Background: People of various ages, races, financial backgrounds, and geographic areas are typically affected by breast cancer, which is the most common malignant disease in women. After a diagnosis of breast cancer, a precise assessment of tumor staging is necessary to establish the course of treatment and prognosis.

Aim: To investigate the role of 18F-FDG PET/CT in staging, pre-therapeutic metastatic workup or preoperative evaluation of newly diagnosed patients with breast cancer which subsequently affects their management.

Patients and methods: This cross sectional study included 30 female patients who had just been diagnosed with breast cancer and were referred for initial 18F‑FDG PET/CT scans for preoperative or pre-therapeutic staging. All patients underwent both CT and PET examinations for initial staging of breast cancer . The standard of reference was histopathology and 6 months follow-up

Results: PET/CT had higher sensitivity (92%) and specificity (80%) in diagnosis of nodal metastasis compared to conventional CT with lower sensitivity (64%) and specificity (60%). Also, PET/CT had higher sensitivity (94.4%) and specificity (75%) in diagnosis of distant metastasis compared to conventional CT with lower sensitivity (88.9%) and specificity (66.7%).

Conclusion: 18F-FDG PET/CT is a valuable technique that detects metastasis in newly diagnosed breast cancer patients in an efficient, accurate, and noninvasive manner, resulting in modification of the initial staging, which in turn reflected on the patients' therapeutic plans.