ABSTRACT
Meningothelial hamartomas represent a collection of meningothelial elements in ectopic skin lesions. They present as a tan-gray, red, flesh-colored papule or nodule with alopecia on the scalp. Histologically, there are numerous thin-walled pseudovascular spaces lined by meningothelial cells with psammoma bodies and collagen bodies. The meningothelial cells are immunopositive for vimentin and epithelial membrane antigen (EMA). We report two cases of meningothelial hamartomas. A 16-year-old boy had a skin-colored nodule with alopecia on the midline of the occipital area. Histopathologic examination showed meningothelial cells in collagen fibers, and these cells formed pseudovascular spaces. Immunohistochemical staining was positive for EMA. Brain MRI showed no abnormality in skull or brain parenchyma. Our other patient was a 1-month-old girl who had a depressed alopecic plaque on the central line of the occipital area. Skin biopsy showed a pseudovascular space consisting of meningothelial cells, which were positive for EMA. There was no gross abnormality of the skull or brain parenchyma.