Advanced bilateral retinoblastoma treated conservatively with lens sparing external beam radiation therapy: report of three cases.

From 1995 through 1998, 3 children with bilateral advanced retinoblastoma were treated primarily with external beam radiation therapy; 6 eyes were irradiated with a lens sparing technique, doses varied from 5500 to 5700 cGy, and follow-up period ranged from 14 to 36 months. Recurrent tumors were found in 3 eyes, and a new growing tumor in one eye. Three eyes underwent enucleation eventually; one eye refused enucleation and finally developed optic nerve extension. The overall ocular cure rate was 2/6 (33.3%). One eye sustained visual acuity of 20/30, the other eye retained some peripheral vision; both eyes were blind in one patient. There were no deaths, metastasis, or secondary malignant tumors in our study. Advanced bilateral retinoblastoma with simultaneous radiation therapy instead of bilateral enucleation does not increase the risk of death, and more children will enjoy the benefits of retaining some vision in the affected eye through the use of this conservative therapeutic regimen.