[Meningothelial hamartoma of the scalp. A case report]

We report the case of a 34-year - old male with meningothelial hamartoma. The patient had a subcutaneous tumor of the scalp, clinically diagnosed as a lipoma. Histologically, the tumor consisted of mature connective tissue elements, adipose tissue, blood vessels and clusters of cuboidal or polygonal cells with scant eosinophilic or amphophilic cytoplasm and regular nuclei. Mitoses were absent. Immunohistochemically, these cells showed diffuse positivity for vimentin, epithelial membrane antigen (EMA) and progesterone receptors. Other markers examined, including α-smooth muscle actin, CD34, desmin, cytokeratin AE1/AE3, cytokeratin CAM 5.2, α-inhibin, estrogen receptors, synaptophysin, chromogranin A and S100 protein, were negative. Meningothelial hamartoma is a rare benign lesion known under many synonyms and the exact number of reported cases is difficult to establish.