ABSTRACT

This study aimed to minimize the radiation dose to organs other than the target tissue during adjuvant therapy applied for breast cancer, by using different planning methods.

30 women with T1-2 N1-3 M0 breast cancer were included in the study. Planning was performed using four different methods to the supraclavicular area, internal, and external tangential fields. All planning was done in a virtual environment by and the requested data was obtained. All patients were treated by the 1st method. Method 1: Different isocenter, complete supraclavicular area, breast half beam. Method 2: Different isocenter, half supraclavicular area, breast half beam. Method 3: Single isocenter, half supraclavicular area, breast half beam. Method 4: Different isocenter, supraclavicular area full beam, breast full beam.

Evaluation of PTV values showed a statistically significant reduction in D-max, 110% and 115% values by method III. Lower doses in other parameters were not statistically significant.

Based on these results, the application of single isocenter, 3D radiotherapy in breast cancer provides significant advantages especially in PTV and pulmonary dosages.