Sclerosing perineurioma: a clinicopathological study of five cases and diagnostic utility of immunohistochemical staining for GLUT1

We reviewed five cases of sclerosing perineurial tumor of the hand. Four patients were male and one was female with ages ranging from 11 years to 49 years (mean 26 years). The predominant reason for consultation at the outpatient clinic was a slowly growing painless mass. The sites of involvement were the thumb in two cases, and the ring finger, middle finger and palm in one case each. The lesions were hard and firm, well-circumscribed white masses with a fibrous consistency ranging from 1.2 cm to 4.0 cm (mean 2.5 cm) in maximum dimension. Microscopically, all the tumors were composed of thick collagen and variable numbers of small, epithelioid cells exhibiting corded, trabecular and whorled growth patterns. Electron microscopy showed long cytoplasmic processes with a discontinuous basal lamina and occasional pinocytotic vesicles in the tumor cells. Immunohistochemically, most of the tumor cells were positive for epithelial membrane antigen, vimentin, collagen type IV and CD10, but not for S-100 protein, CD34, desmin and cytokeratin. We also observed that the tumor cells were positive for the human erythrocyte glucose transporter (GLUT1) antigen, suggesting that GLUT1 may be a useful marker for the identification of sclerosing perineurioma.