MRI, post-MRI biopsy drive decision making in newly diagnosed favourable-risk prostate cancer
Decision making in men with newly diagnosed favourable-risk prostate cancer is driven by magnetic resonance imaging (MRI) and post-MRI biopsy, according to a study, noting that post-MRI biopsy is a stronger driver of decision making than MRI alone.
“This was demonstrated by the >90 percent of men with reassuring post-MRI biopsies who elected active surveillance regardless of MRI results,” the authors said.
A total of 1,461 men with favourable-risk prostate cancer were included. Of these, 1,223 (84 percent) did not undergo MRI, 157 (11 percent) underwent MRI alone, and 81 (6 percent) underwent MRI and post-MRI biopsy.
There were more men with reassuring findings than those with nonreassuring or MRI findings who elected active surveillance (74 percent vs 35 percent and 42 percent, respectively) among patients who underwent MRI alone.
Furthermore, men with reassuring post-MRI biopsy had the highest rate of active surveillance regardless of whether MRI was reassuring or nonreassuring (93 percent and 96 percent, respectively).
The authors reviewed the records of men with newly diagnosed favourable risk prostate cancer in the Michigan Urological Surgery Improvement Collaborative. These men were classified into three groups following diagnostic biopsy: group 1, no MRI; group 2, MRI only; group 3, MRI/post-MRI biopsy.
MRI results were deemed reassuring (Prostate Imaging Reporting and Data System [PI-RADS] ≤3) or nonreassuring (PI-RADS ≥4) for purposes of counselling and shared decision making.
Additionally, if the diagnostic biopsy was grade group (GG) 1, post-MRI biopsy results were considered nonreassuring should there be any amount of GG ≥2. If the diagnostic biopsy was GG 2, post-MRI biopsy results were deemed nonreassuring if more than three cores were GG 2, or there was >50-percent GG2 in any individual core or any volume of GG ≥3.