15.8.3 Bilateral Retinoblastoma

•Initial enucleation of one eye in patients with asymmetric tumors, for example, one eye, groups 1 or 2; the other eye, groups 3–5. Sometimes both eyes and vision can be preserved with initial use of chemotherapy

•Otherwise first treatment choice is chemotherapy in combination with the other mentioned options (see above); in patients with nonresponsive disease, unior bilateral enucleation may be necessary

15.9Prognosis

•Survival: 80–90% of all patients with retinoblastoma after risk-adapted therapy and dependent from adequate experience of pediatric ophthalmo-oncology

•Poor prognosis in developing countries

15.9.1 Risk of Secondary Tumors

•In bilateral retinoblastoma, risk is 11–13%

•Occurrence of secondary malignancy is highest several years after first tumor, but risk persists throughout life, the frequency is in the range of 3–6%

•Most frequent tumors:

–Osteogenic sarcoma − 75% within the irradiated area, with remainder in nonirradiated sites; incidence 500 times higher than the primary osteogenic sarcoma in patients without inherited retinoblastoma

–Pinealoblastoma, which is highly invasive and usually fatal. This phenomenon, also called trilateral retinoblastoma, may be decreased in frequency after initiation of systemic chemotherapy

–Rhabdomyosarcoma, sinus maxillary sarcoma, and other STS may develop