Identifying Risk Factors for MRI-Invisible Prostate Cancer in Patients Undergoing Transperineal Saturation Biopsy

Alberto Artiles Medina; Rafael Rodríguez-Patrón Rodríguez; Mercedes Ruiz Hernández; Marina Mata Alcaraz; Silvia García Barreras; Guillermo Fernández Conejo; Agustín Fraile Poblador; Enrique Sanz Mayayo; Francisco Javier Burgos Revilla

doi:10.2147/RRU.S323823

Identifying Risk Factors for MRI-Invisible Prostate Cancer in Patients Undergoing Transperineal Saturation Biopsy

Res Rep Urol. 2021 Sep 27:13:723-731. doi: 10.2147/RRU.S323823. eCollection 2021.

Authors

Alberto Artiles Medina¹, Rafael Rodríguez-Patrón Rodríguez¹, Mercedes Ruiz Hernández¹, Marina Mata Alcaraz¹, Silvia García Barreras¹, Guillermo Fernández Conejo¹, Agustín Fraile Poblador¹, Enrique Sanz Mayayo¹, Francisco Javier Burgos Revilla¹

Affiliation

¹ Department of Urology, Hospital Universitario Ramón y Cajal, University of Alcalá, Madrid, Spain.

Abstract

Purpose: Prostatic multi-parametric magnetic resonance imaging (mpMRI) has markedly improved the assessment of men with suspected prostate cancer (PCa). Nevertheless, as mpMRI exhibits a high negative predictive value, a negative MRI may represent a diagnostic dilemma. The aim of this study was to evaluate the incidence of positive transperineal saturation biopsy in men who have negative mpMRI and to analyse the factors associated with positive biopsy in this scenario.

Patients and methods: A retrospective study of men with normal mpMRI and suspicion of PCa who underwent saturation biopsy (≥20 cores) was carried out. A total of 580 patients underwent transperineal MRI/transrectal ultrasound fusion targeted biopsies or saturation prostate biopsies from January 2017 to September 2020. Of them, 73 had a pre-biopsy negative mpMRI (with Prostate Imaging - Reporting and Data System, PI-RADS, ≤2) and were included in this study. Demographics, clinical characteristics, data regarding biopsy results and potential predictive factors of positive saturation biopsy were collected. Univariate and multivariate logistic regression analyses were used to identify independent risk factors for MRI-invisible PCa.

Results: The detection rate of PCa with saturation biopsy in patients with negative MRI was 34/73 (46.58%). Out of 34 MRI-invisible prostate cancers detected, 12 (35.29%) were clinically significant PCa (csPCa) forms. Regarding factors of positive biopsy, in univariate analysis, the use of 5-alpha reductase inhibitors and free:total prostate-specific antigen (PSA) ratio were associated with the result of the saturation biopsy. In multivariate analysis, only an unfavourable free:total PSA ratio remained a risk factor (OR 11.03, CI95% 1.93-63.15, p=0.01). Furthermore, multivariate logistic analysis demonstrated that prostate volume >50mL significantly predicts the absence of csPCa on saturation biopsy (OR 0.11, 95% CI 0.01-0.94, p=0.04).

Conclusion: A free:total PSA ratio <20% is a risk factor for MRI-invisible PCa. Saturation biopsy could be considered in patients with suspected PCa, despite having a negative MRI.

Keywords: clinically significant prostate cancer; multi-parametric magnetic resonance imaging; negative MRI; prostate cancer; saturation biopsy.