Toddler with recently noted urinary retention

IVP and CT of rhabdomyosarcoma of the bladder
AP image from the excretory phase of a vintage intravenous pyelogram (above) shows bilaterally normal appearing renal collecting systems and ureters. There is a multilobulated circumferential filling defect in the base of the badder. Axial CT with contrast of the abdomen shows the mass to almost complete fill the base of the bladder.

The diagnosis was rhabdomyosarcoma of the bladder.