The post-cystectomy pseudotumour sign: MRI appearances of a modified chronic pelvic haematoma due to retained haemostatic gauze.

The magnetic resonance imaging (MRI) findings of five men who had incidental similar pelvic masses identified after radical cystectomy are presented. In all patients the haemostatic agent Kaltostat had been used. In one patient, surgical resection of the mass was performed and histological evaluation showed a foreign body inflammatory reaction within a chronic haematoma. The differentiation between this lesion and other post-operative collections or tumours is discussed.