An advanced type of body scan could help doctors decide when a man with slow-growing prostate cancer needs treatment.
Many men diagnosed with early prostate cancer that is not immediately life threatening undergo “active surveillance”.
Doctors monitor their condition with biopsies and blood tests and only start aggressive treatment if the tumour starts to grow more quickly.
The new technique, called diffusion-weighted magnetic resonance imaging (MRI), provides a more patient-friendly and reliable method of monitoring prostate cancer, scientists believe.
In the pilot study, 50 patients were scanned at the time of their initial diagnosis and given another examination two years later.
By the time of their follow-up appointment, 17 of the men had received required treatment while 33 remained under active surveillance.
The team found the diffusion-weighted readings fell between the two scans in men who progressed to treatment, but remained constant in those who did not.
Study leader Professor Nandita deSouza, from the Institute of Cancer Research, based in Sutton, Surrey, and London, said: “Diffusion-weighted MRI has a lot of potential for monitoring patients under active surveillance, as the scans clearly showed which men’s cancers were progressing.
“If the technique continues to show promise in larger-scale studies, it could one day save men under active surveillance from the discomfort and potential complications of regular biopsies.”
The findings are published in the British Journal of Radiology.
Recent figures show the proportion of men opting for active surveillance rose from zero to 39% between 2002 and 2006.
It has become more common since the National Institute for health and Clinical Excellence (Nice), which looks at the cost-effectiveness of new drugs and procedures, allowed it to become a standard treatment option in 2008.