A breast affected by cancer can still produce milk, but its ability to do so is influenced by the tumor’s characteristics and medical treatments. This is a common concern for individuals who are pregnant, breastfeeding, or considering future lactation while facing a breast cancer diagnosis. Understanding how breast cancer influences milk production and the safety of breastfeeding during treatment involves various factors, from the tumor’s characteristics to the specific medical interventions employed.
Breast Cancer’s Effect on Milk Production
A breast with cancer can still produce milk, though a tumor or its associated changes may alter this process. Lactation depends on the tumor’s size, location, type, and its impact on milk-producing structures. For instance, a tumor near milk ducts can cause compression or obstruction, impeding milk flow. Invasive tumors may disrupt glandular tissue, reducing milk supply in that breast.
Inflammatory breast cancer, a more aggressive form, can cause widespread changes like swelling and redness, interfering with milk production and ejection. While the unaffected breast can compensate by increasing its milk supply, the cancerous breast’s output may decrease or cease entirely.
How Cancer Treatments Affect Lactation
Breast cancer treatments often affect lactation more profoundly than the cancer itself. Chemotherapy can suppress milk production by interfering with rapidly dividing cells, including those involved in milk synthesis. Many chemotherapy drugs are excreted into breast milk, making breastfeeding unsafe due to potential harm to the infant. Radiation therapy, which targets cancerous cells, can damage milk-producing tissue and ducts in the treated breast. This damage often leads to reduced or absent milk production in the irradiated breast, and the milk may have a different consistency.
Surgical interventions, such as lumpectomy or mastectomy, also impact lactation. Lumpectomy, which removes the tumor and a margin of healthy tissue, may disrupt milk ducts and nerve pathways, potentially reducing milk flow.
A mastectomy, involving removal of the entire breast, eliminates the ability to produce milk from that side. Hormonal therapies, commonly used for hormone receptor-positive breast cancers, work by blocking hormones necessary for milk production, interfering with lactation.
Breastfeeding When Diagnosed With Cancer
Individuals diagnosed with breast cancer while pregnant or lactating face complex decisions regarding breastfeeding. The choice to continue nursing from the unaffected breast or to cease lactation depends on the cancer type, stage, and planned treatment regimen. Some may choose to continue nursing from the unaffected breast, especially if the cancer is localized and treatment does not involve systemic therapies that could pass into milk. This approach allows the baby to continue receiving breast milk while the individual undergoes treatment.
Healthcare providers, including oncologists and lactation consultants, offer guidance based on the specific medical situation, ensuring the safety of both the parent and the infant. Balancing the benefits of breastfeeding with the necessity of effective cancer treatment is a primary consideration.
Is Breast Milk Safe for the Baby?
A concern for many is the safety of breast milk for the baby when the parent has breast cancer. Cancer cells themselves do not pass into breast milk. However, breastfeeding safety is compromised when certain cancer treatments are involved.
Many chemotherapy drugs, some targeted therapies, and certain hormonal therapies can be excreted into breast milk. These substances can be harmful or toxic to an infant, potentially causing side effects or interfering with their development. For this reason, healthcare professionals generally advise against breastfeeding during systemic treatments like chemotherapy or specific targeted therapies. Consulting with an oncologist is necessary to determine breastfeeding safety based on the specific treatment plan.