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Ophthalmic Tumours
Retinoblastoma (ICD‐O‐3 C69.2) Rules for Classification In bilateral cases, the eyes should be classified separately. The classification does not apply to complete spontaneous regression of the tumour. There should be histological confirmation of the disease in an enucleated eye. The following are the procedures for assessing T, N, and M categories: T categories Physical examination and imaging N categories Physical examination M categories Physical examination and imaging; examination of bone marrow and cerebrospinal fluid may enhance the accuracy of appraisal
Regional Lymph Nodes The regional lymph nodes are the preauricular, submandibular, and cervical lymph nodes.
TNM Clinical Classification T – Primary Tumour TX Primary tumour cannot be assessed. T0 No evidence of primary tumour.
T1 Tumour confined to the retina with subretinal fluid no more than 5 mm from the base of any tumour, without retinal detachment T1a No tumour in either eye is greater than 3 mm in largest dimension or located closer than 1.5 mm to the optic nerve or fovea T1b At least one tumour is greater than 3 mm in largest dimension or located closer than 1.5 mm to the optic nerve or fovea. No retinal detachment or subretinal fluid beyond 5 mm from the base of the tumour T2 Tumours with vitreous or subretinal seeding or retinal detachment T2a tumour with subretinal fluid more than 5 mm from the base of any tumour T2b Tumour with vitreous and/or subretinal seeding T3 Severe intraocular disease T3a Phthisis or prephthisis bulbi