Breast cancer is the most common type of cancer and the second leading cause of cancer mortality in women. Although its incidence continues to rise, mortality has declined over the past several years attributed to both early diagnosis and more effective treatment. Breast cancer strikes women of all ages, races, socioeconomic strata, and geographic localities. Cancer staging is essential in determining the choice of therapy, as well as a patient’s prognosis and chances for survival. The clinical application of PET /CT in breast cancer will help to choose the appropriate treatment, in the evaluation of treatment response by directly defining metabolic and morphological changes to discriminate responders from non-responders more accurately with an accuracy of 88–91% after the second course of chemotherapy. The goal of the study is to assess the role of FDG-PET/CT in detection of loco-regional recurrence in intact breast with identification of distant metastases and monitoring the response to therapy to define responders from non-responders to treatment in breast cancer.