年輕男性之侵襲性臍尿管黏液腺癌合併骨盆腔復發：病例報告與文獻回顧

許智凱、張廷瑞、陳世亮

台南市立醫院 泌尿科

Aggressive Urachal Mucinous Adenocarcinoma with Pelvic Recurrence in a Young Male: A Case Report and Literature Review

Chih-Kai Hsu, Ting-Jui Chang, Shih-Liang Chen

Divisions of Urology, Tainan Municipal Hospital, Tainan, Taiwan

Introduction: Urachal adenocarcinoma is an extremely rare and aggressive malignancy, accounting for less than 1% of all bladder cancers. Arising from urachal remnants, it predominantly affects middle-aged adults and often presents at an advanced stage. Among its subtypes, mucinous adenocarcinoma is characterized by abundant mucin production and can be diagnostically challenging. We present a case of a 37-year-old male diagnosed with locally advanced urachal mucinous adenocarcinoma who developed pelvic recurrence and was successfully managed with multimodal therapy.

Case Report: A 37-year-old male presented with gross hematuria with clots. He had no history of hypertension or diabetes but was a smoker. Cystoscopy revealed a solid tumor at the bladder dome, and a transurethral resection of bladder tumor (TURBT) was performed. Initial pathology suggested mucinous adenocarcinoma suspected of urachal origin. The patient underwent an open partial cystectomy with en bloc resection of the urachus and pelvic lymph node dissection. The final pathology confirmed urachal adenocarcinoma, mucinous type, stage pT3N0M0, with invasion into the bladder and peri-vesical soft tissue, and perineural invasion was present. The patient was lost to follow-up for three months post-operatively. Upon return, a follow-up CT scan revealed a local recurrence at the right pelvic sidewall with tumor progression. He was referred to a medical center for open tumor resection, followed by concurrent chemoradiotherapy (CCRT). As of the latest follow-up, the patient shows no evidence of recurrence.

Discussion: Urachal adenocarcinoma typically carries a poor prognosis due to its silent clinical course and late presentation. The mainstay of treatment is surgical wide excision, specifically partial or radical cystectomy with en bloc resection of the umbilicus and urachal ligament. This case highlights the aggressive nature of the mucinous subtype and the critical importance of strict follow-up. Despite the recurrence, aggressive surgical salvage combined with CCRT has provided disease control. Clinicians should maintain a high index of suspicion for urachal remnants in young patients presenting with dome tumors to ensure timely and aggressive management.