Fukushima Medical University Department of Urology
Introduction: The prostate volume and morphological features of the prostate are well known to be associated with lower urinary tract symptoms (LUTS) in the male patients. However, whether microscopic structural changes of prostate contribute to LUTS and lower urinary tract dysfunction (LUTD) has not been established. On the other hand, recent attention has focused on the apparent diffusion coefficient (ADC) which is a non-invasive functional MRI technique that can assess changes in diffusion of water molecules due to microscopic structural changes. We considered that the ADC can provide the quantitative information about the microscopic structural changes of the prostate. The aim of this study was to evaluate the effect of microscopic structural changes of prostate on LUTS and LUTD by evaluating the association between ADC values and LUTS and lower urinary tract function.
Methods: Patients who underwent MRI before random transrectal ultrasonography–guided prostate biopsy and had a diagnosis of benign by the biopsy at our hospital between May 2019 and January 2021 were included in this study. Before the biopsy, uroflowmetry parameter, bladder voiding efficiency (BVE); (voided volume/total bladder capacity) × 100, International Prostate Symptom Score (IPSS) and overactive bladder symptom score (OABSS) were evaluated. The voiding and storage IPSS sub-score (IPSS-V and IPSS-S, respectively) were recorded separately. We measured mean ADC value at the base of the prostate by MRI. The relationship between the mean ADC value and the parameters evaluated before the biopsy was analyzed. All values were expressed as mean ± standard deviation. A linear regression analysis was used for continuous variables. P-values of <0.05 were considered to be statistically significant.
Results: A total of 111 patients (68.9 ± 6.3 years) entered the study. The mean ADC value at the base of prostate was 1,468 ± 190 mm2/sec. The mean ADC value was significantly positively correlated with IPSS-S (C.C = 0.22, P=0.03) and OABSS (C.C = 0.25, P=0.02). The mean ADC value was significantly negatively associated with BVE (C.C = -0.22, P=0.04). The IPSS-V, maximum flow rate and bladder capacity were not significantly associated with the mean ADC value.
Conclusions: We demonstrated that high ADC value at the base of prostate caused storage symptoms and decreased the BVE. The microscopic structural changes of prostate reflected by high ADC value may affect lower urinary tract function through the different mechanism from the prostate volume and morphological features of prostate. The evaluating ADC value of prostate may provide individualized treatment options for patients