Protocol for the Study and Treatment of Participants With Intraocular Retinoblastoma

Participants will be stratified into four main treatment groups, depending on whether retinoblastoma is present in one or both eyes and disease grouping [early or advanced, Reese-Ellsworth (R-E) group I-V, and International Classification A-E]. Additionally, participants will be invited to participate in exploratory research objectives that address cognitive and functional development of children with retinoblastoma, the pharmacokinetics of topotecan in young children, and evaluation of ototoxicity, including genetic analysis.

TREATMENT PLAN

STRATUM A:

• Children ≥ or equal to 6 months old at time of enrollment - 8 courses of vincristine and carboplatin, given at 3-4 week intervals.
• Infants < 6 months old at time of enrollment - Therapy will consist of six courses of chemotherapy; three courses of vincristine and carboplatin, given at 3-4 week intervals, alternating with 3 cycles of vincristine and topotecan, given at 3-4 week intervals.

Focal treatments will be administered at the discretion of the treating team. Focal therapies will include cryotherapy, laser photocoagulation, thermo-therapy and plaque radiotherapy.

STRATUM B:

• Participants without extensive sub-retinal (SR) seeding, treatment will consist of two up-front courses of vincristine and topotecan, given at 3-4 week intervals.
• Participants without SR seeding: ≥ or equal to partial response after 2 cycles, will receive three additional courses of vincristine-topotecan (VT) and six courses of vincristine-carboplatin, given at 3-4 week intervals.
• Participants without SR seeding and < partial response after 2 cycles VT will receive 6 courses of vincristine-carboplatin-etoposide (VCE), given at 3-4 week intervals.
• Participants with extensive sub-retinal (SR) seeding will receive two up-front courses of subconjunctival (also called subtenon or periocular) CARBOplatin and systemic topotecan, given at 3-4 week intervals.
• Participants with SR seeding: > or equal to partial response after 2 cycles will receive three additional courses of vincristine-topotecan, and six courses of vincristine-carboplatin, given at 3-4 week intervals.
• Participants with SR seeding: < partial response after 2 cycles will receive 6 courses of VCE, given at 3-4 week intervals.

Focal treatments will be administered at the discretion of the treating team. Focal therapies will include cryotherapy, laser photocoagulation, thermo-therapy and plaque radiotherapy.

STRATUM C:

Participants with unilateral (unifocal or multifocal) advanced (R-E IV-V and IC D-E) intraocular disease will undergo enucleation. Adjuvant therapy will be based on histopathology:

• low risk participants: Participants in whom the enucleated eye does not show extra-retinal disease (see definition of intermediate and high risk below); will not receive any additional treatment.
• intermediate risk participants: Participants in whom the enucleated eye shows presence of tumor in the anterior chamber, invasion of the ciliary body/iris, massive invasion of the choroid, and invasion of the optic nerve beyond the lamina cribrosa with concomitant invasion of the choroid, will receive 4 courses of adjuvant chemotherapy with vincristine-carboplatin-doxorubicin (VCD).
• high risk participants: Participants in whom the enucleated eye shows involvement of the sclera, or involvement of the optic nerve at the level of the cut-end, will be treated with 6 courses of chemotherapy, with alternating courses of VCE and VCD.
• High-risk participants with extra-ocular extension (i.e. tumor extending beyond the sclera/cornea or beyond the cut end of the optic nerve) will be candidates for external-beam radiation therapy (EBRT) to the entire orbit, including the optic nerve, administered after 2 or 3 courses of treatment. Patients with extra-ocular extension may be considered for enrollment on an alternative therapeutic protocol for metastatic retinoblastoma (or best clinical management).

STRATUM D:

Management of participants with bilateral retinoblastoma is often complex; and some participants will have one eye enucleated upfront due to advanced disease. The decision for enucleation will be made after thorough consideration by the treating team. The treatment of the remaining eye will depend on a combination of two factors: a) R-E group of the remaining eye, and b) Histology of the enucleated eye. Though we have accumulated some information regarding the use of vincristine, cyclophosphamide, and doxorubicin in the treatment of intraocular retinoblastoma, it is not considered standard of care. Therefore, participants with intermediate and high risk features will be treated with 6 courses of vincristine, carboplatin, and etoposide (VCE). Those participants in whom the enucleated eye shows only low risk histology will be eligible to proceed with either stratum A or stratum B therapy. For those receiving stratum B therapy, consideration of periocular carboplatin will be allowed. External beam or proton beam radiation therapy will be considered for patients with extra-ocular extension.

Focal treatments will be administered at the discretion of the treating team. Focal therapies will include cryotherapy, laser photocoagulation, thermo-therapy and plaque radiotherapy.

Inclusion criteria

• Newly diagnosed, untreated intraocular retinoblastoma. Participants previously diagnosed with unilateral retinoblastoma treated surgically, with focal therapy or needing chemotherapy who develop asynchronous involvement of the contralateral eye, or patients with unilateral retinoblastoma treated only with enucleation or focal therapy who develop asynchronous involvement of the contralateral eye, will be eligible for study.
• ECOG Performance Score must be ≤ 2 within two weeks prior to registration.
• Participants must have an adequate liver function, as defined by bilirubin ≤ to 3X upper limit of normal (ULN), and SGOT and SGPT ≤ to 3X ULN.
• Participants must have adequate renal function as defined by serum creatinine ≤ to 3X ULN for age.
• Legal guardians must sign an informed consent indicating that they are aware of this study, the possible benefits, and toxic side effects. Legal guardians will be given a signed copy of the consent form.

Exclusion criteria

• Previously treated participants.
• Presence of metastatic disease or gross (residual) orbital involvement
• Participants must not have an invasive infection at time of protocol entry.
• Inability or unwillingness of research participant or legal guardian/representative to give written informed consent.