Abstract
Congenital (infantile) hemangiopericytoma is a rare vascular tumor of infants. It has been recognized as having a benign clinical course, in contrast to the more malignant behavior of many hemangiopericytomas that occur in older children and adults. Twenty-four cases of congenital hemangiopericytoma have been reported in literature in Japan. Histopathologically, it often shows increased cellularity, prominent mitotic activity, and a foci of necrosis or hemorrhage. These histopathological findings are similar to malignant hemangiopericytoma in adults. Thus, congenital hemangiopericytoma is a problematic tumor because of the dissociation between the malignant histopathological findings and benign clinical courses. Herein, we reported a case of congenital hemangio-pericytoma in a neonate which showed malignant findings histopathologically and invaded to the surrounding tissues macro-grossly. However, only excision of tumor without any further treatment was performed. Follow-up examinations have shown no recurrence and no metastasis for 16 months since the excision.