Diffuse Infiltrating Retinoblastoma With Central Nervous System Metastasis

Abstract

Comment. Both MEB disease and Walker-Warburg syndrome have underlying deficiencies in posttranslational glycosylation of ␣-dystroglycan 3 that lead to severe defects in organogenesis and neuronal migration. Brain and eye phenotypes in MEB disease and Walker-Warburg syndrome likely involve defective glycosylation in proteins other than ␣-dystroglycan since chimeric mice deficient in ␣-dystroglycan develop congenital muscular dystrophy but not brain or eye phenotypes of MEB disease or Walker-Warburg syndrome. 7 In both diseases, there can be hypoplasia of the retina, choroid, optic nerve, and iris. 1,2,8 Specifically, Zervos et al 5 performed a histopathologic examination of 2 siblings with MEB disease and found loss of the inner nuclear layer, thinning of the outer nuclear layer, absence of rod and cone outer segments in midperipheral portions of the retina, and localized nerve fiber layer schisis nasal to the optic nerve head. They also noted focally atrophic retinal pigment epithelium and diffuse choroidal atrophy. 5 In our patient, with genetic testing results supportive of an MEB disease diagnosis, we describe the previously unreported clinical findings in early disease. A peripheral avascular retina led to extraretinal fibrovascular proliferation with subsequent contracture and combined tractional and rhegmatogenous retinal detachment with multiple perforating holes in the right eye. The underlying defect in glycosylation in MEB disease, which results in a severe defect in neuronal migration and possibly in hypoplasia of various structures, may be the cause of these retinal findings.

Retinoblastoma: Recent trends A mini review based on published literature

“…[11–14] This is a separate type of diffuse infiltrating RB. The imaging modalities such as ultrasound biomicroscopy and anterior segment optical coherence tomography are useful for such cases.…”