Standard treatment options
Because unilateral disease is usually massive and there is often no expectation that useful vision can be preserved, surgery (enucleation) is usually undertaken and radiation therapy is not given to the tumor bed. However, patients with unilateral disease have been treated with chemotherapy in an attempt to preserve vision in the affected eye.[2,29,30] One study revealed that children with retinoblastoma who present with obvious external findings of leukocoria, strabismus, or red eye detectable by their family or pediatrician most often require enucleation. Children who manifest no obvious external findings can often avoid enucleation.
When there is potential for preservation of sight because the tumors are smaller, treatment with other modalities (radiation therapy, laser therapy [thermotherapy], cryotherapy, chemoreduction, and brachytherapy) instead of surgery should be considered. In selected children with unilateral disease, chemoreduction reduced the need for enucleation or EBRT to 68% within 5 years of treatment. R-E Group correlated with successful chemoreduction: 11% of children classified as having R-E Group II or III disease, 60% of children having R-E Group IV disease, and 100% of children having R-E Group V disease required enucleation or EBRT within 5 years of treatment. A pilot study evaluated the delivery of chemotherapy via ophthalmic artery cannulation as initial treatment of advanced unilateral and bilateral intraocular retinoblastoma.
Because a proportion of children who present with unilateral retinoblastoma will eventually develop disease in the opposite eye, it is very important that children with unilateral retinoblastoma receive periodic examinations of the unaffected eye. Asynchronous bilateral disease occurs most frequently in patients with affected parents.
Careful examination of the enucleated specimen by an experienced pathologist is necessary to determine whether high-risk features for metastatic disease are present. These include anterior chamber seeding, choroidal involvement, tumor beyond the lamina cribrosa, or scleral and extrascleral extension.[33,34,35] Systemic adjuvant therapy with vincristine, doxorubicin, and cyclophosphamide, or vincristine, carboplatin, and etoposide, has been used in patients with certain high-risk features assessed by pathologic review after enucleation to prevent the development of metastatic disease.[36,37,38,39]; [Level of evidence: 2A]
Treatment options under clinical evaluation
The following is an example of a national and/or institutional clinical trial that is currently being conducted. Information about ongoing clinical trials is available from the NCI Web site.
- The Children's Oncology Group (COG) is conducting a study of unilateral retinoblastoma with high-risk features using a standard regimen of six cycles of carboplatin, etoposide, and vincristine.
The management of bilateral disease depends on the extent of the disease in each eye. Systemic therapy should be chosen based on the eye with more extensive disease.
Standard treatment options
Usually the disease is more advanced in one eye, with less involvement in the other eye. In the past, the standard of care has been to enucleate the more involved eye. When disease is massive and there is no expectation that useful vision can be preserved, surgery is usually undertaken and radiation therapy is not given. However, if there is potential for vision in both eyes, primary chemoreduction with close follow-up for response and focal treatment (e.g., cryotherapy or laser therapy) may be indicated. EBRT is now reserved for patients whose eyes do not respond adequately to primary systemic chemotherapy and focal consolidation.