Oral perineurioma: clinicopathologic features from two cases and review of literature.

The present study reports two cases of oral perineuriomas, including a clinicopathologic review of the 39 published cases (17 intraneural and 22 extraneural perineuriomas) in the English language literature. In the first case, the tumor occurred in an 84-year-old male as a painless, asymptomatic, 20-mm submucosal nodule on the right lower mucobuccal fold near to the premolar area. In the second case, a 46-year-old female presented with a painless, 25-mm, slow-growing, fibrous, pedunculated nodule on the right buccal mucosa. In the first case, the tumor was composed of spindle cells arranged in a storiform pattern, classified as intraneural perineurioma; and in the second, it was an extraneural perineurioma, showing a whorled myxoid stroma. Immunohistochemical analysis confirmed the diagnosis by showing positivity for vimentin, EMA, and Glut-1 in case 1 and EMA, Glut-1, Claudin-1, and CD34 (focally) in case 2. Complete surgical removal was performed for both tumors, and there was no evidence of local recurrence after a long-term follow-up.