Breast Imaging During Lactation
by Anne Eglash MD, IBCLC, FABM
The American College of Radiology recently published their Appropriateness Criteria for Breast Imaging of Pregnant and Lactating Women. During pregnancy and lactation, the breasts become denser, making the breasts harder to image when looking for small lesions. The changes in the breast anatomy and physiology indicate the need for special imaging recommendations. The group recommends routine breast cancer screening for pregnant and breastfeeding women, according to standard guidelines.
Breastfeeding mothers do not need to wean before having routine mammograms done. This is important since many women in their 40’s give birth and lactate, when breast cancer screening is routinely recommended.
- An isolated episode of bloody nipple discharge during pregnancy or early lactation without a palpable breast mass is never normal and should always be evaluated with imaging.
- Benign breast masses, such as pre-existing fibroadenomas, may grow during pregnancy and lactation.
- Breastfeeding or pumping before a mammogram might improve diagnostic accuracy.
- Adding 3-D mammography, also known as digital breast tomosynthesis, may improve mammogram accuracy during lactation.
- Breast MRI with contrast is reasonable for a breastfeeding woman at high risk for breast cancer who is due for her screening breast imaging.
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Breast imaging during pregnancy and lactation is challenging due to unique physiologic and structural breast changes that increase the difficulty of clinical and radiological evaluation. Pregnancy-associated breast cancer (PABC) is increasing as more women delay child bearing into the fourth decade of life, and imaging of clinical symptoms should not be delayed. PABC may present as a palpable lump, nipple discharge, diffuse breast enlargement, focal pain, or milk rejection. Breast imaging during lactation is very similar to breast imaging in women who are not breast feeding. However, breast imaging during pregnancy is modified to balance both maternal and fetal well-being; and there is a limited role for advanced breast imaging techniques in pregnant women.
Mammography is safe during pregnancy and breast cancer screening should be tailored to patient age and breast cancer risk. Diagnostic breast imaging during pregnancy should be obtained to evaluate clinical symptoms and for loco-regional staging of newly diagnosed PABC.
This is an important set of recommendations. I believe that breastfeeding women have been at risk for a delay in routine screening for breast cancer, because they have been told in the past to start their mammograms approximately 3 months after weaning, even if they are due for breast cancer screening based on age and family history. Even though pregnancy and breastfeeding reduce the long term risk of breast cancer, there is a higher short term risk of breast cancer during pregnancy, called Pregnancy-Associated Breast Cancer (PABC). This document emphasizes the need to not delay breast cancer screening or imaging for breast masses due to concerns about risks of radiation, although they recommend modifications specific to pregnancy and lactation.
For women who experience an isolated episode of bloody nipple discharge during pregnancy or early lactation, no imaging is necessary if there is not an associated mass and the bloody discharge does not recur. The authors acknowledge the validity of the ‘Rusty Pipe Syndrome’, and state that 20% of pregnant women may experience this, due to the increased number of small blood vessels in the breast during pregnancy.