tailieunhanh - Báo cáo khoa học: "Doses to internal organs for various breast radiation techniques - implications on the risk of secondary cancers and cardiomyopathy"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Radiation Oncology cung cấp cho các bạn kiến thức về ngành y đề tài: Doses to internal organs for various breast radiation techniques - implications on the risk of secondary cancers and cardiomyopathy. | Pignol et al. Radiation Oncology 2011 6 5 http content 6 1 5 RADIATION ONCOLOGY RESEARCH Open Access Doses to internal organs for various breast radiation techniques - implications on the risk of secondary cancers and cardiomyopathy Jean-Philippe Pignol1 Brian M Keller2 Ananth Ravi2 Abstract Background Breast cancers are more frequently diagnosed at an early stage and currently have improved long term outcomes. Late normal tissue complications induced by adjuvant radiotherapy like secondary cancers or cardiomyopathy must now be avoided at all cost. Several new breast radiotherapy techniques have been developed and this work aims at comparing the scatter doses of internal organs for those techniques. Methods A CT-scan of a typical early stage left breast cancer patient was used to describe a realistic anthropomorphic phantom in the MCNP Monte Carlo code. Dose tally detectors were placed in breasts the heart the ipsilateral lung and the spleen. Five irradiation techniques were simulated whole breast radiotherapy 50 Gy in 25 fractions using physical wedge or breast IMRT 3D-CRT partial breast radiotherapy Gy in 10 fractions HDR brachytherapy delivering 34 Gy in 10 treatments or Permanent Breast 103Pd Seed Implant delivering 90 Gy. Results For external beam radiotherapy the wedge compensation technique yielded the largest doses to internal organs like the spleen or the heart respectively 2 300 mSv and Gy. Smaller scatter dose are induced using breast IMRT respectively 810 mSv and Gy or 3D-CRT partial breast irradiation respectively 130 mSv and Gy. Dose to the lung is also smaller for IMRT and 3D-CRT compared to the wedge technique. For multicatheter HDR brachytherapy a large dose is delivered to the heart Gy the spleen receives 1 171 mSv and the lung receives 2 471 mSv. These values are 44 higher in case of a balloon catheter. In contrast breast seeds implant is associated with low dose to most internal organs. Conclusions The .