Late effects of treatment of cancer in children.

Over the past two decades, owing to advances in surgical techniques, chemotherapy, and radiation therapy, there has been dramatic improvement in the survival of children with malignancies. Children cured of cancer will soon form a significant fraction of our adult population. As we follow such survivors, we have become more aware of long-term side effects of treatment. Therapy should not be withheld. Instead, careful follow-up of oncology patients is needed to document the adverse late effects, to identify the etiologic agents, and to alter treatment to give the least toxic therapy without sacrificing the quality or duration of survival.