"Our 11-year cohort study showed that it may be safe and feasible for men with elevated prostate-specific antigen (PSA) levels and prior negative biopsy to receive follow-up by prostate MRI and, potentially less frequently, in lieu of more invasive and potentially unpleasant follow-up prostate biopsies," Dr. Kirsteen Burton, a radiology resident at the University of Toronto, told AuntMinnie.com.
The researchers identified 541 prostate MRI exams that met their study criteria. The subjects had a median age of 63 years, and 132 men (24%) had a negative initial MRI; 73 (13%) of this group had a previous negative biopsy and median PSA of 10, and 59 (11%) had low-volume Gleason 6 disease and a median PSA of 6.
The results prompted the researchers to conclude that the risk of developing clinically significant disease over the median of 6.7 years was very low in men with a prior negative biopsy and negative MRI. Therefore, these patients could be followed less frequently.
"Our study results show that MRI offers an excellent negative predictive value for ruling out clinically significant prostate cancer -- that is, 96% of men who had a prior negative prostate biopsy and who subsequently received a prostate MRI had a true-negative prostate cancer result over a median follow-up period of just under seven years," Burton said.
