Impact of peri-prostatic fat measurements using MRI on the prediction of prostate cancer with transrectal ultrasound-guided biopsy

Abstract

Objectives: To estimate the impact of peri-prostatic fat (PPF) measurements using preoperative magnetic resonance imaging on the prediction of prostate cancer (PCa) with transrectal ultrasound-guided biopsy.

Patients and methods: We performed a retrospective 2-center study on 660 consecutive patients receiving transrectal ultrasound-guided biopsy-biopsy from June 2016 to October 2018. Pathologic and immunohistochemical characteristics were collected. PPF measurements including PPF area (PPFA) and PPFA to prostate area (PA) ratio (PPFA/PA) were assessed by preoperative staging magnetic resonance imaging. Clinical variables were correlated with Gleason score by using Spearman (ρ) correlation coefficients. Multivariable analysis was performed to identify independent predictors of PCa. The diagnostic performance was estimated using ROC curves.

Results: The Gleason score was significantly correlated with age (ρ = 0.114, P = 0.035), prostate-specific antigen (PSA) (ρ = 0.482, P < 0.001), PIRADS scoring (ρ = 0.403, P < 0.001) and PPFA/PA (ρ = 0.238, P < 0.001). Multivariate analysis revealed that PPFA/PA, age, digital rectal examination, family history of PCa, PSA, and PIRADS scoring were independently predictive of PCa. The ROC AUC to detect PCa or clinically significant PCa (CS-PCa; Gleason Score 3 + 4 or greater) improved with the addition of PPFA/PA (PCa: 0.93 vs. 0.89; CS-PCa: 0.92 vs. 0.90).

Conclusion: PPFA/PA is an independent predictor for PCa along with age, digital rectal examination, family history of PCa, PSA, and PIRADS scoring. PPF measurements especially PPFA/PA may help detect PCa or CS-PCa, thus helping improve PCa risk stratification and screening to avoid unnecessary biopsies.

Keywords: Biopsy; Magnetic resonance imaging; Peri-prostatic adipose tissue; Prostate cancer.