Neuronal differentiation, ranging from neuroblasts to ganglion cells, is seen in some<unk> s.Imaging studies such as Computerized Tomography (CT) and Magnetic Resonance Imaging (MRI) can aid diagnosis.<unk>  appears isodense or hypodense with variable heterogeneity and calcification on non-contrast CT scan, and enhances with contrast. This radiographical finding is consistent with a primitive neuroectodermal tumour, especially in children. Blood studies and imaging studies of the abdomen may be used to detect metastases. Needle aspiration biopsy can be used to aid diagnosis. Definitive diagnosis requires histopathological examination of surgically excised tumour tissues. Histologically,<unk>  resemble a primitive neural tube and with neuronal, glial and mesenchymal elements. Flexner-Wintersteiner rosettes may also be observed. Immunohistochemically, neural tube-like structures are vimentin positive in the majority of<unk> s. Poorly differentiated<unk> s are vimentin negative. Classification<unk>  was originally classified as the most primitive neoplasm of the Central Nervous System (CNS) by Bailey and Cushing in 1926. Rorke et al. classified this tumour into two subtypes: :1)<unk>  not otherwise specified :2)<unk>  with differentiation into astrocytes, oligodendrocytes; ependymal cells; neuronal cells; others (melanin, mesenchymal cells); and mixed cellular elements.
Medulloepithelioma
Lymphoepithelioma
Epithelioma
Pyogenic granuloma
Trichoepithelioma
Desmoplastic trichoepithelioma
Angiokeratoma
Nesidioblastoma