Rationale: Aggressive angiomyxoma (AAM) of the prostate should be considered as a differential diagnosis for prostatic tumor presenting with classical symptoms of benign prostatic hypertrophy.
Patient concerns: A 55-year-old man experienced persisting symptoms of prostatic enlargement associated with urinary frequency and urgency and nocturia. Computed tomography images showed low density in the enlarged prostate.
Diagnoses: The diagnosis of AAM of the prostate was confirmed based on histopathological findings.
Interventions: The patient underwent transurethral resection of the prostate.
Outcomes: The patient was enrolled into a watchful waiting protocol. His condition was fine without signs of recurrence on magnetic resonance imaging at the 8-month follow-up.
Lessons: AAM of the prostate should be considered a possible cause of urinary difficulty, including retention, although this may be extremely rare. A reliable diagnosis and complete tumor removal enabled optimal treatment and prevention of tumor recurrence.