Men with negative MRI after negative biopsy do not harbour prostate cancer
A negative magnetic resonance imaging (MRI) following an initial negative MRI-guided biopsy is unlikely to lead to clinically significant prostate cancer and repeat biopsy, suggests a study. However, repeat MRI-guided biopsy is needed when lesions are seen on follow-up MRI.
A total of 2,716 men were identified, of whom 733 had a negative initial MRI-guided biopsy. Of these, 73 underwent follow-up MRI-guided biopsy. Participants had a median age of 64 years (interquartile range [IQR], 59–67) and prostate-specific antigen density of 0.12 ng/ml/cc (IQR, 0.08–0.17). Baseline Prostate Imaging Reporting and Data System (PI-RADS) score was ≥3 in 74 percent of men.
Seventeen of 73 participants (23 percent) were diagnosed with clinically significant prostate cancer at follow-up MRI-guided biopsy (median, 2.4 years; IQR, 1.3–3.6). Clinically significant prostate cancer was also found in 17 of 53 men (32 percent) when follow-up MRI showed a lesion (PI-RADS ≥3). However, cancer was not detected (0/10; p<0.01) when follow-up MRI was negative (PI-RADS <3).
Notably, more than half (54 percent) of men with PI-RADS 5 at follow-up MRI-guided biopsy were diagnosed with clinically significant prostate cancer.
This study included all men with a negative initial MRI-guided biopsy who underwent at least one more MRI-guided biopsy due to continued suspicion of clinically significant prostate cancer between September 2009 and July 2019. Biopsies were MRI-ultrasound fusion with targeted and systematic cores. The investigators targeted regions of interest from initial MRI and other new regions of interest at follow-up MRI-guided biopsy.
“MRI-guided biopsy which reveals no cancer may impart reassurance beyond that offered by ultrasound-guided biopsy. However, follow-up of men after a negative magnetic resonance imaging guided biopsy has been mostly by prostate-specific antigen testing and reports of follow-up tissue confirmation are few,” the investigators noted.