In breast cancer patients, the ideal time sequences for chemotherapy and radiation therapy remain unknown. Most published trials were conducted including patients with early breast cancer. This retrospective analysis directed at evaluating the optimal sequence in the population for chemotherapy and radiotherapy. Chemotherapy and radiation therapy are typically not administered simultaneously in breast cancer patients due to the extensive use of Anthracyclinebased chemotherapy regimens and concernsabout excessive radiation toxicity with simultaneous treatment. Therefore, the best way to sequence systemic and radiation therapies is to yet to decide. This question occurs for both lumpectomy-treated patients and mastectomy-treated patients, but the ideal sequencing of adjuvant chemotherapy and radiotherapy in breast cancer patients remains contentious.To date, there is no clear benefit in breast cancer treatment for any radio- and chemotherapy sequence. In our study, Chemotherapy is suggested before radiotherapy regarding disease-free survival and toxicity of therapy, but decisive information on the appropriate sequence is uncommon. Radiotherapy (RT) increases local control and breast cancer-specific survival after surgery for localized breast cancer. Adjuvant chemotherapy (CT) increases a 15-year survival in patients at danger of harboring micro-metastatic illness. This can be verified after mastectomy in our retrospective assessment in high-risk patients. The sequential method is suggested to consider reduced toxicity and survival rates according to present rules.