E1238. Got Milk? A Case-Based Approach to the Lactating Patient
  1. Sheila Maillard; University of Missouri Kansas City
  2. JulieAnn Stover; University of Missouri Kansas City
Starting with pregnancy, the breasts undergo numerous changes to prepare for the growth and development of the infant. The areola begins to darken, the breasts increase in size, and the Montgomery glands become more prominent. Societies like the American Academy of Pediatrics and the World Health Organization support and recommend breastfeeding for up to two years and beyond. Additionally, many women are now delaying childbirth. Finally, supply chain issues and recent recalls have created a nationwide formula shortage, altering breastfeeding goals. Lactating women now make up a larger proportion of patients imaged; hence, it is important for the radiologist to be aware of the diverse pathologies found in this population. This can range from simple issues such as lactating adenomas and galactoceles to complex and potentially devastating disease processes like pregnancy associated breast cancer (PABC), an entity that mainly occurs in the postpartum period.

Educational Goals / Teaching Points
This educational exhibit will embark on a multimodality, case-based approach through common and uncommon presentations within the lactating population, highlighting current American College of Radiology (ACR) recommendations for breast cancer screening in addition to the best approach for diagnostic workup. The goal ise to increase familiarity with image interpretation in the context of lactating breasts (aimed at residents, fellows, and practicing radiologists interested in breast imaging).

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
ACR guidelines for screening are the same regardless of lactational status: all patients of average or intermediate risk should begin annual screening at age 40. It is recommended that patients at high risk undergo annual breast MRI in addition to annual mammography, as data shows that breastfeeding is safe after administration of gadolinium-based contrasts. Due to the increased density of breast tissue in lactating women, breast ultrasound (US) is the first line imaging modality in lactating women presenting with a focal complaint. If breast ultrasound is negative, the patient will be instructed to undergo clinical follow up. If there are any suspicious sonographic findings, additional imaging with mammography/digital breast tomosynthesis (DBT) is indicated. After this workup, any suspicious imaging findings warrant further investigation with an image-guided core biopsy, and patients should be advised of the possible risk of milk fistula in addition to bleeding and infection. Dynamic contrast enhanced (DCE) MRI is recommended after biopsy-proven malignancy or to further evaluate pathologic nipple discharge.

Familiarity with imaging in lactating women can help the radiologist arrive at the appropriate assessment and recommendations for this population. While US is usually the first line modality for a focal complaint, mammography, DBT, and DCE MRI also have key roles. The appropriate work up and decision to biopsy should be tailored to the patient’s age, risk stratification, and initial imaging findings.