Intravascular Fasciitis- A Rare Lesion In The Maxillofacial Region

Objectives: To describe a fully documented new case and discuss differential diagnosis. Methods: case report with imaging and immunohistochemistry Results: a 58-years-old female presented an asymptomatic, slowly growing mobile buccal mass. A previous drainage attempt and a course of antibiotics had failed. There were no findings on a panoramic radiograph. CT scan identified a well defined, hypodense 1.7 cm soft tissue mass between the mental foramen and the masseter, involving the submucosal fat, with no evidence of bone involvement. V3 neurologic deficits were ruled out. The lesion was excised and submitted for pathological analysis. Sections exhibited a well defined hypercellular nodular mass, partly proliferated within the lumen of a large blood vessel. Bland spindle cells were seen in a densely vascularized, focally myxoid matrix, with rare mitotic figures. The nuclei were blunt-edged, vesicular, with poorly defined cytoplasm. IHC stains showed strong diffuse positivity for SMA. CD34 and CD31 emphasized the rich capillary bed, but were negative in the spindle cells. Bcl-2 was focally positive, Ki67 was positive in 10% of cells. Desmin, pankeratin, EMA, S-100, caldesmon and p53 were all negative, indicating a benign myofibroblastic origin. A diagnosis of intra-vascular fasciitis was established. Healing was uncomplicated and follow-up is ongoing. The 3 previously reported cases of IVF occurred in the buccal mucosa as well, with similar microscopic and clinical features. Conclusion: Rare cases of intra-vascular fasciitis, a variant of nodular fasciitis, are reactive pseudo-tumors which can mimic sub-mucosal tumors of the oral mucosa.