9. Treatment of Extraocular Retinoblastoma

Retinoblastoma is the most common primary eye tumor in children worldwide. The presentation of disease in higher-income countries is almost universally intraocular in nature with highly favorable survival rates. This is due in part to the availability of multi-modality treatment options including enucleation, chemotherapy, local therapies, and external beam radiation therapy. In contrast, retinoblastoma most commonly presents as extraocular disease in lower-income nations often with poor prognostic outcomes. This chapter reviews the diagnosis and management options for the various stages of extraocular retinoblastoma.

In order to effectively standardize care for the treatment of retinoblastoma, an international staging system was proposed in 2006 as a consensus document. The authors of this chapter recommend that the classification of extraocular disease proposed in this system be used. In this system, stage II corresponds to microscopic residual tumor after eye enucleation. Stage III describes regional extension, including overt orbital disease or preauricular or cervical lymph node extension. Stage IV comprises metastatic disease with and without central nervous system extension (stages IVb and IVa disease, respectively).

This chapter describes the treatment options described in the scientific literature for treatment of the various stages of extraocular disease. Publications from multiple international groups have validated that patients with stage II or III disease can be cured with a combination of conventional, systemic chemotherapy, and external beam radiation therapy. By contrast, patients with stage IVa and IVb disease have poor outcomes when treated with similar protocols. However, when treatment is intensified to include high-dose chemotherapy followed by autologous stem cell rescue, there is potential for cure in patients with metastatic disease.