- - - PhD, Medical Physics Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- - - PhD, Department of Biomedical Engineering and Medical Physics, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- - - MSc, Medical Physics Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- - - PhD, Department of Medical Physics, Royal Adelaide Hospital, Adelaide, South Australia
- - - MSc, Medical Physics Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- - - MSc, Department of Medical Physics, Reza Radiation Oncology Center, Mashhad, Iran
- - - MD, Department of Medical Physics, Reza Radiation Oncology Center, Mashhad, Iran

Background: Skin is a sensitive organ and should be spared in radiotherapy and irradiation of skin in radiotherapy can cause to acute and late skin effects such as erythema, desquamation, epilation, color change, or even necrosis. Objective: The aim of the present study is to do skin dosimetry in radiotherapy of parotid cancer using Gafchromic EBT۳ radiochromic film. EBT۳ radiochromic films were calibrated in ۰.۲-۵ Gy dose range.Material and Methods: This is an experimental study in the field of radiotherapy physics. Treatment planning was performed on a RANDO phantom for treatment of parotid cancer by a clinical oncologist. Based on the treatment planning, the skin dose at various points in the overlapping region of right anterior-oblique and right posterior-oblique fields were measured using EBT۳ radiochromic film. Results: The minimum and maximum skin doses in a fraction (with ۲.۰ Gy prescribed dose) were ۰.۵۰ Gy and ۰.۹۷ Gy, respectively. Based on these values, the total skin dose in ۳۰ treatment fractions (for removed tumor) or in ۳۵ treatment fractions (for unremoved tumor) was in the range of ۱۵-۳۳ Gy. Conclusion: Based on the skin dosimetry results of parotid cancer radiotherapy using EBT۳ films, it is predicted that there will occur mild skin reactions and these reactions can be neglected due to being mild.

Radiotherapy, Parotid, Neoplasms, Skin, Dosimetry, RadioChromic film