Oral intravascular fasciitis: a rare maxillofacial lesion.

Nodular fasciitis is a benign non-neoplastic myofibroblastic proliferation, involving the head in 7% to 20% of cases. Intravascular fasciitis (IVF) is a rare variant, with a unique intravascular growth pattern. Only 4 maxillofacial cases have been previously reported. We describe a 58-year-old woman with a rapidly growing, hard, mobile buccal submucosal swelling. CT scans identified a well-defined, 1.7-cm isodense lesion, located between the mental foramen and masseter muscle, which was excised under general anesthesia. A well-defined cellular nodular mass was composed of bland spindle cells, in a densely vascularized, focally myxoid matrix, involving an arterial lumen, and extending into adjacent tissues. Mitoses were rare. Immunohistochemistry was positive for smooth muscle actin, negative for keratins, S-100, epithelial membrane antigen, caldesmon, p53 and Alk. CD31 and CD34 were positive only in the vascular component, supporting the diagnosis of intravascular fasciitis.