Iveta Idzelytė1, Miglė Ivanauskaitė1
1Lithuania University of Health Sciences, Faculty of Medicine
Breast cancer is the most prevalent female malignancy in the world as well as Lithuania. Breast cancer holds third position in terms of mortality in Lithuania however in women aged 30-74 breast cancer is the leading cause of cancer death. 3-10% of breast cancer cases are hereditary, however BMI≥25kg/m2, first childbirth over 25, absence of breastfeeding after birth, late-onset menopause, use of oral contraceptives are the main risk factors of breast cancer. In 2004 Ministry of Health of the Republic of Lithuania passed a resolution which determined to perform mammography screening for women aged 50-69 once every two years in order to detect breast cancer in early stages and improve cancer outcomes. Breast cancer can occur at any age, so breast examination should be performed periodically. Diagnostic mammograms should be conducted after detection of possibly cancerous tumours. Breast ultrasonography is more efficient compared to mammography when the breast tissue is more dense which is more common in young women. However mammography is more efficient than ultrasonography overall. It is recommended to perform both mammography and breast ultrasound because the incidence rate of breast cancer is higher using both methods in women with more dense breast tissue. Mammograms and sonograms are evaluated using BI-RADS algorithm. The main descriptors of analysis are density of breast tissue, tumours and their features, lesion location, calcifications and breast asymmetry. Malignant tumour can be suspected if mammogram contains hyperdense tumour with irregular shape. In sonograms highly agressive tumours result in well defined masses with heterogenous echopattern and without posterior acoustic features. After assessment the category for the exam is assigned and further diagnostic strategy is provided.
Key words: breast cancer, diagnosis, screening, mammography, ultrasound.