Assessment of brain dose distribution for ARC and conformal radiation therapy (CRT): A comparison study

Abstract

a b s t r a c tObjective: This study evaluates the dose distribution of the three-dimensionally planned conformal radiation therapy (CRT) compared to the previously used (5 years ago) arc radiotherapy (ARCRT) of the brain cancer patients in Clinical Oncology and Nuclear Medicine Department e Mansoura University.Patients and methods: Thirty-three unselected brain cancer patients were planned by both the standard CRT and ARCRT techniques for radiotherapy of the brain. Doseevolume histograms were carried out by the 3D treatment planning system. They were assessed for the GTV, CTV, PTV and organs at risk. The prescribed total dose was 60 Gy in 30 fractions.Results: Comparing different DVHs, it was found that, the GTV, CTV and PTV were adequately covered in both (CRT & ARCRT) plans while it was demonstrated that ARCRT produced superior distribution compared to CRT technique, with considerable sparing of organ at risk. Conclusion:The tangential beam ARCRT planning demonstrated a significantly better homogeneity index for the GTV, CTV, and PTV of the brain cancer patients with a significant reduction in the mean doses of the both eyes, optic nerves, optic chiasm and brain stem.