Radiation therapy for pediatric central nervous system tumors.

Radiation therapy is an important component of treatment of many pediatric central nervous system tumors. The radiation treatment target is determined by tumor histology, extent of disease, anticipated pattern of spread, and expected pattern of failure. Children cured of their tumors live to experience the long-term sequelae of radiation treatment, including developmental, neurocognitive, neuroendocrine, and hearing late effects. The development of more conformal radiation techniques has decreased inadvertent radiation dose to normal tissues and should decrease long-term treatment sequelae that are the result of normal tissue radiation. Intensity-modulated radiation therapy improves treatment conformity and decreases high dose to nearby normal tissues; however, it delivers a larger volume of low- and intermediate-dose radiation. Proton radiation eliminates exit dose to normal tissues, thereby eliminating approximately 50% of unnecessary radiation to normal tissues. The long-term clinical benefits of proton radiation in the pediatric population are just beginning to be reported in the literature.