Congenital Spindle Cell Rhabdomyosarcoma of the Urinary Bladder

Abstract

Spindle cell rhabdomyosarcoma is a recently described variant of embryonal rhabdomyosarcoma that carries a relatively favorable prognosis when compared with other types of rhabdomyosarcoma. We report the first case of a congenital spindle cell rhabdomyosarcoma in the urinary bladder of a newborn. The patient was diagnosed with obstructive uropathy and cystic kidneys in the antenatal period. The tumor was composed primarily of mature strap-shaped rhabdomyoblasts with cross-striations; it involved focally the full thickness of the bladder wall. No extension into adjacent organs or distant metastases were identified. The patient died of complications of urinary tract obstruction shortly after birth.