PURPOSE

We investigated how magnetic resonance imaging and post-magnetic resonance imaging biopsy impact decision making in men considering active surveillance.

MATERIALS AND METHODS

We reviewed the records of men in the Michigan Urological Surgery Improvement Collaborative with newly diagnosed favorable risk prostate cancer. Following diagnostic biopsy the men were classified into 3 groups, including group 1-no magnetic resonance imaging, group 2-magnetic resonance imaging only and group 3-magnetic resonance imaging/post-magnetic resonance imaging biopsy. For the purposes of counseling and shared decision making magnetic resonance imaging results were deemed reassuring (PI-RADS™ [Prostate Imaging Reporting and Data System] 3 or less) or nonreassuring (PI-RADS 4 or greater). Similarly, if the diagnostic biopsy was GG (Grade Group) 1, post-magnetic resonance imaging biopsy results were deemed nonreassuring if there was any amount of GG 2 or greater. If the diagnostic biopsy was GG 2, post-magnetic resonance imaging biopsy results were deemed nonreassuring if more than 3 cores were GG 2, or there was more than 50% GG 2 in any individual core or any volume of GG 3 or greater.

RESULTS

Of 1,461 men with favorable risk prostate cancer 1,223 (84%) did not undergo magnetic resonance imaging, 157 (11%) underwent magnetic resonance imaging alone and 81 (6%) underwent magnetic resonance imaging and post-magnetic resonance imaging biopsy. Of the men who underwent magnetic resonance imaging alone more with reassuring findings elected active surveillance than men with nonreassuring or magnetic resonance imaging findings (74% vs 35% and 42%, respectively). The highest rate of active surveillance was noted in men with reassuring post-magnetic resonance imaging biopsy regardless of whether magnetic resonance imaging was reassuring or nonreassuring (93% and 96%, respectively).

CONCLUSIONS

Magnetic resonance imaging and post-magnetic resonance imaging biopsy drive decision making in men with newly diagnosed, favorable risk prostate cancer. Post-magnetic resonance imaging biopsy is a stronger driver of decision making than magnetic resonance imaging alone. This was demonstrated by the more than 90% of men with reassuring post-magnetic resonance imaging biopsies who elected active surveillance regardless of magnetic resonance imaging results.