[Glial heterotopy of the nose ("nasal glioma"). Description of a case].

A six months female infant was admitted in our hospital for congenital dysmorphism of face: a subcutaneous nodule in left nose region was present. An x-ray study showed relevant scoliosis of the nasal septum. On surgery a white firm nodule was incompletely excised; a post-operatory CT-scan excluded any communication of neoplasia with brain. No bone lacunae were seen. Clinically there was neither rhinorrhea nor meningitis. The baby was discharged on 7th day. Grossly the mass presented white surface, firm consistency with small hemorrhages on cut surface. Microscopically the nodule, encircled by a fibrous pseudo-capsule, was mostly composed of gemistocytic astrocytes, occasionally binucleated, interspersed within fibrillary neuroglial tissue. Strands of fibrous tissue, in continuity with the pseudo-capsule, separated the glial tissue. No neuronal cells were seen. Necrosis, mitotic figures and vascular proliferations were absent. GFAP immunohistochemical stain confirmed the glial nature of the cells. Our diagnosis was one of "heterotopic glial tissue of nose" (nasal glioma). The absence of connection between the nodule and endocranial contents (CSF-filled spaces, leptomeningeal or dural tissue), excluded the diagnosis of encephalocele. In our case, the tissue was only of embryonic neuroectodermal derivation: on this basis the diagnosis of teratoma, which is classically composed of two or three embryonic layers could be excluded. The pathogenesis of nasal glioma is briefly discussed by authors.