Figure 3: Typical treatment plan for IMRT technique of Hemangiopericytoma of the right temporal- apical cerebra in (A) axial view, (B) sagittal view, (C) coronal view, and (D) dose-volume histogram (DVH). The patient received postoperatively radiation therapy by IMRT technique consisting of 59.4 Gy in 1.8 Gy per fraction in total 33 fractions in continuous irradiation using Linac with 6MV-X rays (Varian 21 EX). The area to be irradiated is determined by correlating preoperative imaging studies, intraoperative findings, and the pathological review of the type. The target volume was generally defined as the tumour bed. For macroscopic residual tumours, the planning target volume (PTV) included the area of contrast enhancement adding a safety margin of 10–20 mm. The 95% PTV isodose line encompassed the target volume.