The Scottish Mail on Sunday
Scan that helps men avoid risky prostate biopsy
MEN with suspected prostate cancer could be spared painful and risky needle biopsy tests thanks to a new scanning technique that can detect tumours just as accurately, a new study has found.
Currently, if doctors believe a man is suffering symptoms that indicate the disease, he will first be offered a blood test that looks for raised levels of prostate specific antigen (PSA), a protein produced by the prostate gland.
Although a higher-than-normal PSA level may be caused by cancer, it can also be the result of other benign conditions.
However, about 150,000 men a year will then have a transrectal ultrasound (TRUS) biopsy, where ten to 12 small tissue samples are taken from the prostate via the rectum using a needle.
But this causes pain, which in some men can last for weeks. It can also cause bleeding in the urine or semen – and up to one in three men are treated for an infection afterwards.
A less invasive approach is being recommended after the Prostate MRI Imaging Study (PROMIS), in which 740 men with blood tests that indicated prostate cancer were offered a special type of MRI scan.
A quarter of the men were either diagnosed with cancer or given the all-clear, meaning they could safely avoid a biopsy.
For those men who did still need a biopsy, just having a detailed scan of the prostate in advance meant that doctors could take samples from the suspect areas and improve accuracy.
Professor Raj Persad, consultant urologist at North Bristol NHS Trust who took part in the study at Southmead Hospital, said: ‘Accurate treatment of prostate cancer depends on accurate diagnosis, but PSA levels can vary widely and are affected by prostate size, age, recent surgery, how recently a man has had sex, and even cycling, so they are a very inaccurate guide.
‘And a TRUS biopsy effectively takes tissue samples at random, and so may miss a cancer entirely so we may give a patient the all-clear when they actually have a clinically significant cancer.’
Prostate cancer is the most common cancer among men in the UK, with 47,000 new cases diagnosed annually. About 11,000 men die of the disease.
However, thanks to advances in treatment, the outlook is generally good. Around 84 per cent of men with prostate cancer survive for more than ten years after diagnosis.
Nationally, about half of men who are thought to have prostate cancer have the specialist scan –multi-parametric magnetic resonance imaging, or MP-MRI – before a biopsy.
While most major hospitals now have the right kind of scanning facilities, practice varies widely. Some offer this to all patients before biopsy, some to very few.
Tim Dudderidge, consultant urological surgeon at Southampton Hospital, said: ‘Around a quarter of men could be spared a biopsy by proper scanning. Scans are being offered in a haphazard way, and we need a streamlined national system to spare men unnecessary biopsies.’