變異型齊納氏症候群合併局部攝護腺癌成功接受機器手臂輔助攝護腺切除手術治療

– 案例報告

陳米妮¹、陳人傑^1,2、黃逸修^1,2

¹台北榮民總醫院 泌尿部；²陽明大學醫學院泌尿學科暨書田泌尿學研究中心

Variant Zinner Syndrome Patient Developed Localized Prostate Cancer and Was Successfully Treated with Robotic-Assisted Radical Prostatectomy: A Case Report

Minnie Chen¹, Jen-Chieh Chen^1,2, Eric Yi-Hsiu Huang^1,2

¹Department of Urology, Taipei Veterans General Hospital, Taipei, Taiwan

²Department of Urology, College of Medicine and Shu-Tien Urological Science Research Center
National Yang Ming Chiao Tung University, Taipei, Taiwan

Introduction

Zinner syndrome is a rare congenital malformation of the mesonephric (Wolffian) duct, typically characterized by the triad of ipsilateral renal agenesis, seminal vesicle cyst, and ejaculatory duct obstruction. In most cases, the ureter of the affected side drains into the bladder. However, a variant form of Zinner syndrome can occur, in which the ureter drains directly into the seminal vesicle or prostate. Zinner syndrome may be associated with various urological disorders, yet according to the literature, only two patients with Zinner syndrome have been reported to develop prostate cancer. Notably, both of these cases were the variant form, with the prostate cancer arising on the side where the ureter drained. Here, we report the third case, representing the first such case from Asia.

Case Report

A 61-year-old man presented with a 2–3 year history of progressive lower urinary tract symptoms, including weak stream, intermittency, urgency, and nocturia. His serum prostate-specific antigen (PSA) level increased from 5.36 to 12.9 ng/mL over 12 months. Multiparametric magnetic resonance imaging (MRI) revealed absence of the right kidney, with a blind-ending ureter draining into the right seminal vesicle, resulting in right hydroureter and a dilated right seminal vesicle, consistent with a variant form of Zinner syndrome. Additionally, a 2-cm lesion was identified in the right central zone of the prostate, showing diffusion restriction and early enhancement on dynamic contrast-enhanced sequence, consistent with a PI-RADS 5 lesion. Notably, the lesion was located around the right ejaculatory duct and in the region where the right ejaculatory duct drains. A detailed family history revealed that the patient’s elder brother had also been incidentally diagnosed with Zinner syndrome during a routine health examination. Both individuals were asymptomatic and denied dysuria, perineal discomfort, or painful ejaculation. The patient had fathered one child, indicating preserved fertility.

Targeted prostate biopsy confirmed prostate adenocarcinoma with a Gleason of 3+4=7, while all systemic biopsy cores were negative. The patient underwent robotic-assisted radical prostatectomy with bilateral standard pelvic lymph node dissection. Intraoperatively, a blind-ending right ureter draining into the right seminal vesicle was identified. Bilateral nerve-sparing was successfully achieved. Final pathology revealed organ-confined adenocarcinoma (pT2), Gleason 3+4=7, with negative surgical margins and no lymph node metastasis. The urinary catheter was removed on postoperative day 7, with immediate restoration of continence. At 1-month follow-up, erectile function was preserved, and the serum PSA level was undetectable.

Discussion

Zinner syndrome is asymptomatic in approximately 60–70% of patients, and these cases are often managed with observation and regular follow-up. However, our case highlights that variant Zinner syndrome may warrant closer surveillance, as aberrant ureteral drainage could be associated with the development of localized prostate cancer. Careful preoperative imaging, including multiparametric MRI, is essential to delineate variant anatomy and tumor location. The RARP can be safely and effectively performed in such anatomically complex cases. Finally, reporting this case is crucial to improve understanding of the potential relationship between variant Zinner syndrome and prostate carcinogenesis.

Conclusion

Even in patients with asymptomatic variant Zinner syndrome, careful monitoring of the prostate may be warranted, as aberrant ureteral drainage could predispose to localized prostate cancer.