Vascular resistance in the prostate evaluated by colour Doppler ultrasonography: is benign prostatic hyperplasia a vascular disease?

There is a wide variety of topics in this section of the Journal this month. The papers come from Austria, Israel, Scotland, Denmark, England and Australia. I am, as ever, pleased that the Journal continues to receive papers from so many countries, and that the high standard of these papers help us to maintain a quality product of great general interest to the reader. OBJECTIVE To evaluate prostatic vascular resistance by measuring the resistive index (RI), and flow velocity using colour Doppler ultrasonography (CDUS), in normal prostates and in patients with benign prostatic hyperplasia (BPH) or prostate cancer, as BPH is considered to be a result of urogenital ageing and studies suggest that hyperplasia in the stromal and glandular compartments might be induced by stromal growth secondary to hypoxia, which in turn results from abnormal blood flow patterns. PATIENTS, SUBJECTS AND METHODS Ninety‐two men (22 with normal prostates, 45 with BPH and 25 with prostate cancer; mean age 56 years) were prospectively evaluated by CDUS. The RI values for the peripheral, central and transition zones were assessed by one investigator. The diagnosis of BPH and prostate cancer was established from histological findings. RESULTS The mean ( sd ) RI in the transition zone was significantly higher only in patients with BPH, at 0.77 (0.05), vs 0.65 (0.05) in the other two groups. In the peripheral and central zones there was no significant difference in the RI among the three groups. Arterial CDUS flow velocity was increased in the transition zone of patients with BPH, but not in the peripheral and central zones. CONCLUSIONS The present results support the hypothesis that an age‐related impairment of blood supply to the lower urinary tract might have a role in the development of BPH. Although prostate cancer cannot be excluded by measuring RI, high RI values (>0.75) in the transition zone are indicative of BPH.