Multiple recurrence of an intracranial hemangiopericytoma.

The multiple multilocular intracranial recurrence of a hemangiopericytoma (HPC) over 21 years in our patient, who has been successfully operated upon and irradiated several times, confirms the known tendency of the majority of HPCs to marked biological activity. The aggressive behavior of HPCs shows an unusually broad scale of variations. On the basis of clinical observations of this particular case, the relative or potential malignancy of HPCs is discussed.