From biopsy to radical prostatectomy: determinants of pathological upgrading in prostate cancer

Abstract

Introduction: Discrepancy between the assessment of prostate cancer (PCa) grade based on biopsy and the final pathological findings after radical prostatectomy (RP) remains a significant challenge in preoperative risk stratification, particularly among patients diagnosed with low-risk disease. Accurate identification of patients at risk of pathological upgrading is crucial for appropriate treatment selection and reliable clinical counselling. To evaluate clinical, biopsy-related and multiparametric magnetic resonance imaging (mpMRI) – derived predictors of pathological upgrading in patients with PCa undergoing RP. Materials and methods: This retrospective, single-centre study included 82 consecutive men with PCa who underwent preoperative mpMRI followed by RP. Clinical data, prostate-specific antigen density (PSAD), and mpMRI features – including Prostate Imaging – Reporting and Data System (PI-RADS) category, lesion size, zonal location, and mpMRI-based tumour stage – were analysed. Pathological upgrading was defined as any increase in International Society of Urological Pathology (ISUP) Grade Group between biopsy and postoperative specimens. Univariable and multivariable logistic regression analyses were performed to identify predictors of upgrading. Results: Pathological upgrading was observed in 54 patients (65.85%), most commonly from ISUP Grade Group 1 to Grade Group 2. On univariable analysis, the presence of PI-RADS 5 lesions and PSAD ≥ 0.15 ng/mL/cm³ were significantly associated with upgrading (p < 0.05). In multivariable analysis, PI-RADS 5 remained the strongest independent predictor of upgrading (OR 7.997; 95% CI 1.363–46.901; p = 0.021), along with PSAD ≥ 0.15 ng/mL/cm³ (OR 4.721; 95% CI 1.522–14.644; p = 0.007). The model combining both parameters demonstrated moderate discriminative performance (area under the curve 0.77), with a sensitivity of 81.5% and a specificity of 57.1%. Conclusions: Pathological upgrading of PCa in patients with ISUP Grade Group 1 disease diagnosed by biopsy is a common phenomenon. PI-RADS 5 category and elevated PSA density represent independent risk factors for tumour underestimation on biopsy and may aid in identifying patients who require particular caution when being considered for active surveillance. Incorporation of these parameters into the decision-making process may improve individualised treatment strategies.