Urethra-sparing surgery for a prostate cancer lesion in the anterior urethral zone with magnetic resonance-guided focused ultrasound: a case report

Prostate cancer (PCa) is the most common malignancy among men worldwide. High-intensity focused ultrasound (HIFU) is a focal therapeutic strategy for low- to intermediate-risk PCa with a low risk of complications. However, lesions located in the anterior urethral zone are challenging to treat with this approach because it is difficult to avoid urethral injury during HIFU therapy, which might further cause urethral stricture and symptoms related to bladder outlet obstruction (BOO). Here, we present the case of a 79-year-old male with elevated prostate-specific antigen (PSA) levels for over 1 year. Multiparametric magnetic resonance imaging revealed a 1.8 cm × 1.0 cm mass covering an area of the anterior urethral zone. Histopathological examination revealed an International Society of Urological Pathology grade group 3 acinar adenocarcinoma. Given the patient’s request for functional preservation, a magnetic resonance-guided focused ultrasound surgery was performed. During the operation, a urethra-sparing approach was utilized by administering proper energy and adjusting the sequence of the sonications. The patient developed urinary retention after catheter removal less than 48 h after the treatment, which resolved after removal of the second catheter a week later. On a follow-up visit 3 months after the treatment, evaluation by the level of PSA and multiparametric magnetic resonance imaging showed no recurrence of PCa. No significant changes in the International Prostate Symptom Score and Quality of Life score were found compared to baseline scores. With proper adjustment, magnetic resonance-guided focused ultrasound surgery could be safely used for urethra-sparing surgeries for PCa lesions in the anterior urethral zone, without influencing post-treatment urination. The indwelling time of the catheter should be extended appropriately for full recovery from treatment-related prostatic edema around the prostatic urethra to avoid urinary retention.