Breast Cancer While Pregnant: The Safest Treatment for Mom and Baby

It was at her first consultation for a diagnosis of breast cancer that a 34-year-old patient learned she was pregnant.

The woman and her husband had been trying to have a second child, but didn’t know they had conceived until she went to her consultation at the Stefanie Spielman Comprehensive Breast Center at the James Cancer Hospital at Ohio State University and took a pregnancy test, part of the standard workup for patients considering surgery.

Her treatment plans were abruptly stopped, evaluated and reconfigured with the goal of administering therapy while protecting the pregnancy.

The case inspired a nurse who worked with the patient — Caitlyn Hull, RN, M.S., WHNP-BC — to consider what accommodations might be needed for patients who experience breast cancer and pregnancy at the same time, and what her colleagues should know about how to treat them. That research led to a presentation she has given several times at her institution; on May 5, she summarized the information in a poster and talk at the 42^nd Annual Congress of the Oncology Nursing Society.

Hull defined “pregnancy associated breast cancer” as disease occurring during or within the 12 months following pregnancy. Among all breast cancers in women under the age of 40, 2 to 3 percent occur simultaneously with either pregnancy or lactation. However, because breast cancer risk increases with age and many women are postponing pregnancy until later in life, the incidence of pregnancy associated breast cancer may increase, Hull said.

The cancer outcomes for women in this population are no different than for patients who are not pregnant while fighting breast cancer, but these expectant mothers experience higher rates of C-section and induced birth.

The National Comprehensive Cancer Network has a clinical treatment guideline for pregnancy associated breast cancer, Hull said. The guideline suggests that pregnant patients with breast cancer should get the same treatments as their counterparts who aren’t pregnant, appropriate to the biology of the tumor and the stage of the disease, but on a tailored schedule that balances the woman’s treatment needs against the safety of the fetus.

For instance, surgery is safest when done in the second trimester. Lumpectomy is preferred over mastectomy, and lymph node evaluation should be done with Technitium-99m sulfur colloid, which is safe for the fetus, but without the use of blue dye for lymphatic mapping.

Chemotherapy, too, should be started after the first trimester, since by this time the majority of the fetus’s organ development has occurred. Chemotherapy should be stopped by the time the patient is 35 weeks pregnant, to avoid increased risk for pre-term delivery and neutropenia, a low white blood cell count that can lead to infection, in both the mother and the infant. Finally, there should be two to three weeks between the last dose of chemotherapy and childbirth, to minimize myelosuppression, or decreased bone marrow activity, for mother and child. New mothers who are undergoing chemotherapy treatment should not breastfeed, Hull said.

The targeted drug Herceptin (trastuzumab), indicated for women with HER2-positive breast cancer, should be avoided during pregnancy because there isn’t enough evidence yet that it’s safe, Hull said.

The patient who inspired Hull’s study had surgery at 13 weeks, recovered and then was given Adriamycin (doxorubicin) chemotherapy until she was 35 weeks pregnant. Closer to the patient’s due date, doctors induced labor.

After recovering from her baby’s birth, the patient, whose cancer was HER2-positive, was administered Herceptin and the chemotherapy Taxol (paclitaxel).

While some pregnant patients complete four rounds of Adriamycin before giving birth, others may only finish two rounds during pregnancy and then take two after, Hull said.

She acknowledged that Adriamycin is a chemotherapy known for harsh side effects. However, there are medications expectant mothers can take to manage these side effects, and developing fetuses do well with the regimen, Hull said.

The difficulty in agreeing to such regimens is “more the psychosocial piece,” Hull said. “You have to trust your doctor that this is safe, and that you are taking care of yourself and your newborn.”

Hull cautioned that it’s easy to miss breast cancer in a pregnant woman by attributing a lump or a red breast to her pregnancy. In fact, she said, pregnant women who develop breast cancer tend to be diagnosed three to seven months later than women who aren’t pregnant.

“If you have a friend or a colleague who’s pregnant and says she has a breast problem that isn’t getting better, make sure she gets checked out,” Hull said.

Women who have breast cancer while pregnant should be offered the option of pregnancy termination, especially when the cancer is at a higher stage or aggressive, Hull said. However, she pointed out that studies do not show any maternal survival benefit due to pregnancy termination during breast cancer.

It’s also crucial that these patients get help with psychosocial issues, since they may be experiencing the loss of their dream of motherhood, an inability to breastfeed or bond with their baby due to treatment side effects, loss of fertility or risk of menopause, difficulties in balancing their own care with their infant’s, concerns about body image or sexuality, and depression or anxiety, Hull said.

She recommended a multidisciplinary approach to the care of these women that can include medical, surgical, radiation and psychosocial oncology; reconstructive surgery; maternal-fetal medicine; social work; clinical genetics; and guidance from a dietician.