Background: Breast lumps are localized swellings that feel different from the surrounding breast tissue. It is a symptom/sign for a variety of conditions. As approximately 10% of breast lumps ultimately lead to a diagnosis of breast cancer. Mammography and sonography are the standard imaging techniques for detection and evaluation of breast disease. Mammography is the most established screening modality. Especially in young women and women with dense breasts, sonography appears superior to mammography, and differentiation between solid tumors and cysts is easier. Sensitivity and specificity of sonography or mammography are higher if sonography and mammography are combined. The latest edition of BI-RADS does not use percentages. Factors that can increase breast density include hormone replacement therapy, the effect is greater with combination hormone therapy than with oestrogen therapy alone, pregnancy, lactation, weight loss from reduction of breast fat, breast cancer especially inflammatory breast cancer, inflammation as mastitis. Factors that can decrease breast density include, age, post-menopausal state, medications: e.g. Danazol , vitamin D and calcium intake in pre-menopausal women, increasing age, weight gain, acromegaly