The UK does not have enough radiologists to meet demand, according to a new report.
Nearly all radiology departments responding to a survey said they were unable to carry out enough tests with their staff's contracted hours. On average nearly 1 in 10 posts have been unfilled over the last 6 years.
Sara Bainbridge, policy manager at Cancer Research UK, said that patients could be missing out on timely scan results to tell them if they have cancer.
The report, from the Royal College of Radiologists, is based on a 2016 census of NHS radiology departments across the UK.
Radiologists are doctors who specialise in interpreting images from x-rays, MRI and CT scans. The results of these scans are vital in diagnosing many diseases, including cancer. But delays in diagnosis can contribute to delays in treatment.
The report shows that while the consultant radiology workforce has increased by 3% since 2010, this hasn't kept pace with increased demand placed on radiology services. The number of CT and MRI scans performed in UK hospitals increased by around 10% each year from 2013-2016.
Dr Nicola Strickland, president of The Royal College of Radiologists, criticised the Government for failing to invest in trainee radiologists.
"[The Government] is content to waste millions of pounds of NHS funds paying for scans and x-rays to be reported out-of-hours, as well as paying for expensive locum consultants just to keep hospital imaging departments afloat," she said.
"Without more radiologists, more patients will miss out on vital new interventional procedures, and they will wait even longer for diagnoses of cancer and serious diseases."
According to the report the UK has 7.5 radiologists per 100,000 people, the third lowest of 31 European countries. At least 1 in 4 consultant radiologists is from outside the UK.
The number of unfilled consultant radiologist posts varies largely across the country, ranging from 4 in 100 in London to 20 in 100 in Northern Ireland. On average 8.5 in 100 posts are unfilled in the UK.
"The only lasting way to sort out this problem is to invest now in training many more radiologists, which will more than pay for itself in the near future," said Strickland.
Bainbridge said the census gives further proof of how the shortages in staff are impacting on tests that diagnose cancer across the country.
"We're pleased that Health Education England, who are in charge of education and training of radiologists in England, are developing a workforce plan," she said. "This is an area where progress has been slow since the cancer strategy was published over two years ago.
"We're calling on the Government to make sure this plan is fully funded to address staff shortages and enable the NHS to diagnose more cancers early."
Almost all UK radiology departments (97%) were unable to meet demand for tests using the contracted hours of their staff, according to the report.
More than 9 in 10 said they paid consultants overtime in attempts to tackle demand. Nearly 8 in 10 said they outsourced work to private companies, and more than half employed temporary staff.
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Clinical Radiology UK workforce census 2016 Report, Royal College of Radiologists: www.rcr.ac.uk/posts/latest-wor … gist-staffing-crisis