title: In vivo skin dose measurement in breast conformal radiotherapy.
abstract: OBJECTIVE
  Accurate skin dose assessment is necessary during breast radiotherapy to assure that the skin dose is below the tolerance level and is sufficient to prevent tumour recurrence. The aim of the current study is to measure the skin dose and to evaluate the geometrical/anatomical parameters that affect it.
  
  
  METHODS
  Forty patients were simulated by TIGRT treatment planning system and treated with two tangential fields of 6 MV photon beam. Wedge filters were used to homogenise dose distribution for 11 patients. Skin dose was measured by thermoluminescent dosimeters (TLD-100) and the effects of beam incident angle, thickness of irradiated region, and beam entry separation on the skin dose were analysed.
  
  
  RESULTS
  Average skin dose in treatment course of 50 Gy to the clinical target volume (CTV) was 36.65 Gy. The corresponding dose values for patients who were treated with and without wedge filter were 35.65 and 37.20 Gy, respectively. It was determined that the beam angle affected the average skin dose while the thickness of the irradiated region and the beam entry separation did not affect dose. Since the skin dose measured in this study was lower than the amount required to prevent tumour recurrence, application of bolus material in part of the treatment course is suggested for post-mastectomy advanced breast radiotherapy. It is more important when wedge filters are applied to homogenize dose distribution.
authors.affiliation: Medical Physics Research Centre, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Medical Physics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; Medical Physics Department, Omid Hospital, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Shokouhozaman
authors.initials: S
authors.lastname: Soleymanifard
authors.affiliation: Cancer Research Centre, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Radiation Oncology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Seyed Amir
authors.initials: SA
authors.lastname: Aledavood
authors.affiliation: Department of Medical Physics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Atefeh Vejdani
authors.initials: AV
authors.lastname: Noghreiyan
authors.affiliation: Medical Physics Research Centre, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Mahdi
authors.initials: M
authors.lastname: Ghorbani
authors.affiliation: Medical Physics Department, Omid Hospital, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Farideh
authors.initials: F
authors.lastname: Jamali
authors.affiliation: Comprehensive Cancer Centres of Nevada, Las Vegas, Nevada, USA.
authors.forename: David
authors.initials: D
authors.lastname: Davenport
keywords: breast cancer; conformal radiotherapy; in vivo dosimetry; skin dose