Hemangiopericytoma is a rare type of soft tissue tumor that arises from pericytes, cells that surround blood vessels. This type of tumor is usually benign but can become malignant. Some synonyms for hemangiopericytoma include solitary fibrous tumor, pericytomatous tumor, angiopericytoma, and staghorn vascular tumor. These tumors often occur in the limbs, pelvis, and trunk but can also form in the head and neck. Hemangiopericytomas are difficult to diagnose due to their similarity to other types of tumors and their variable clinical behavior. Treatment involves surgical removal of the tumor, which can be challenging due to the tumor's propensity for invading surrounding tissues.