Mp62-02 racial Disparities in Magnetic Resonance Imaging-Guided Biopsy for the Diagnosis of Prostate Cancer in the United States

Abstract

INTRODUCTION AND OBJECTIVE:There is ongoing discussion if the negative predictive value of mpMRI during active surveillance (AS) is sufficient to omit prostate biopsies. The next question is, what to do with patients having serial negative MRIs. The AUA guidelines only recommend to perform biopsies within 2 years after diagnosis and do not specify if MRI has a role in preventing unnecessary biopsies during active surveillance. The aim of this study is to add to the current evidence and to evaluate the predictive value of consecutive negative MRIs.METHODS: The PRIAS study is a multicenter prospective study providing an evidence-based recommendation on how to perform AS for patients with low-risk prostate cancer (PCa). The inclusion criteria and recommended follow up schedule are available on www. prias-project.org. All patients with consecutive negative MRIs during AS were included in the current analysis.RESULTS: In total, 180 men had two consecutively negative MRI (negMRI) during AS. The median time between the negMRI was 16 (interquartile range (IQR) 11-25) months. The median PSA at the time of the last negMRI was 6.0 (IQR 4.2-8.6) ng/ml. A total of 68 (38%) men underwent systematic biopsy (SBx) at the last negMRI showing no PCa in 29 patients (43%), PCa grade group (GG) 1 in 35 patients (51%) and PCa GG 2 in 4 patients (6%). Additionally, one patient underwent extraprotocollair PSMA PET/CT targeted prostate biopsies at the time of the last negMRI and was reclassified to PCa GG 3. Follow up data of 158 patients without reclassification at last negMRI who continued AS was available (Figure 1). Median follow up after last negMRI was 21 (IQR 10-34) months. 36 patients underwent additional biopsies of which 10 patients upgraded to GG2 and 3 patients upgraded to GG!3. All upgrading to GG!3 was detected by TBx on subsequent MRI.CONCLUSIONS: Patients with repeated negMRI during AS represent a low-risk group, however reclassification to GG2 cannot completely be excluded as, although very rare, reclassification to GG!3. This questions the need to perform SBx in these patients. Monitoring however, including repeat MRI should continue since progression on the long term cannot be excluded. It is reassuring that all upgrading to GG!3 was detected on MRI.