Medulloepithelioma Histopathology of medulloepithelioma showing characteristic neural tube like strands. Specialty Neurosurgery , oncology Medulloepithelioma is a rare, primitive, fast-growing brain tumour thought to stem from cells of the embryonic medullary cavity . [1] Tumours originating in the ciliary body of the eye are referred to as embryonal medulloepitheliomas, [1] or diktyomas . [2] A highly malignant undifferentiated primitive neuroepithelial tumour of children, medulloepithelioma may contain bone , cartilage , skeletal muscle , and tends to metastasize extracranially. [2] Contents 1 Signs and symptoms 2 Diagnosis 2.1 Classification 3 Treatment 4 Prognosis 5 Epidemiology 6 References 7 External links Signs and symptoms [ edit ] Medulloepithelioma have been reported to occur in the cerebral hemispheres , brainstem , cerebellum , and peripheral sites . [3] [4] [5] [6] Due to rapid growth of the tumour, patients typically present with increased intracranial pressure , seizures , and focal neurologic signs . [7] Diagnosis [ edit ] Neuronal differentiation, ranging from neuroblasts to ganglion cells, is seen in some medulloepitheliomas. Imaging studies such as Computerized Tomography (CT) and Magnetic Resonance Imaging (MRI) can aid diagnosis . Medulloepithelioma appears isodense or hypodense with variable heterogeneity and calcification on non-contrast CT scan, and enhances with contrast. [3] This radiographical finding is consistent with a primitive neuroectodermal tumour, especially in children. [6] Blood studies and imaging studies of the abdomen may be used to detect metastases. [6] Needle aspiration biopsy can be used to aid diagnosis. [6] Definitive diagnosis requires histopathological examination of surgically excised tumour tissues. Histologically, medulloepithelioma resemble a primitive neural tube and with neuronal, glial and mesenchymal elements. [8] [9] Flexner-Wintersteiner rosettes may also be observed. [10] Immunohistochemically , neural tube-like structures are vimentin positive in the majority of medulloepitheliomas. [11] Poorly differentiated medulloepitheliomas are vimentin negative.
