Anaplastic hemangiopericytoma manifesting as a rapidly enlarging extracranial mass lesion

We, herein, present a patient with a recurrent anaplastic hemanigiopericytoma manifesting as a rapidly enlarging extracranial mass lesion, which was revealed by pathological and intraoperative findings. In practice, this case highlights the mandatory need for a careful long-term follow-up for patients with hemangiopericytoma, since recurrence with a greater degree of malignancy can develop following an extended disease-free interval, as such knowledge will be helpful for planning the optimal surgical procedures.