The Effect of Breast Reconstruction Prosthesis on Photon Dose Distribution in Breast Cancer Radiotherapy

Document Type: Original Paper

Authors

1 Department of Biomedical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran

2 Dept. of Medical Physics, Faculty of Medicine, Iran University of Medical Sciences

3 Associate Professor, Department of Radiotherapy and Oncology, Shaheed Beheshti University of Medical Sciences, Tehran, Iran

4 Department of Medical Physics, Tehran University of Medical Science, Tehran, Iran

Abstract

Introduction: Siliconeprosthetic implants are commonlyutilizedfor tissue replacement and breast augmentation after mastectomy. On the other hand, some patients require adjuvant radiotherapy in order to preventlocal-regional recurrence and increment ofthe overall survival. In case of recurrence, the radiation oncologist might have to irradiate the prosthesis.The aim of this study was to evaluate the effect of silicone prosthesis on photon dose distribution in breast radiotherapy.
Materials and Methods: The experimental dosimetry was performed using theprosthetic breast phantom and the female-equivalent mathematical chest phantom. A Computerized Tomographybased treatment planning was performedusing a phantom and by CorePlan Treatment Planning System (TPS). For measuring the absorbed dose, thermoluminescent dosimeter(TLD) chips (GR-207A) were used. Multiple irradiations were completed for all the TLD positions, and the dose absorbed by the TLDs was read by a lighttelemetry (LTM) reader.
Results: Statistical comparisons were performed between the absorbed dosesassessed by the TLDs and the TPS calculations forthe same sites. Our initial resultsdemonstratedanacceptable agreement (P=0.064) between the treatment planning data and the measurements. The mean difference between the TPS and TLD resultswas 1.99%.The obtained findings showed that radiotherapy is compatible withsilicone gel prosthesis.
Conclusion: It could be concludedthat the siliconbreast prosthesis has no clinicallysignificant effectondistribution of a 6 MV photon beam for reconstructed breasts.

Keywords

Main Subjects


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Volume 14, Issue 4
November and December 2017
Pages 251-256
  • Receive Date: 28 February 2017
  • Revise Date: 01 May 2017
  • Accept Date: 04 July 2017