International Journal of Hematology and Oncology 2023, Vol 33, Num 4 Page(s): 191-197
Dosimetric Comparison of 3-Dimensional Conformal and Intensity-Modulated Radiotherapy Planning Techniques in Breast Cancer

Beyza SIRIN OZDEMIR1, Orkun KIRECCI2

1Akdeniz University Faculty of Medicine, Department of Radiation Oncology, Antalya, TURKEY
2University of Health Sciences, Tepecik Training & Research Hospital, Department of Nuclear Medicine, İzmir, TURKEY

Keywords: Radiotherapy, Breast cancer, 3DCRT, IMRT, Homogeneity index
Considering the high rates of long-term survival in breast cancer patients, it is crucial to determine the most appropriate RT technique in order to prevent RT-related heart and lung damage and other complications that may adversely affect quality of life. In this study, we aimed to detect the superior radiotherapy technique in patients with breast cancer in terms of the target volumes and the organ at risk (OAR). We included 20 breast cancer patients who were applied modified radical mastectomy. Two different treatment plans (IMRT and 3DCRT) were prepared for each patient. Chest wall, supraclavicular, axillary and/or mammaria interna lymphatic regions were contoured as clinical target volüme (CTV). For planning target volüme (PTV), 0.5 cm was added to CTV (post margin; 0.3 cm). The doses of the target volumes and the OAR volumes (contralateral breast, heart, ipsilateral lung), the homogeneity index (HI) were compared. For the heart, the contralateral breast, the ipsilateral lung, Dmean and V25, Dmean and Dmax, D5 and D20 were evaluated, respectively. In addition, D2, D98, D95 ve Dmean were investigated for the PTV. Mann Whitney test was used for statistical analysis and p< 0.05 was considered significant. IMRT technique was superior to the 3DCRT in terms of the PTV, the OAR volumes and the HI. However, irradiated contralateral breast volume was less in the 3DCRT technique.