norris, from Girvan, in Ayrshire, was treated for a brain tumour at the Beatson Oncology Centre in Glasgow.
She was reportedly given 17 potentially deadly radiation overdoses.
Professor Alan Rodger said: "We are conscious of the distress that is being caused to Lisa and her family and we are very sorry this mistake happened."
He said: "Immediately upon discovering the overdose, we launched an internal investigation.
"This investigation established that no equipment failure was involved but that the overdose was the result of human error."
Prof Rodger said that the investigation had also confirmed that no other patient treatments were affected.
"The staff involved with this isolated incident are extremely distraught," he said.
The Scottish Executive health department is to conduct its own inquiry.
Lisa said she did not know what the future would hold for her.
"I could be brain damaged, I could be paralysed. Later in the future, like 10 or 15 years, I could not be here.
"Time will tell what is going to happen to me," she said.
The teenager said she was "very sore", with burns on the back of her neck and her ears.
"I am starting to blister and at night I can't sleep because I can't lie on my back, which I usually do," she added.
"Now I toss and turn because I lie on my side, and every time I toss and turn my mum or Andrew (her brother) has to get me back onto my side again."
Health Minister Andy Kerr said it was "a very regrettable incident".
Lisa Norris pictured before her illness (Picture: Daily Record)
He added: "Patient safety is at the heart of everything we do. We have sought assurances from NHS Greater Glasgow that no other patients have been put at risk - and they have given us that assurance.
"An investigation on behalf of ministers is already under way in conjunction with Greater Glasgow Health Board and radiation experts.
"The aims are to establish clearly what has happened and to identify the measures that will be taken to ensure that the causes of this incident cannot be repeated."
Dr Lesley Walker, director of cancer information at Cancer Research UK, said: "Because an overdose like this is extremely rare, it will be difficult for doctors to know exactly what lasting effect the overdose could have.
"It may be three months before they know exactly what has happened and which parts of her body may have been affected."
The Beatson is Scotland's largest cancer centre and the second-largest in the UK.
It sees 8,000 new patients each year and more than 15,000 courses of chemotherapy and 6,500 courses of radiotherapy are administered.
The centre is based on three sites in Glasgow.
The radiation overdose took place at the Western Infirmary.
Jenny Whelan, head of support group CancerBACUP Scotland, said that there were internal checks throughout radiotherapy treatment, given the potentially lethal consequences if it was wrongly administered.
"The machines are checked very regularly, there are physicists on-site that calibrate the machines and make sure that they're giving out the dose that has been prescribed," she said.
"Obviously something has gone badly wrong. We're all fallible but this is a very distressing outcome for a young woman in her situation.
"Incidents like this are incredibly rare but it is very frightening for everybody having radiotherapy treatment."