Voluntary breath-hold reduces dose to organs at risk in radiotherapy of left-sided breast cancer.

Abstract

To compare the dose to organs at risk with free breathing (FB) or voluntary breath-hold (VBH) during radiotherapy of patients with left sided breast cancer. Radiotherapy reduces the risk of breast-cancer-specific mortality but the effects on other organs increase non-cancer-specific mortality. Radiation exposure to the heart, in particular in patients with left sided breast cancer, can be reduced by breath hold methods that increase the distance between the heart and the radiation field. Three-dimensional conformal radiotherapy (3D-CRT) dose plans for the left breast and organs at risk including the heart, left anterior descending coronary artery (LAD) and ipsilateral lung were compared with FB and VBH in ten patients with left sided breast cancer. The mean doses to the heart and LAD were reduced by 50.4 % (p<0.001) and 58.8 % (p=0.006), respectively, in VBH relative to FB. The mean dose to the ipsilateral lung was reduced by 13.8 % (p=0.11) in VBH relative to FB. The planning target volume (PTV) coverage was at least 95 % in both FB and VBH (p=0.78). The VBH technique significantly reduces the dose to organs at risk in 3D-CRT treatment plans of left sided breast cancer.