Reconciling Discordance Between Prostate Biopsy Histology and Magnetic Resonance Imaging Suspicion - Implementation of a Quality Improvement Protocol of Imaging Re-review and Reverse-fusion Target Analysis.

There is uncertainty with how to proceed when targeted prostate biopsy of suspicious multiparametric magnetic resonance imaging (mpMRI) lesions return without clinically significant prostate cancer (csPCa). While possible, there are error sources that could contribute to such discordance including the mpMRI read, mpMRI-ultrasound fusion, biopsy technique, and histologic classification. Consequences are potentially significant; mistakenly missing csPCa can lead to delays in curative treatment. Conversely, in cases of incorrect mpMRI interpretation, the patient may be subjected to unnecessary workup/burden. At our institution, we implemented a quality improvement (QI) initiative triggered after a discordant case occurs. This multidisciplinary review process incorporates mpMRI re-review and assessment of accurate lesion-sampling, termed "reverse-fusion." Herein, we describe the protocol, present sample cases, and discuss clinical implications.