Systematic biopsy urged in patients with negative MRI

10 Oct 2020
Systematic biopsy urged in patients with negative MRI

Magnetic resonance imaging (MRI) is vital for the detection of high-grade cancer, and a recent study further adds to this data by recommending systematic biopsy in patients with negative MRI and the inclusion of systematic biopsy in those with positive MRI.

Men enrolled in Canary Prostate Active Surveillance Study with Gleason grade group <2 and who underwent biopsy within 12 months of multiparametric MRI were included in this analysis. Biopsy reclassification to Gleason grade group 2 was the primary outcome.

The authors assessed the performance of MRI Prostate Imaging–Reporting and Data System (PI-RADS) score and clinical factors. They also fitted multivariable logistic regression models with MRI and clinical factors and used these models to perform receiver operating curve analyses.

Overall, 361 participants with 395 prostate MRI studies, with a median follow-up of 4.1 years (interquartile range, 2.0-7.6), were included. One hundred eight (27 percent) biopsies demonstrated reclassification.

Defining positive MRI as PI-RADS 3-5, the negative and positive predictive values for detecting Gleason grade group 2 cancer was 83 percent (95 percent confidence interval [CI], 76–90) and 31 percent (95 percent CI, 26–37), respectively.

In a multivariable model, PI-RADS significantly correlated with reclassification (PI-RADS 5 vs 1 and 2; odds ratio, 2.71, 95 percent CI, 1.21–6.17; p=0.016), but it did not improve upon a model with only clinical factors (AUC, 0.768 vs 0.762).

In 194 fusion biopsies, higher grade cancer was detected in targeted cores in 21 instances (11 percent). On the other hand, 24 (13 percent) had higher grade cancer in the systematic cores.

J Urol 2020;204:701-706