Breastfeeding Among Women with Breast Cancer
by Anne Eglash MD, IBCLC, FABM
Caring for a breastfeeding mother with a history of breast cancer or who has a new diagnosis is not well described in the literature, and most lactation consultants don’t have extensive experience with this group of new mothers. The authors for this week’s clinical question article, both surgeons and breastfeeding medicine specialists, provide a thorough and contemporary summary of considerations for this special population of mothers. They review breastfeeding anticipatory guidance for women who have undergone mastectomy, or lumpectomy and/or radiation prior to pregnancy. For women diagnosed with breast cancer during pregnancy and lactation, they discuss the effect of cancer chemotherapy during pregnancy on lactation. They review imaging considerations for breastfeeding women who have suspicious breast masses, and the safety of bone scans and PET scans during lactation. The evidence for timing of mastectomy or lumpectomy during lactation is addressed, as is the safety of dye given for axillary staging (evaluating lymph nodes before surgery).
Survivors of breast cancer can breastfeed successfully, even if they had a unilateral mastectomy or unilateral radiation.
The authors recommend not breastfeeding during chemotherapy for breast cancer, for the safety of both the infant and mother. Mothers desiring to express/discard their milk during chemotherapy so that they can breastfeed between chemo cycles are at higher risk for mastitis because of immune suppression from the chemotherapy. Women who want to continue breastfeeding during breast irradiation are at higher risk for complications in the irradiated breast such as skin breakdown and mastitis. Breastfeeding from the non-affected breast is encouraged.
- Women who have nipple sparing mastectomy may have very small amounts of residual tissue that produces milk and therefore the mother should be encouraged to breastfeed from that side.
- A history of lumpectomy for breast cancer increases the risk of insufficient milk supply from that breast.
- A breast that has undergone radiation for breast cancer is not expected to lactate significantly.
- If a breastfeeding mother has a breast mass that requires a biopsy, a fine (small) needle biopsy should be performed rather than a core needle (large bore) biopsy, because core biopsies are likely to cause significant and persistent milk fistulas.
- Breastfeeding or pumping before a mammogram improves the sensitivity of the mammogram, allowing it to be more effective at identifying lesions.
- Breast MRIs during lactation are very inaccurate due to the presence of milk and should not be relied upon for diagnosis.
- The nuclear isotopes (nuclear contrast) used for bone scans and PET scans, for diagnosis of cancer metastasis, are not excreted into breastmilk.
- Women diagnosed with breast cancer during lactation should be weaned for 6 weeks before having a mastectomy or lumpectomy, to prevent excessive bleeding, milk fistulas, and infection.
- Women who undergo chemotherapy for breast cancer during pregnancy are at high risk for insufficient lactation.
See the Answer
Supporting breastfeeding is a global health priority, yet few clinical guidelines exist to guide surgical oncologists in managing lactation during or after breast cancer treatment.
The literature was reviewed to identify evidence-based strategies for managing lactation during multidisciplinary breast cancer treatment or among breast cancer survivors.
The majority of the evidence is from observational studies, with some higher levels of evidence, including systematic reviews and meta-analyses. Several significant gaps in knowledge remain.
This review serves as a comprehensive resource of evidence-based recommendations for managing lactation in breast cancer survivors and breastfeeding women with a new breast cancer diagnosis.
This is an awesome article. Every lactation consultant, breastfeeding medicine specialist, primary care physician, breast cancer surgeon, and breast cancer oncologist should read it!
Women who have undergone a mastectomy are not expected to make milk from that side due to the complete removal of breast tissue. This is different from a transgender male who has had breast removal, AKA top surgery, where breast tissue removal is not nearly as complete.
A history of lumpectomy for breast cancer increases the risk of insufficient milk production on that side in the future, due to the disturbance of terminal ducts and innervation of the breast from surgery.
A breast that has undergone radiation for breast cancer is significantly scarred, preventing the growth of healthy glandular tissue during pregnancy.
Core biopsies during lactation are not contraindicated, and are necessary to make a correct diagnosis of the breast mass. Milk fistulas from core biopsies are rare.
Breast imaging, whether an ultrasound, mammogram, or MRI are best accomplished after breast emptying by nursing or pumping. Mammograms and breast MRIs are safe during lactation and are useful for diagnosis of a breast lesion or mass.
According to the authors, the optimal timing for a lumpectomy or mastectomy for a breastfeeding mother who is weaning is not clear, since involution changes after weaning vary, and are not necessarily complete until 12-18 months after breastfeeding cessation. They recommend that the weaning process not delay surgery.
The article reviews evidence indicating that chemotherapy during pregnancy may interrupt breast development, impacting breastmilk production postpartum. The earlier chemotherapy is giving during gestation, the likelihood of greater impact on lactation.