ExosomeDx in MRI-negative Men With High PSA

Magnetic resonance imaging (MRI) has become the current standard of care in risk stratifying men with an elevated Prostate-specific antigen (PSA) to determine who needs to undergo prostate biopsy, which is invasive and carries a 3-5% risk of serious infection. Recent data shows the negative predictive value of MRI to be only 77%, indicating that some men may inappropriately forego biopsy based on a negative MRI. Urinary exosomes can be captured and analyzed by the ExosomeDx (ExoDx) Prostate test, a urine based, gene signature derived from PCA3 (prostate cancer antigen 3) and ERG (erythroblast transformation-specific related gene), and SPDEF (SAM pointed domain-containing ETS transcription factor); ExoDx carries a 90% negative predictive value. The use of ExoDx test among patients with negative MRIs has the potential to improve the risk stratification of patients with an elevated PSA in a way that the Urologist can more accurately determine which patients need to undergo prostate biopsy. In doing so, the Urologist can better risk-stratify which patients should undergo prostate biopsy and be exposed to the associated potential risks, and also be more confident about the safety of foregoing biopsy in those patients with negative MRI and negative ExoDx test.