Intraocular medulloepithelioma: an unusual and challenging entity in paediatric population

Intraocular medulloepithelioma is a rare, congenital tumour of the non-pigmented ciliary epithelium. It most frequently arises from the ciliary body but can also have its origin from the retina, iris and optic nerve. The age when lesion first appears is typically around 2-10 years. Nearly 50-60% of patients having this lesion may also have secondary features such as cataract and neovascular glaucoma. Those with extrascleral medulloepithelioma are at risk for metastasis. Systemic correlation of the tumour with pleuropulmonary blastoma/DICER1 gene is reported in the literature. Here, we report a case of a 15 years old boy with one year history of right eye proptosis and painful red right eye along with decreased vision for one week. He was assessed and operated for cataract elsewhere three years back. The ophthalmology team managed him for endophthalmitis with intravenous antibiotics, followed by 2 sessions of cryotherapy and finally an enucleation of right eye was performed due to severe pain and no vision in the involved eye. His left eye, general physical examination and systemic evaluation were normal. Histopathology revealed the diagnosis of 'malignant teratoid medulloepithelioma'. Therefore, evaluation of systemic associations for DICER1 gene mutations was performed by the oncology team. For high risk feature of scleral invasion on histopathology, he was treated with chemotherapy. Since the tumour is of rare occurrence; an international expert team with vast research experience in PPB/DICER1 associated tumours was also contacted. He was registered in International PPB/DICER1 registry where a detailed central radiology and pathology review was performed. Genetic counseling and surveillance plan was also suggested by the international registry.