PRostate Evaluation for Clinically Important Disease: MRI vs Standard Evaluation Procedures

The standard pathway for prostate cancer diagnosis is trans-rectal ultrasound guided (TRUS) biopsy of the prostate following an elevated PSA. TRUS guidance is performed primarily for anatomic guidance as the ultrasound poorly discriminates between cancerous and non-cancerous tissue. TRUS guided prostate biopsies are concentrated in areas of the peripheral zone, thought to harbor the majority of cancer. An alternative pathway for prostate cancer diagnosis in men with elevated PSA is to perform multi-parametric magnetic resonance imaging (MPMRI) to localize cancer. This information is used to direct a subsequent biopsy, known as an MRI-targeted biopsy. MRI-targeted biopsy has been shown in preliminary studies to detect a similar or greater amount of clinically significant cancer than systematic TRUS guided biopsy and has several other potential advantages including: the ability to differentiate between clinically significant and insignificant cancer, reducing unnecessary biopsy and fewer numbers of biopsy cores, reducing biopsy-related side-effects. A 'clinically insignificant cancer' is cancer that is unlikely to progress or to affect an individual's life expectancy and therefore does not warrant treatment. However when diagnosed with low grade cancer that is likely to be insignificant, a large proportion of subjects request treatment in case a more significant cancer is present. A challenge in this area is that subjects are typically not aware that their cancer is clinically insignificant, and often view the early diagnosis and aggressive treatment they have been subjected to as life-saving. A prostate cancer detection procedure that differentiates clinically significant cancer from clinically insignificant cancer is therefore a major unmet need. The potential implications of this trial include: * A redefinition of the prostate cancer diagnostic pathway; * A reduction in the number of subjects undergoing prostate biopsy; * A reduction in the number of biopsy cores taken per subject; * A reduction in biopsy-related adverse events including sepsis and pain; * A reduction in the over-diagnosis of clinically insignificant prostate cancer; * A reduction in the economic burden of diagnosing and treating prostate cancer.