Abstract
A 62-year-old man presented with a tender, solitary nodule on the left upper arm. He had no specific family history of the lesion. A biopsy specimen showed various sized irregular vascular lumens in the upper dermis. The vascular walls consisted of an endothelial cell layer and rim of one to three layers of glomus cell nests outside the endothelial cells. The cell nests consisted of round shaped epitheloid cells with relatively uniform round or oval shaped nuclei and pale cytoplasm. These tumor cells were strongly positive for vimentin, and a-smooth muscle actin. On electron microscopic examination, the cytoplasm of these tumor cells contained fine filamentous components and many electron dense bodies were found at the plasma membrane and the cytoplasm. We report a case of a solitary glomus tumor(glomangioma) that showed the histological features of the multiple type of glomus tumor. In addition we describe the results of an immunohistochemical and electron microscopic study.