Malignant Ocular Medulloepithelioma Diagnosed in an Adolescent Female at a Tertiary Health Facility in Southwestern Nigeria: A Case Report and Review of the Literature

Abstract

Introduction: Intraocular medulloepithelioma is a rare, nonhereditary neoplasm of childhood arising from primitive medullary epithelium, often involving the ciliary body. It is a slow-growing tumour and most patients present between 2 and 10 years of age with loss of vision, pain, leukocoria and/or conjunctival congestion. It is difficult to estimate the true incidence of this tumour because of its rarity and paucity of large-scale population-based studies. To the best of our knowledge, this is the first reported case of histologically diagnosed primary malignant ocular medulloepithelioma in Nigeria. Case presentation:We report the case of a 16-year-old female who presented with painful progressive left ocular swelling and visual deterioration of 8 years duration with associated redness and tearing. At presentation, a soft fleshy mass was seen protruding from the inferior aspect of the left eyeball, and enucleation of ocular contents was subsequently performed. Microscopic evaluation of the lesion showed distorted eye tissue with infiltration of the cornea, uveal tract and retina by malignant primitive neuroepithelial cells disposed in sheets, anastomosing cords and multiple classic Homer Wright rosettes with areas showing neuronal differentiation and marked nuclear atypia. The tumour also had a high mitotic index. The features seen were consistent with the diagnosis of a malignant teratoid medulloepithelioma. The patient had chemotherapy and radiotherapy and was subsequently discharged home for follow-up at the outpatient clinic. Conclusion:Primary intraocular medulloepithelioma is a rare neoplasm occurring usually in the first decade of life. Before this, no case has been reported from Nigeria, especially in an adolescent female. The mainstay of treatment is surgery with chemo-radiation. This case also highlights the challenges involved in arriving at a definitive diagnosis.