Rhabdomyosarcoma (RMS) of the Renal Pelvis in a Child: A Case Report

Rhabdomyosarcomas (RMS) of the kidney is extremely rare. We are reporting one case of embrional rhabdomyosarcoma localized in a child renal pelvis, focusing on the rarity of the site and role of imaging. An 8-years-old boy was admitted to the hospital with abdominal pain and hematuria. Ultrasonography revealed a right ureteropyelectasy including an echogenic image that extended from the renal pelvis towards inferior basin with no hypervascularization, simulating a clot. The urography-magnetic resonance imaging (Uro-MRI) showed two different components of the lesion: the first one simulating a clot; the second one detected in the papillary region and extended to the inferior calices having tumor-like features. A percutaneous ultrasound-guided renal biopsy revealed a botryoid embryonal rhabdomyosarcoma. The RMS is a complex childhood malignancy. This complexity is reflected in the radiological assessment that remains highly challenging and in the absense of treatment guidelines for unusual sites.