1. International Classification of Retinoblastoma
Group
Defining Features
Group A
Small tumors away from foveola and disc
Tumors < 3 mm and
Located at least 3 mm from foveola and 1.5 mm from the optic disc
Group B
All remaining tumors confined to the retina
All other tumors confined to retina not in Group A
Subretinal fluid < 3 mm from the base of tumor
Group C
Local subretinal fluid or seeding
Local subretinal fluid alone > 3 to < 6 mm from tumor
Vitreous seeding or subretinal seeding < 3 mm from the tumor
Group D
Diffuse subretinal fluid or seeding
Subretinal fluid alone > 6 mm from tumor
Vitreous seeding or subretinal seeding > 3 mm from tumor
Group E
Presence of poor prognosis features
More than 2/3 globe filled with tumor
Tumor in anterior segment or ciliary body
Iris neovascularization, neovascular glaucoma
Tumor necrosis, phthisis bulbi

2. Group A
Small tumor (≤ 3 mm) confined to the retina, distant from the foveola and optic nerve.

3. Tumor > 3 mm, confined to the retina
Group B
Tumor > 3 mm, confined to the retina

4. Small tumors (≤ 3mm), confined to the retina,
Group B
Small tumors (≤ 3mm), confined to the retina,
but in close proximity to optic nerve and foveola.

5. Tumor with localized subretinal fluid and local seeding
Group C
Tumor with localized subretinal fluid and local seeding

6. Tumor with diffuse seeding
Group D
Tumor with diffuse seeding

7. Tumor with diffuse subretinal fluid and subretinal seeding
Group D
Tumor with diffuse subretinal fluid and subretinal seeding

8. Tumor in anterior segment
Group E
Tumor in anterior segment

9. Recommended Treatment of RB
R-E Group
ABC Group
Focal Treatments
Chemotherapy
Radiation
I – II A + -
If PD
I – III B
VCR 0.05 mg/kg
CBP 18.6 mg/kg
X 2 – 6 courses
IV – V
C – D
+/- subtenon CBP x 3
CBP 14 mg/kg x 2
ETO 6 mg/kg x 2
X 6 courses
If massive seeding, consider early RT Vb E
Enucleation