Retroperitoneal teratoma.

The authors present a case of benign retroperitoneal teratoma in a 3-year-old boy, involving left-sided hydronephrosis. Urography demonstrated that the tumour (as seen in the review photograph) displaced the left kidney and induced considerable hydronephrosis. Operation was performed consisting in removal of the tumour along with the left kidneys, whose artery was closely fused with the tumour. Within the postoperative course no complications occurred.