Prostate Volume Index Is Able to Differentiate between Prostatic Chronic Inflammation and Prostate Cancer in Patients with Normal Digital Rectal Examination and Prostate-Specific Antigen Values <10 ng/mL: Results of 564 Biopsy Naïve Cases

Introduction: To assess the association of prostate volume index (PVI), defined as the ratio of the central transition zone volume to the peripheral zone volume, and prostatic chronic inflammation (PCI) as predictors of prostate cancer (PCA) risk in patients presenting with normal digital rectal exam and prostate-specific antigen (PSA) ≤10 ng/mL at baseline random biopsies. Methods: We evaluated patients with a negative digital rectal examination (DRE) and a PSA ≤10 ng/mL who underwent initial baseline prostate biopsy from 2010 to 2017. Parameters evaluated included age, PSA, total prostate volume (TPV), PSA density (PSAD), PVI and PCI. All patients underwent 14 core trans-perineal standard biopsies. The association of factors with the risk of PCA was evaluated by logistic regression analysis, utilizing 2 multivariate models: model I included age, TPV, PVI and PCI; model II included age, PSAD, PVI and PC. Results: Overall, 564 Caucasian patients were included. PCA and PCI were detected in 242 (42.9%) and 129 (22.9%) cases respectively. In patients with PCA, the median PVI was 0.83 (interquartile range [IQR] 0.62-1.04). In patients with PCI, the median PVI was 1.12 (IQR 0.81-1.47). In model I, age (OR 1.080) TPV (OR 0.961), PVI (OR 0.517) and PCI (OR 0.249) were associated with PCA risk. In model II, the age (OR 1.074), PSAD (OR 3.080), PVI (OR 0.361) and PCI (OR 0.221) were associated with PCA risk. Conclusions: Higher PVI and PCI predicted decreased PCA risk in patients presenting with normal DRE, and a PSA ≤10ng/mL at baseline random biopsy. In this subset of patients, PVI is able to differentiate patients with PCI or PCA.