Radiation therapy in retinoblastoma. An analysis of 230 cases.

Retinoblastoma is a rare, congenital, malignant tumor which predominantly affects infants and young children. Approximately 65 per cent of the cases are unilateral, are generally far advanced in the globe when first seen, and are treated by enucleation (5). In 35 per cent, tumors are found in both eyes, either simultaneously or within a short time of each other; in these, it is usual to enucleate the more severely affected eye because it is unlikely that useful vision can be maintained and to irradiate the less involved eye in an attempt to preserve sight. A smaller group of cases, those with early unilateral or bilateral disease, are also treated with radiation (6). In addition, irradiation is given for postoperative residual or recurrent disease and as a palliative measure for distant metastases. Although excellent studies are available, assessing the survival results and genetics of retinoblastoma, none has analyzed the local control rate due to radiation therapy, the effect of currently employed radia...