Comparison of Different Techniques in Breast Cancer Radiotherapy Planning

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