Background: The diagnosis of breast cancer requires sensitive and specific examinations to detect the lesion and avoid surgical intervention in benign lesions. Moreover, therapeutic planning requires accurate preoperative evaluation of tumor extent and detection of multicentric and multifocal lesions. Aim of Study:This study aimed to assess the diagnostic accuracy of CT and Isotope scan in detection of breast cancer and their metastatic lesions.Patients and Methods: This study included 38 female patients who were referred from Oncology Center of Mansoura University and Outpatient Surgery Clinic based on physical finding of palpable breast masses. All patients underwent clinical history and examination, Ultrasound and mammography, Contrast enhanced CT, Isotope scan and SPECT / CT fusion technique if available.Results: Contrast enhanced CT, mammography, and US are 100% specific for diagnosis of malignant mass but they differ in their sensitivity that was 88% for mammography, 97% for US and 100% for post-contrast CT. Comparison of the area under the ROC curve of the perfect post-contrast CT versus the two other modalities revealed that the difference was statistically significant when comparing it with mammography (p=0.0351) but it was not statistically significant when comparing it with US (p=0.2787).Conclusions: CT mammography proved high efficacy in detection of solitary primary and bilateral masses. It has the advantage of wide images scope to detect LNs as well as other skin and chest wall lesions. We indicated in our study to do bone scan and whole body CT for all patients of breast cancer as combination between them which proved highly sensitivity and specificity in detection of primary breast masses as well as metastatic lesions.