MRI scans on men with suspected prostate cancer could help avoid unnecessary biopsy

According to a study published in The Lancet, men with suspected prostate cancer who undergo MRI first could improve diagnosis and avoid unnecessary biopsy.

More than 100,000 prostate biopsies are conducted in the U.K. each year, with another million in Europe. Many of them are unnecessary, because the prostate specific antigen (PSA) test is not always accurate. Data suggests that one in four men could avoid a biopsy.

Lead author of the study, Hashim Ahmed states, “Prostate cancer has aggressive and harmless forms. Our current biopsy test can be inaccurate because the tissue samples are taken at random. This means it cannot confirm whether a cancer is aggressive or not and can miss aggressive cancers that are actually there. Because of this some men with no cancer or harmless cancers are sometimes given the wrong diagnosis and are then treated even though this offers no survival benefit and can often cause side effects. On top of these errors in diagnosis, the current biopsy test can cause side effects such as bleeding, pain and serious infections.”

Multi-parametric MRI (MP-MRI) scans are able to show a cancer’s size, cells and bloodstream matter, thus helping to diagnose the cancer as aggressive or harmless.

Some 576 men with suspected prostate cancer underwent an MP-MRI scan as well as a template prostate mapping (TPM) biopsy and transrectal ultrasound-guided (TRUS) biopsy.

The TPM biopsy was able to detect that less than 50 percent of the men had an aggressive cancer. The MP-MRI scan identified 93 percent of the aggressive cancers, whereas the TRUS biopsy only diagnosed 48 percent. In addition, nine out of ten men with negative results on the MP-MRI scan had no cancer or a harmless cancer.

"While combining the two tests gives better results than biopsy alone, this is still not 100 percent accurate so it would be important that men would still be monitored after their MP-MRI scan. Biopsies will still be needed if an MP-MRI scan shows suspected cancer too, but the scan could help to guide the biopsy so that fewer and better biopsies are taken,” wrote Ahmed.