Introduction:

Prostate magnetic resonance imaging (MRI) has a well-established role prior to biopsy, yet up to 15% of men with a negative MRI may have high-grade prostate cancer (PCa) on subsequent systematic biopsy. There is currently little data to guide management for patients with a negative MRI followed by a negative systematic biopsy. We sought to characterize the long-term risk of high-grade PCa following both negative MRI and negative systematic biopsy.

Methods:

Using an institutionally maintained PCa database, we retrospectively identified patients who had negative MRI from January 2012 to December 2015. PIRADS version 1 was used for patients who had prostate MRI prior to February 2015, when our institution implemented PIRADS version 2. Patient charts were reviewed for a subsequent diagnosis of high-grade PCa, defined as Gleason grade 7 or greater on biopsy. For patients who had a negative biopsy following MRI, time-to-event analysis was performed to describe the long-term risk of high-grade PCa.

Results:

84 patients were identified as having a negative MRI during the study period. 62 patients subsequently had a negative standard transrectal 12 core systematic biopsy. None of these patients were diagnosed with high-grade PCa within the first three years following negative MRI (Figure 1). A total of 11.3% of patients were subsequently diagnosed with high-grade PCa. Median follow-up time was 71.2 months and 51.2% of patients had at least 5 years of available follow-up data. 

Conclusion:

There is an overall low long-term risk of high-grade PCa in patients who have had a negative MRI followed by a negative standard systematic biopsy. We propose that patients with persistent concern for PCa be reassessed at 3 years following both negative MRI and negative systemic biopsy.

Funding: N/A