Case report of a newborn with a posterior thoracic midline congenital hemangiopericytoma of the back.

The posterior thoracic midline location is an unusual site for a congenital hemangiopericytoma. The authors report such a case that caused near fatal exsanguination of a newborn after vaginal delivery. Magnetic resonance imaging (MRI) studies of the mass were completed after hemostasis. These studies showed a well-defined border between the tumor and underlying trapezius muscle. The mass was removed successfully surgically and presumed initially to be a teratoma. Pathological diagnosis of the tumor was hemangiopericytoma with low malignant potential. After a 9-day hospital course, the patient was discharged with recovering hepatic and renal function.