Conformal fields in prostate radiotherapy: a comparison between measurement, calculation and simulation

• Published in: Journal of cancer research and therapeutics 2012-01, Vol.8 (1), p.34-39
• Main Authors: Mahdavi, Seied R, Rezaeejam, Hamed, Shirazi, Alireza, Hosntalab, Mohammad, Mostaar, Ahmad, Motamedi, Mohsen
• Format: Article
• Language: English
• Subjects: Care and treatment; Comparative analysis; Computer Simulation; Diagnosis; Humans; Male; Methods; Monte Carlo Method; Prostate; Prostate cancer; Prostatic Neoplasms - radiotherapy; Radiation therapy; Radiometry; Radiotherapy; Radiotherapy Dosage; Radiotherapy Planning, Computer-Assisted; Radiotherapy, Conformal; Reproducibility of Results
• ISSN: 0973-1482; 1998-4138
• DOI: 10.4103/0973-1482.95171

The objective of this study is to evaluate the accuracy of a treatment planning system (TPS) for calculating the dose distribution parameters in conformal fields (CF). Dosimetric parameters of CF's were compared between measurement, Monte Carlo simulation (MCNP4C) and TPS calculation. Field analyzer water phantom was used for obtaining percentage depth dose (PDD) curves and beam profiles (BP) of different conformal fields. MCNP4C was used to model conformal fields dose specification factors and head of linear accelerator varian model 2100C/D. Results showed that the distance to agreement (DTA) and dose difference (DD) of our findings were well within the acceptance criteria of 3 mm and 3%, respectively. According to this study it can be revealed that TPS using equivalent tissue air ratio calculation method is still convenient for dose prediction in non small conformal fields normally used in prostate radiotherapy. It was also showed that, since there is a close correlation with Monte Carlo simulation, measurements and TPS, Monte Carlo can be further confirmed for implementation and calculation dose distribution in non standard and complex conformal irradiation field for treatment planning systems.