Abstract
Breast cancer is the most common cancer type among women according to the World Health Organization data. While breast-conserving surgery has been increasingly performed in patients with early-stage breast cancer, unilateral or bilateral mastectomy is still performed in many patients. With the changes in mastectomy techniques and the development of breast reconstruction techniques over the years, today the aim of breast reconstruction is to create breast tissue in a shape and symmetry that will correct the anatomical defect that occurs after mastectomy, without affecting the patient's oncological treatment. Radiotherapy is applied to patients after breast-conserving surgery as well as selected patient groups after mastectomy. In addition, reconstruction methods can be recommended after mastectomy in a patient who has previously received radiotherapy treatment to the breast. The aim of radiotherapy is to improve local and regional control and increase survival rates. Radiotherapy will affect the expected cosmetic outcomes. Poor cosmetic results can be prevented by determination of correct surgical technique, reconstruction strategy, and new developing technologies.