Hemangiopericytoma presenting as a congenital midline nasal mass.

Hemangiopericytoma is a rare tumor that is thought to originate from the vascular pericytes of Zimmerman. Although they represent less than 1% of all vascular neoplasms, 15% to 30% of these tumors are found in the head and neck. The benign or malignant nature of a hemangiopericytoma is determined clinically, not histologically, indicating the need for close and careful follow-up. We describe a congenital midline nasal mass in a 2-year-old boy that proved to be a hemangiopericytoma. Clinical photographs, a magnetic resonance imaging scan, and histologic photographs depict the findings. The evaluation and differential diagnosis of midline nasal masses are discussed.