In a child diagnosed with retinoblastoma, which finding on examination is MOST consistent with Reese-Ellsworth Group V (or IIRC Group E) — indicating eye at risk for enucleation?

• A Single tumour <3 disc diameters, at least 3 mm from disc and fovea
• B Multiple tumours confined to the retina, none >10 disc diameters
• C Single posterior tumour 2 mm from the optic disc without seeding
• D Massive tumour >4 disc diameters involving more than half the retina, with vitreous seeding ✓

Explanation

Reese-Ellsworth Group V (or International Classification of Retinoblastoma Group E) represents the most advanced intraocular disease — massive tumour(s) involving more than half the retina, vitreous and subretinal seeding, neovascular glaucoma, and opaque media — indicating the eye is at highest risk for treatment failure with globe-conserving therapy and enucleation is often required. Group A/I involves small (<3 DD) peripheral tumours with no seeding. Groups B-D/II-IV represent intermediate severity. The IIRC has largely replaced the Reese-Ellsworth classification for guiding chemotherapy decisions.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.