Table 1 of
Azimi, Mol Vis 2022; 28:130-146. Table 1 of
Azimi, Mol Vis 2022; 28:130-146.
Table 1. Classification systems for intraocular retinoblastoma.
| Eye Group | IIRC | ICRB | Therapy |
|---|---|---|---|
| A (very low risk) | All tumors are 3 mm or smaller, confined to the retina, and at least 3 mm from the foveola and 1.5 mm from the optic nerve. No vitreous or subretinal seeding is allowed | 3 mm or smaller in greatest dimension Small tumors confined to the retina tumors are not near the foveola (the central “pit” of the retina) or the optic nerve No vitreous or subretinal seeding No retinal detachment | Laser photocoagulation Thermotherapy Cryotherapy Plaque radiotherapy |
| B (low risk) | Eyes with no vitreous or subretinal seeding Discrete retinal tumor of any size or location. Retinal tumors may be of any size or location not in group A Small cuff of subretinal fluid extending ≤5 mm from the base of the tumor | Larger tumor a. One or more tumors are >3 mm b. Macular location Tumor located ≤3 mm from fovea c. Juxtapapillary location Tumor located ≤1.5 mm from optic disc d. Additional subretinal fluid, Presence of subretinal fluid ≤3 mm from tumor margin Tumors are only in the retina No vitreous seeding No retinal detachment more than 5 mm from the tumor base | Laser photocoagulation Thermotherapy Cryotherapy Plaque radiotherapy Intravenous/intra-arterial chemotherapy |
| C (moderate risk) | Eyes with focal vitreous or subretinal seeding Discrete retinal tumors of any size and location. Any seeding must be local, fine, and limited so as to be theoretically treatable with a radioactive plaque Up to one quadrant of subretinal fluid may be present | Focal subretinal fluid or seeding a. Localized subretinal fluid greater than 3 mm and less than 6 mm from the tumor b. Vitreous or subretinal seeding less than 3 mm from the tumor There is retinal detachment and it is more than 5 mm from the tumor base | Intra-arterial chemotherapy Intravitreal chemotherapy |
| D (high risk) | Eyes with diffuse vitreous or subretinal seeding and/or massive, non-discrete endophytic or exophytic disease Eyes with more extensive seeding than Group C Massive and/or diffuse intraocular disseminated disease including exophytic disease and >1 quadrant of retinal detachment. May consist of ‘greasy’ vitreous seeding or avascular masses. Subretinal seeding may be plaque-like | Diffuse subretinal fluid or seeding a. Subretinal fluid greater than 3 mm from the tumor b. Vitreous or subretinal seeding greater than 3 mm from the tumor | Intra-arterial chemotherapy Intravitreal chemotherapy Enucleation |
| E (very high risk) | Eyes that have been destroyed anatomically or functionally with one or more of the following: Irreversible neovascular glaucoma, massive intraocular hemorrhage, aseptic orbital cellulitis, tumor anterior to anterior vitreous face, tumor touching the lens, diffuse infiltrating retinoblastoma and phthisis or pre-phthisis | Extensive tumor a. Tumor takes up more than 50% of the globe b. Neovascular glaucoma c. Opaque media from hemorrhage in anterior chamber, vitreous, d. or subretinal space e. Invasion of optic nerve, choroid (>2 mm), sclera, orbit or anterior chamber | Intra-arterial chemotherapy Enucleation Adjuvant intravenous chemotherapy if high-risk histopathological features present |