Complete resolution of a large seminal vesicle cyst--evidence for an obstructive aetiology

Seminal vesicle cysts may arise from inflammation or obstruction of the seminal vesicle or from embryological remnants such as the müllerian duct. Surgical removal has been proposed as the treatment of choice. A 19-year-old boy presented with abdominal pain and constipation. Investigations revealed a 14-cm multiloculated cyst arising from the right seminal vesicle and a small stone lodged at the orifice of the ipsilateral ejaculatory duct. Following endoscopic removal of the stone the mass decreased in size considerably and 2 months later transrectal ultrasound and magnetic resonance imaging showed normal seminal vesicles and no evidence of the cyst. This case strongly supports an obstructive aetiology for this cyst and we would suggest that, in similar cases, full assessment of the ejaculatory apparatus should be carried out to exclude an obstructive cause before embarking on major surgery.