Role of radiation therapy in pediatric cancer

Although the incidence of childhood cancer has stabilized over the past few years, approximately 12,000 new cases are diagnosed each year in the United States among patients who are 19 years or younger [1,2]. Common childhood cancers include leukemia, lymphoma, central nervous system (CNS) tumors, neuroblastoma, Wilms' tumor, and sarcomas [3]. There have been statistically significant differences in the 5-year survival rates for childhood cancer between the periods of 1974 to 1976 and 1992 to 1999, which are 56% and 78%, respectively [4]. Die overall increase in the survival rate for childhood cancer has been attributed to advances in chemotherapeutic agents, refinements in bone marrow transplantation, Improvements in surgical and radiotherapy techniques, and the centralization of care through cooperative oncology groups. In the United States, it is estimated that approxmiately 90% of childhood cancers are treated by a Children's Oncology Group (COG) affiliated institution [5]. The treatment of childhood cancer is often regarded as one of the great successes of contemporary medicine. Radiotherapy has had an important role in the treatment and cure of childhood tumors. Unfortunately, it has also been associated with adverse late effects on growth and development, endocrine function, gastrointestinal dysfunction, musculoskeletal and integumentary hypoplasia, cardiac dysfunction, endocrine effects, and second malignancies [6]. The most challenging issue in radiotherapy for childhood tumors is minimizing the late effects of therapy among survivors. The current role of radiotherapy in management of the most common childhood malignancies as well as new approaches and technologies addressing the issue of late effects are discussed herein.