PI-RADS 3 lesions: Does the association of the lesion volume with the prostate-specific antigen density matter in the diagnosis of clinically significant prostate cancer?

Urol Oncol. 2021 Jul;39(7):431.e9-431.e13. doi: 10.1016/j.urolonc.2020.11.010. Epub 2020 Nov 19.

Abstract

Introduction: Currently, a new subclassification of the Pi-RADS 3 lesions and subgroups is being used: 3a (indolent or low-risk lesions with volume <0.5 ml) and 3b (significant or high-risk lesions with volume ≥0.5 ml). The prostate-specific antigen density (PSAd) has been identified as a diagnostic tool that helps to predict clinically significant prostate cancer (csCaP). The aim of this study is to evaluate the association of the volume of the Pi-RADS 3 lesions and the PSAd in the diagnosis of csCaP.

Material and methods: We conducted a retrospective study that included prostate biopsies performed using a transperineal approach and guided by ultrasound between 2015 and 2020. csCaP was defined as Gleason score ≥3 + 4. The population was divided into groups according to the Pi-RADS 3 subclassification and the PSAd value. We calculated sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) of 3b lesions for the detection of high-grade prostate cancer, alone and combined with PSAD groups.

Results: In total, 99 patients with Pi-RADS 3 lesions were included. Forty-three patients were in group 3a and 56, in 3b. Mean PSA was 7.28 ± 2.6 ng/ml. Pi-RADS 3a lesion did not present csCaP but 17.8% of Pi-RADS 3b lesion did. In group 3b with PSAd > 0.15, 62.5% presented csCaP. In those Pi-RADS 3b with PSAd ≤ 0.15, all biopsies were insignificant prostate cancer (isCaP) and 40 biopsies could have been avoided. Considering 3b as positive for csCaP detection, sensitivity was 100%, specificity 48.3%, NPV 17.8%, and PPV 100%. When adding PSAd to group 3b, sensitivity was 100%, specificity was 86.9%, NPV was 62.5%, PPV was 100%. In total, only the subgroup 3b with PSAd > 0.15 presented csCaP and 83.8% biopsies could be avoided.

Conclusions: In this series, the association of the volume of PIRADS 3 lesion and the PSAd improves specificity and PPV contributing to improve the management of csCaP.

Keywords: Lesion Volume; Pi-RADS; Prostate Cancer; prostate-specific antigen density.

MeSH terms

  • Aged
  • Data Systems
  • Humans
  • Male
  • Middle Aged
  • Prostate / diagnostic imaging
  • Prostate / pathology*
  • Prostate-Specific Antigen / blood*
  • Prostatic Neoplasms / blood*
  • Prostatic Neoplasms / diagnosis
  • Prostatic Neoplasms / diagnostic imaging
  • Prostatic Neoplasms / pathology*
  • Research Design
  • Retrospective Studies
  • Tumor Burden*

Substances

  • Prostate-Specific Antigen