Outcomes of Serial Multiparametric Magnetic Resonance Imaging and Subsequent Biopsy in Men with Low-risk Prostate Cancer Managed with Active Surveillance

Eur Urol Focus. 2021 Jan;7(1):47-54. doi: 10.1016/j.euf.2019.05.011. Epub 2019 May 27.

Abstract

Background: Outcomes of serial multiparametric magnetic resonance imaging (mpMRI) and subsequent biopsy in monitoring prostate cancer (PCa) in men on active surveillance (AS) have not been defined clearly.

Objective: To determine whether changes in serial mpMRI can predict pathological upgrade among men with grade group (GG) 1 PCa managed with AS.

Design, setting, and participants: Retrospective analysis of men with GG1 on AS with at least two consecutive mpMRI examinations during 2012-2018 who underwent mpMRI/ultrasound fusion or systematic biopsies.

Outcome measurements and statistical analysis: Progression on serial mpMRI was evaluated as a predictor of pathological upgrading to GG≥2 on a follow-up biopsy using clinical, pathological, and imaging factors in binary logistic regression. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were determined.

Results and limitations: Of 122 patients, 29 men (23.8%) experienced pathological upgrade on the follow-up biopsy. Progression on mpMRI was not associated with pathological upgrade. The sensitivity, specificity, PPV, and NPV of mpMRI progression for predicting pathological upgrade were 41.3%, 54.8%, 22.2%, and 75%, respectively. Age (odds ratio [OR] 1.17, p=0.006), Prostate Imaging Reporting and Data System (PI-RADS) score on initial mpMRI (4-5 vs ≤3, OR 7.48, p=0.01), number of positive systematic cores (OR 1.84, p=0.03), number of positive targeted cores (OR 0.44, p=0.04), and maximum percent of targeted core tumor involvement (OR 1.04, p=0.01) were significantly associated with pathological upgrade.

Conclusions: We did not observe an association between mpMRI progression and pathological upgrade; however, a PI-RADS score of 4-5 on initial mpMRI was predictive of subsequent pathological progression. The continued use of systematic and fusion biopsies appears necessary due to risks of reclassification over time.

Patient summary: Progression on serial multiparametric magnetic resonance imaging during active surveillance (AS) is not associated with progression on the follow-up biopsy. Both systematic and fusion biopsies are necessary to sufficiently capture progression during AS.

Keywords: Active surveillance; Fusion biopsy; Multiparametric magnetic resonance imaging; Prostate cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biopsy / methods*
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Multiparametric Magnetic Resonance Imaging / methods*
  • Prostatic Neoplasms / diagnostic imaging*
  • Retrospective Studies
  • Watchful Waiting*