Role of radiation therapy in parameningeal rhabdomyosarcoma.

Radiation therapy plays a crucial role in the management of children with parameningeal rhabdomyosarcomas. Because of the close proximity to the skull base, most lesions are not amenable to complete surgical resection without mutilation, and treatment has primarily been chemoradiation. Adequate radiotherapy dose, coverage of the tumor, and knowledge of potential areas of invasion are of paramount importance as demonstrated by early data from the Intergroup Rhabdomyosarcoma Study Group. The timing, dose, and treatment volume for parameningeal rhabdomyosarcomas have evolved in the last 25 years in a continuous effort to find ways of maximizing local control while reducing possible late sequelae. Hyperfractionated radiation therapy is currently being tested against conventional dose radiation therapy for group III tumors. At present, approximately 70% of children treated for parameningeal rhabdomyosarcoma on the Intergroup Rhabdomyosarcoma Study are alive at 5 years compared with a 25% survival before the formation of multi-institutional cooperative group studies.