Diffuse infiltrating retinoblastoma > >

Ocular and General History  5 years old boy  Unremarkable birth history (BBW: 2800g, full-term)  No preceding trauma or ocular history

First Presentation  Chief complaint:  Whitish materials in the left eye for 4 days  VA: 20/20 OD, 20/70 OS  IOP: 17mmHg OD, 34mmHg OS  Anterior segment OS:  White iris nodules, pseudohypopyon, large white KPs  Fundus OS:  Snowballs + snowbanking vit. opacity

Investigations - Lab  Complete blood count: negative  CRP/ESR: negative  Serology: negative  Syphilis, mycoplasma, toxoplasma, CMV, HSV, EBV  Autoimmune markers: negative  ANA, RF, anti-dsDNA, HLA-B27

Investigation - Image  Chest x-ray: normal  B-scan  Presence of vitreous opacity  No mass or calcification  Orbital CT scan  Fusiform soft tissue density at inferior region of globe  No calcification

Probable differential diagnosis  Granulomatous panuveitis OS, complicated with IOP elevation  nature?

Treatment  Empirical treatment  Topical steroid (prednisolone acetate 1% oph susp QID)  Antiglaucoma medication (dorzolamide 2% oph susp BID)  Long-acting cycloplegics (atropine 0.5% eye drops BID)

Second presentation: 4 weeks later  Persistant elevation in IOP: 37mmHg OS  Increase in pseudohypopyon  Mild decrease in iris nodules and keratic precipitates

Revised differential diagnosis  Masquerade syndrome, retinoblastoma highly suspected

Consequences  Direct enucleation of left eye without fine needle aspiration biopsy  Histopathological diagnosis:  poorly differentiated retinoblastoma with tumor invasion involving retina, choroid, sclera, ciliary body, trabecular meshwork, iris, corneal endothelium

HE stain, 400X

HE stain, 40X HE stain, 100X sclera TM Ciliary body irisiris lens Corneal endothelium Optic nerve

Final Diagnosis  Diffuse infiltrating retinoblastoma OS  An atypical presentation of retinoblastoma  Lack of discrete retinal mass or calcification  Extensive seeding of tumor cells into vitreous and anterior chamber producing an inflammatory appearance mimicking uveitis  Patient presented at an older age than the typical retinoblastoma patients

Conclusion  Retinoblastoma can present in a diffuse infiltrating pattern in rare cases  Keep this differential diagnosis when encountering pediatric patients presenting with an atypical uveitis