Care and treatment of long-term survivors of childhood cancer.

With the advances in the therapy of childhood cancers over the past 30 years, many children who are now cured of their cancer are moving into adulthood. These patients have, in many cases, been exposed to multiple therapeutic modalities (chemotherapy, radiation, and/or surgery), and in recent years have experienced more and more intensive therapies. Potential late sequelae can involve almost any organ system, but can be predicted, in part, by the chemotherapy or radiation that individuals may have received. These complications may be categorized by their timing relative to the discontinuation of therapy: early (under 5 years), intermediate (5-20 years), or very late (over 20 years). Four potential late sequelae are reviewed (thyroid, cataracts, renal, and osteoporosis), and recommendations are made for screening of at risk individuals for these long-term complications. The need for long-term follow-up of this unique group of individuals is critical as we attempt to completely define the risks and benefits of our therapeutic efforts.