Chemotherapy is usually given with both positive-and negative-node breast cancers. In premenopausal women, survival rates with this approach are improved, even if lymph nodes are cancer free. For node-positive disease, multiagent chemotherapy is begun if delivery is not anticipated within several weeks. Cyclophosphamide, doxorubicin, and cisplatin are currently used (Euhus, 2016). If an anthracycline-based agent such as doxorubicin is used, pretherapy maternal echocardiography is performed because of associated cardiotoxicity (Brewer, 2011). Good maternal and perinatal results have been reported (Berry, 1999; Hahn, 2006).
Immunotherapy for breast cancers is now commonplace.
T rastuzumab (Herceptin) is a monoclonal antibody to the HER2/neu receptor, which is found in approximately a third of invasive breast cancers (Hudis, 2007). The drug is not recommended in pregnancy. This is because HER21 neu is strongly expressed in fetal renal epithelium, and trastuzumab has been linked with miscarriage, fetal renal failure and related oligohydramnios, and preterm birth (Amant, 2010; Azim, 2010).
he efects of pregnancy on the course of breast cancer and its prognosis are complex. Breast cancer is more aggressive in younger women, but whether it is more aggressive during pregnancy in these same women is debatable (Azim, 2014). Clinically, most studies indicate little diference in overall survival rates with pregnancy-associated breast cancer compared with similarly aged and staged nonpregnant women (Beadle, 2009).
Other reports note worse overall survival rates with pregnancy associated breast cancer (Rodriguez, 2008). hese investigators do conclude, however, that later disease stages are more preva lent in pregnant women.
Indeed, breast cancer is usually found at a more advanced stage in pregnant women, and thus overall prognosis is dimin ished (Andersson, 2015). The aggregate of studies published after 1990 indicate that up to 60 percent of pregnant women have concomitant axillary node involvement at diagnosis. And although, stage for stage, the 5-year survival rate is compara ble in pregnant and nonpregnant women, the more advanced stages that are typical of pregnant women worsen their progno sis (Kuo, 2017; Zemlickis, 1992).
After breast cancer treatment, chemotherapy will render some women infertile, and options for childbearing are limited (Kim, 2011). For those who become pregnant, long-term maternal survival rates are not adversely afected (Averette, 1999; Velentgas, 1999). One metaanalysis of 10 studies found that for women with early breast cancer, pregnancy that occurs 10 months after diagnosis may, in fact, confer a survival benefit (Valachis, 2010). Data do not indicate that breastfeeding adversely the course.
In women successfully treated for breast cancer, recurrence is a concern. Because recurrences are more common soon after treatment, it seems reasonable to delay conception for 2 to 3 years. Hormonal contraceptive methods are contraindicated, and a copper-containing intrauterine device is an excellent long-acting reversible method for many. That said, women who conceive do not appear to have diminished survival rates (Ives, 2006). Notably, women treated with tamoxifen are at risk for several months after its discontinuation to have a newborn with congenital anomalies. This drug has an extremely long half-life, and thus delaying conception is recommended for at least 2 months after tamoxifen completion (Braems, 2011).