[Paratesticular rhabdomyosarcoma].

Report of one paratesticular RMS in a 28 year-old male. The paper includes a review of the various clinical, etiopathogenic and therapeutic features involved. RMS is a neoplasia difficult to diagnose through M.O. and, quite often, it is necessary to use immunohistochemical techniques in order to discover some of the muscular fibre markers, such as Desmin, Myosin and Myoglobin. Several theories have been put forward to explain its origin, and the most widely accepted defends an origin in a poorly differentiated mesenchymal tissue. The advantages of retroperitoneal lymphadenectomy following orchiectomy are discussed as treatment.