A rare benign genitourinary tumor in a Japanese male: urinary retention owing to aggressive angiomyxoma of the prostate.

Close examination of a 67-year-old Japanese man, who complained of persistent nocturia, revealed that a semitransparent polypoid tumor had developed from the bladder neck to the prostatic urethra obstructing the internal urethral meatus, which resulted in excessive urinary retention and post-renal dysfunction. The tumor was resected by a transurethral procedure and a pathological examination of specimens revealed aggressive angiomyxoma (AAM) of the prostate. AAM usually develops in the intrapelvic and perineal organs of females. So far as we know, this is the second case of primary prostatic AAM reported in the English literature, and is the first case where the patient encountered urethral obstruction.