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What is Reese-Ellswoh classification is used for? and explain in detail?
Retinoblastoma REF: Decision Making in Radiation Oncology, Volume 2 by Jiade J. Lu page 1041 Repeat from June 2008 Reese-Ellswoh classification of Retinoblastoma: Type Description Group I "Very ourable" A Solitary tumor, less than 4 dd in size, at or posterior to the equator B Multiple tumors, none over 4 dd in size, all at or posterior to the equator Group II "Favourable" A Solitary tumor, 4-10 dd in size, at or posterior to the equator B Multiple tumors, 4-10 dd in size, all posterior to the equator Group III "Doubtful" A Any lesion anterior to the equator B Solitary tumors larger than 10 dd posterior to the equator Group IV "Unorable" A Multiple tumors, some larger than 10 dd B Any lesion extending to the ora serrata Group V "Very unourable" A Massive tumors involving over half the retina B Vitreous seeding *dd= disc diameter (approximately 1.5 mm)