Plaque radiotherapy for residual or recurrent retinoblastoma in 91 cases.

Plaque radiotherapy has been used successfully as primary treatment for selected solitary retinoblastomas. However, there is relatively little information on its role as a secondary treatment after other methods have failed to control the tumor. We have used solitary plaque radiotherapy to treat 91 children with residual or recurrent retinoblastoma after failure of one or more treatment modalities, which included external beam radiotherapy in 63 children, plaque radiotherapy in 9, cryotherapy in 26, and photocoagulation in 18, for a total of 116 treatments in the 91 children. Despite the fact that enucleation was considered to be the only remaining option in many of these children, tumor regression was achieved in 81 cases (89%) and recurrence developed in only 10 cases (11%) during a mean follow up lf 52 months. Treatment of the recurrence following plaque radiotherapy in these 10 cases included repeat plaque radiotherapy in 6 cases, enucleation in 3 cases, and external beam radiotherapy in 1 case. In view of the fact that enucleation was being considered as the only remaining option in many of these children, control of the tumor with plaque radiotherapy in 89% of the cases is very encouraging. Plaque radiotherapy should be considered as an important option for recurrent retinoblastoma after failure of other methods to achieve tumor control.