Retinoblastoma remains a rare disease, but still one which has an uncertain life and functional prognosis. The diagnosis is often made late because the principal signs such as leukokoria and strabismus have not been recognized, thus a conservative treatment is no longer possible. However, when treated at an early stage, a child suffering from retinoblastoma has every chance of a complete cure and even normal vision may be preserved. Irradiation therapy plays an essential role, using local radiation by radioactive applicators or by external Betatron electron beams. Based on 52 cases, the methods of treatment and the results obtained at the Ophthalmology Department of Lausanne are reported, including one case of spontaneous cure of a bilateral retinoblastoma.