Ultrasound diagnosis of paratesticular rhabdomyosarcoma.

Rhabdomyosarcoma is the most common tumour of the lower genitourinary tract in children in the first two decades. Paratesticular rhabdomyosarcoma is associated with a significantly better outcome than lesions elsewhere in the genitourinary tract. Although ultrasound is considered the imaging modality of choice for evaluating intrascrotal pathology, the ultrasound appearance of paratesticular rhabdomyosarcoma has rarely been reported and may be confused with other disease entities such as epididymitis, adenomatoid tumour and leiomyoma. We present the ultrasound features of a paratesticular rhabdomyosarcoma, discussing the clinical features and differential diagnosis.