A team of urologists, surgeons, radiologists and pathologists studied 31 Princess Margaret Hospital (PMH) patients who had positive biopsy results and tumours on top of their prostate as shown on magnetic resonance imaging (MRI). They found that MRI was able to help diagnose hidden prostate tumours 87% of the time.

Researchers at the University of Toronto and PMH in their study demonstrates that MRI is the best tool to reveal tumours.

The research, published online on October 8, 2009 in the British Journal of Urology International (BJU 8938).

“Our findings identify a specific high-risk group whose tumours are difficult to diagnose because of location. These men benefit from MRI, which guides the biopsy procedure with a high degree of accuracy,” said author Dr. Nathan Lawrentschuk, urologic oncology fellow, PMH cancer program, University Health Network. “The research team calls the clinical presentation of elevated PSA and repeated negative biopsy results ‘prostate evasive anterior tumour syndrome’ (PEATS).”

“Knowing about PEATS may also be important for men already on ‘active surveillance’ – patients with slow-growing prostate cancer who are being regularly monitored through PSA testing and biopsy. Every man does not need an MRI, but knowing about PEATS will help us identify those who do,” said principal investigator Neil Fleshner, a professor of Surgery at University of Toronto, Love Chair in Prostate Cancer Prevention Research and head of the Division of Urology, Princess Margaret Hospital.