Pregnancy and Breast Cancer

Breast cancer remains one the most common cancers encountered in the pregnant population, with infiltrating ductal adenocarcinoma carrying the highest incidence. Pregnancy-associated breast cancer encompasses cancer diagnosed during pregnancy itself, during the first postpartum year or anytime during lactation. Diagnosis is guided with mammography, magnetic resonance imaging (MRI) without gadolinium, and chest X-ray. Diagnosis is confirmed with breast and axillary node biopsy. Termination of pregnancy should be discussed and offered with patients, although termination has not been shown to improve maternal outcomes. Treatment options, including mastectomy and chemotherapy, should not be withheld or delayed due to the gravid state. There is a low level of neonatal complications in fetuses exposed to chemotherapeutic agents. While the risk of vertical transmission to the fetus is unknown, placental metastasis is rarely encountered. Maternal prognosis appears to be reassuring if the cancer is diagnosed and treated appropriately, with survival not being negatively affected in the setting of pregnancy-associated breast cancer.