The role of chemotherapy in the treatment of retinoblastoma.

A review of the current status of chemotherapy in the treatment of retinoblastoma is presented. No consistently effective chemotherapeutic regimen for intraocular tumor has yet been discovered. An adjunctive role in the treatment of extraocular orbital disease has been suggested, but is unproven. Central nervous system involvement often responds to intrathecal chemotherapy. In cases diagnosed early, cure may be possible by the use of aggressive regimens including radiation therapy. Complete remissions are generally achieved in patients with systemic metastases. Cyclophosphamide is the most effective of the drugs used so far. However, relapses invariably follow, because effective maintenance chemotherapy has not yet been developed. Prevention of overt metastases by the use of adjuvant chemotherapy has recently been studied, but results remain inconclusive. Identification of reproducible prognostic criteria will enhance the design of future clinical studies. Laboratory research shows promise of more effective chemotherapeutic agents and combinations.