Breast cancer represents the leading cause of cancer and the second leading cause of death from cancer in females. Tamoxifen is widely used as an adjuvant therapy for postmenopausal breast cancer patients with positive oestrogen receptor proteins. Tamoxifen is known to be safe. However, it has been found to be associated with various endometrial pathologies. The aim of this study is to evaluate the role of each of conventional 2D ultrasound, Doppler studies, 3D ultrasound versus hysteroscopy and endometrial biopsy in comparison to each other, in screening and detection of endometrial pathologies in breast cancer patients treated with Tamoxifen.