Haemorrhagic papillary cystadenoma of the seminal vesicle mimicking giant seminal vesicle cyst: MRI appearances.

Papillary cystadenoma of the seminal vesicle is very rare. We describe such a case presenting in a 58 year old man with bladder outlet obstruction. Investigations included magnetic resonance imaging (MRI), the usefulness of which in pre-operative diagnosis is highlighted in this case. Seminal vesicle cysts can usually be identified by conventional radiological imaging techniques such as ultrasound and computed tomography; however, identification would be difficult if the cyst is very large, causing distortion of the adjacent anatomy. In such cases, MRI, through coronal and sagittal scanning, can be helpful in localising the lesion, as in this patient. The precise pathological nature of the cyst can only be confirmed by biopsy.