Intraocular Retinoblastoma Treatment
The International Classification system for staging intraocular retinoblastoma is a better predictor of treatment success for the use of systemic chemotherapy in combination with local control. (Refer to the Treatment Options Under Clinical Evaluation section of this summary for a more complete description of the International Classification system.) The combinations of carboplatin and etoposide (CE) [22,65] or CEV [66,67] in conjunction with local control have resulted in ocular salvage rates above 90% for early intraocular disease (Groups A and B eyes), 70% to 90% for Group C eyes, and 40% to 50% for Group D eyes.[22,65,67]; [Level of evidence: 3iiDiv] However, for patients with advanced intraocular disease (typically Group D eyes), EBRT is frequently required for ocular salvage.; [Level of evidence: 3iiDiii]
For patients with large intraocular tumor burden or with subretinal or vitreous seeds (Groups C and D eyes), the use of periocular chemotherapy, usually in combination with systemic therapy, has been explored.[26,68] However, the outcome of this approach on ocular salvage is not well defined.
The treatment recommendation for Group E eyes is up-front enucleation. The use of prolonged systemic chemotherapy for Group E eyes to avoid or delay enucleation has been associated with lower disease-specific survival (P < .001).[Level of evidence: 3iiiB]
Delivery of chemotherapy via ophthalmic artery cannulation has also been shown to be feasible and effective in patients with bilateral disease, in both the up-front and salvage settings.[31,35][Level of evidence: 3iiDii] However, this treatment should only be performed in an experienced center with a state-of-the-art treatment infrastructure and a dedicated multidisciplinary team.
The unresolved issues are long-term tumor control and the consequences of chemotherapy. Most of these patients are exposed to etoposide, which has been associated with secondary leukemia in patients without predisposition to cancer, but at modest rates when compared to the risk of EBRT in hereditary retinoblastoma. In a retrospective database and literature review, cases of secondary acute myeloid leukemia were identified among children who received epipodophyllotoxins. The actuarial risk for leukemia is not known and it is unclear whether the risk for children with retinoblastoma receiving topoisomerase II inhibitors exceeds the risk that exists for other children.