Prostate volume measured by magnetic resonance imaging is not a predictor of lower urinary tract symptoms

PURPOSE: Prostate volume is frequently utilized to counsel patients presenting to family medicine physicians with voiding complaints. We evaluated the relation between International Prostate Symptom Score (IPSS) and prostate volume measured by phased-array surface coil magnetic resonance imaging (MRI). METHODS: We performed an institutional review board (IRB)–approved retrospective study of all patients who received a prostate MRI between 2015 and 2017. Correlation between the overall IPSS, IPSS components, prostate volume stratified by prostate specific antigen (PSA) (<1.4 vs. ≥1.4 g/dL), and race (black vs. white) was examined. RESULTS: In all, 592 patients had prostate MRIs performed between 2015 and 2017. Two hundred and twenty-nine of these patients had IPSS and prostate volume information available in their medical records. The mean age of the cohort was 64.67 (SD = ±7.82) and mean PSA was 7.75 (SD = ±8.3). The mean IPSS was 9.77 (SD ± 7.2), and mean prostate volume was 55.88 cubic cm (SD = ±38.9). The correlation coefficient between prostate volume and IPSS was 0.12789 (P = 0.05). The correlation between prostate volume and IPSS was also not significant in 128 men with prostate volume above 40 cubic cm. Stratifying analysis by race and PSA showed no significant correlation between volume and IPSS. Analysis of the correlation between the different dimension of prostate volume and IPSS revealed significant but weak associations. CONCLUSIONS: Even with more precise estimation with MRI, prostate volume does not predict obstruction complaints. This finding is of importance when treating males presenting with voiding dysfunction to primary care.