Embryonal rhabdomyosarcoma arising in the ureter.

Embryonal rhabdomyosarcoma, botryoid variant, is a malignant tumor that usually arises in the urinary bladder and other mucosal sites. This is a case of a 4-year-old girl presenting with a mass initially thought to arise within the urinary bladder. Macroscopic and microscopic examination proved that this botryoid rhabdomyosarcoma had its origin within the left ureter.