Atretic encephalocele/myelocele: case reports with emphasis on pathogenesis

Atretic encephaloceles or myelomeningoceles are frequently solid due to hamartomatous proliferation of fibrous tissue and blood vessels. Because of the fibrous nature of the tumor with no cystic cavity and unusual location with no connection to CNS, they are frequently regarded as insignificant hamartomas. Apart from this terminology, they are also described as cutaneous meningiomas or hamartomas with ectopic meningothelial elements by the presence of meningothelial cells. We report a case of atretic encephalocele in the parietal scalp of an 8 year-old boy and a case of myelomeningocele in the posterior mediastinum of a 31 year-old woman. The terms atretic encephalocele and myelomeningocele are more appropriate for these cases because they include their pathogenesis and the non-neoplastic nature of the lesion.

Primary Cutaneous Meningioma arising from the Scalp: A case report

Primary cutaneous meningiomas are extremely rare tumors found in the cutis or subcutis, and generally have a benign course. The tend to be located on the scalp, face, neck. or paravertebral area. The primary cutaneous meningioma bears similarities to developmental defects and probably originates from arachnoid cell rests in the skin, although diverse groups of cutaneous meningiomas seem to arise from several different sources. A case of primary cutaneous meningioma occuring in the scalp of left parietal area of a 27-year-old female is presented. Clinically the lesion appeared as indolent, slow growing cutaneous mass and has no connection with underlying brain tissue, as determined by examination of the roentgenographs. The definite diagnosis was made after pathological examination. Microscopically the tumor is composed of sheets and nests of meningothelial cells. Immunohistochemical and electron microscopic studies reveal the typical findings of meningioma.