Contrast-Enhanced Ultrasound (CEUS) Evaluation of Canine Prostatic Hyperplasia before and after Osaterone Acetate Therapy: Preliminary Results

Abstract

Simple Summary The contrast-enhanced ultrasound (CEUS) allows the evaluation of the vascularization of an organ, using contrast agents composed of gas microbubbles, such as sulfur hexafluoride. Prostate perfusion is increased in dogs with benign prostatic hyperplasia (BPH), due to the stimulation of dihydrotestosterone (DHT). In the present study, CEUS is applied for monitoring dogs with BPH, receiving osaterone acetate (OSA). Fifteen intact adult dogs are referred for BPH. A CPSE assay and B-mode ultrasound confirm the diagnosis. CEUS is performed before OSA treatment (D0) and highlights the rapid diffusion times of the contrast agent (length of the wash-in and wash-out phases). Prostatic cysts and parenchymal alteration are also detected. After treatment (D1), the CPSE and prostate volume are significantly reduced, while CEUS detects a significant increase in wash-in and wash-out times and a reduction in parenchymal abnormalities. These findings confirm the decrease in prostatic perfusion after OSA treatment and, although preliminary, are promising for the broader use of CEUS for the diagnosis and monitoring of dogs with BPH. Abstract The prostate is the only sexual gland of the male dog, and dihydrotestosterone (DHT) regulates its growth. In intact dogs, constant DHT stimulation results in benign prostatic hyperplasia (BPH) that can be treated with osaterone acetate (OSA). This study describes the effects of OSA treatment, detected by contrast-enhanced ultrasonography (CEUS), highlighting prostatic vascularization with a contrast agent composed of gas microbubbles. Fifteen dogs (2–8 years) of different sizes and breeds (4–30 kg) diagnosed with BPH are involved in the study. Before treatment (D0), CPSE is measured (294.05 ± 115.97 ng/mL), and a B-mode ultrasound is performed (Vratio = 2.80 ± 1.85), confirming BPH. CEUS highlights the length of the wash-in (11.93 ± 2.08 s) and wash-out (42.20 ± 6.99 s) phases of the contrast agent in the prostate and the presence of cysts and parenchymal alteration. Dogs are treated with OSA (0.5 mg/kg for 7 days) and reassessed after 21 days (D1): CPSE and prostate volume are significantly (p < 0.001) reduced. The length of the wash-in (14.73 ± 2.54 s) and wash-out (51.13 ± 6.03 s) phases are significantly (p < 0.001) increased. The results confirm the effectiveness of the treatment, particularly the reduction in prostatic perfusion, confirmed by the increase in diffusion times of the contrast. Although preliminary, these findings are promising for the use of CEUS in monitoring dogs with BPH.