Table 33Reese-Ellsworth staging classification of retinoblastoma(411)

Group I: very favourable
ASolitary tumour smaller than 4 disk diameters (at or behind equator)
BMultiple tumours smaller than 4 disk diameters (at or behind the equator)
Group II: favourable
ASolitary tumour 4–10 disk diameters (at or behind equator)
BMultiple 4–10 disk diameters (at or behind equator)
Group III: doubtful
AAny lesion anterior to the equator
BSolitary tumours larger than 10 disk diameters behind the equator
Group IV: unfavourable
AMultiple tumours, some larger than 10 disk diameters
BAny lesion extending anteriorly to the ora serrata
Group V: very unfavourable
ATumours involving more than half the retina
BVitreous seeding

From: 20, Children’s and Young People’s Cancer

Cover of Referral Guidelines for Suspected Cancer in Adults and Children
Referral Guidelines for Suspected Cancer in Adults and Children [Internet].
NICE Clinical Guidelines, No. 27.
Clinical Governance Research and Development Unit (CGRDU), Department of Health Sciences, University of Leicester.
Copyright © 2005, National Collaborating Centre for Primary Care.

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