Recurrent giant multilocular prostatic cystadenoma: A case report after a decade in Vietnam

Giant multilocular prostatic cystadenoma is a rare benign tumor with high recurrence rates and aggressive local growth. We report a 41-year-old man with nearly a decade of recurrent disease presenting with worsening urinary symptoms, pelvic pain, and defecatory difficulties. Despite multiple procedures including transurethral resection and robotic cyst excision with benign histopathology, recurrence persisted. In 2025, MRI revealed a massive multiloculated cystic mass (106×109×174 mm) compressing the rectum and prostate with elevated PSA (38 ng/mL). Given recurrent disease and severe pelvic compression, he underwent radical prostatectomy with en bloc cyst excision. Three-month follow-up showed no recurrence and complete symptom resolution. • Giant multilocular prostatic cystadenoma is a rare benign tumor in the prostate that can be misdiagnosed as malignant. • It may have long recurrence periods, so patients need annual follow-ups. • In some cases, radical prostatectomy may be necessary to prevent recurrence.