Q & A Breast Cancer During Pregnancy

Q&A: Breast Cancer During Pregnancy

Research shows that chemotherapy given to pregnant breast cancer patients reduces tumor size in mothers and does not appear to harm their children, scientists say.

One of the most recent studies included more than 13 years of data collected from 54 mothers and their children who were exposed to chemotherapy in the womb, says the study’s first author Peter Johnson, M.D., a fellow in M. D. Anderson’s Department of Breast Medical Oncology. Here, Johnson answers questions about the study results.

What were the goals of the study?

We wanted to determine the effectiveness of treating pregnant women with invasive breast cancer with the standard neoadjuvant or adjuvant chemotherapy (chemotherapy given before or after surgery). The treatment is called FAC chemotherapy (5-flurouracil, doxorubicin, and cyclophosphamide). The chemotherapy was given during the second and third trimesters. We waited until after the first trimester when a baby’s major organs had developed.

Additional chemotherapy or radiation therapy, as well as therapies such as Herceptin® and tamoxifen, were to be given after delivery, if needed.

What was the common diagnosis of participants?

The women who consented to the protocol tended to have aggressive (lymph node-positive, hormone-insensitive) tumors. This is why some physicians recommend surgery right away. However, we know that chemotherapy before surgery is beneficial because it can reduce or eliminate the tumor.

What effect did chemotherapy have on patients?

Neoadjuvant chemotherapy made it possible for some women in our study to have a better surgical outcome. In a sizeable portion (63%) of the group, neoadjuvant therapy was effective in down-staging tumors so that less of the breast had to be removed. We believe that this allowed patients to undergo breast conservation surgery, whereas they otherwise may have had to have a complete mastectomy.

Saving the breast is not the primary reason for giving chemotherapy to pregnant women. The sooner chemotherapy can be administered, the more likely we would be able to improve their outcome and survival. The hope was that this could be done without any significant adverse events affecting the children, which seemed to be the case in the study.

What has been the effect on the children?

Most of the babies were delivered at or near term, with only a few babies born a bit younger and needing supplemental oxygen or mechanical ventilation for a day or two. Aside from some breathing difficulties, one baby was born with Down’s syndrome and another with a common kidney abnormality – all of which are keeping within population norms.

Telephone and written surveys completed by parents or guardians showed that, overall, the children did not seem to be seriously affected or impaired. This suggests that the placenta, which supplies food and oxygen to the baby, may have some protective mechanisms that reduce the fetal exposure to these drugs.

Could the children have side effects later in life?

While the children are doing well, there are still potential problems that could crop up as they get older. The long-term effects are not known. We’ve followed some children, from birth to age 15 years, whereas other kids are still very young. It may be years before we can say conclusively that the long-term effects of chemotherapy exposure in utero are small.

But for now, it appears to be true. In a follow-up questionnaire, nearly everybody considered their child to be healthy and developing normally as compared to their siblings and other children.

What is the status of the patients today?

Of the 54 expectant mothers, 70% are still alive and disease-free despite having been originally diagnosed with advanced disease.

What future studies are planned?

Several of our doctors plan to work together with a maternal/fetal specialist at another Houston hospital to collect the placentas and umbilical cords from children born to mothers who received FAC chemotherapy during pregnancy.

We want to measure drug exposure levels in these tissues as well as analyze whether any genetic changes were induced by the chemotherapy and what that may mean for long-lasting health.

In the meantime, M. D. Anderson will continue to treat pregnant breast cancer patients while following their outcomes and those of their children.