Breast Diseases in Pregnant Women: Possibilities of Ultrasound Diagnostics

Abstract

Mammary glands undergo significant physiologic changes during pregnancy and lactation in response to the increase in circulating hormone levels. Ultrasound is the first-line test for palpable breast masses in pregnant or breastfeeding patients. US images of normal breasts may vary depending on terms of pregnancy and duration of lactation. In the first trimester, the breast structure in a pregnant woman may be similar to the nonpregnant state: glandular tissue prevails, with clear granularity and narrow lactiferous ducts. In the second trimester, glandular tissue becomes more thick achieving 25–30 mm, the structure of parenchyma becomes more granular and diffusely hypoechoic due to increase of fat-free fibroglandular component, lactiferous ducts are about 3 mm wide, and vascularization of the parenchyma may be enhanced. At term, a diffuse duct ectasia of various degrees can be noted. During the entire lactation period, parenchyma is hyperechoic with significantly dilated (>3 mm) lactiferous ducts in grayscale images. Hypervascularized parenchyma shows in color imaging. During pregnancy and lactation, the mammary gland is subject to a number of specific changes, which can lead to the appearance of certain disorders, including benign changes that are associated with physiological changes in the body during pregnancy/lactation: inflammatory and infectious changes, juvenile papillomatosis, benign tumors, and malignant tumors. Specific features of breast cancer associated with pregnancy are usually aggressive in course, late diagnosis, and poor prognosis. The primary diagnosis, clinical stage, and extent of breast cancer in pregnant women in 85% are based on US findings.