Breast cancer and pregnancy | What you need to know

Posted on June 8th, 2015

Professor Justus Apffelstaedt, Head of the Breast Clinic at Tygerberg Hospital answers some frequently asked questions about breast cancer and pregnancy.

Breast cancer and pregnancy

Breast cancer occurs in about one in every 3 000 pregnancies, most often in women between the ages of 32 and 38. More and more women postpone pregnancies to an age where breast cancer becomes more common. Therefore, we are seeing more and more breast cancer, which is complicated by pregnancy.

Can a pregnant woman have a mammogram?

Regular screening mammography in women without any symptoms, isn’t done during pregnancy. However, mammography during pregnancy may be considered for women with signs or symptoms of a possible breast problem. It is preferable, however, to use other diagnostic modalities that do not involve radiation or administration of contrast agents.

Can a mammogram harm a foetus?

Small studies have found that mammography poses little to no harm to the foetus during pregnancy if a lead shield is placed on the belly to block any possible radiation scatter. However, the accuracy of mammography is limited during pregnancy. In three different studies, the percentage of breast cancers in pregnant women that were detected via mammography, was between 62% and 78%. This is significantly lower than the average 85% detection rate in non-pregnant women.

Can breast cancer spread to your baby when you’re pregnant?

No. A barrier between the mother’s and the baby’s body blocks any cancer cells from entering the baby.

Do women respond to cancer treatment as well as women who are not pregnant?

Research shows that women diagnosed during pregnancy respond just as well to treatment as women that are not pregnant.

What treatment is given to pregnant women with breast cancer?

In the first trimester of pregnancy, serious consideration must be given to perform a therapeutic abortion. This is obviously a very difficult decision and must be made in consultation with the obstetric and oncologic teams. If the decision is taken to proceed with the pregnancy, a mastectomy is usually well tolerated during the second trimester. Findings from several recent studies suggest that chemotherapy may be administered with moderate safety if the pregnancy has passed the first three months, which is a critical period for foetal organ formation. It is suggested that patients who are in the first three months of pregnancy may wait until the critical period of foetal organ formation is over before receiving chemotherapy. Hormonal therapy of breast cancer is impossible at any time during pregnancy. No data are available on the safety of biologicals in pregnancy. Pregnant women cannot have radiation therapy as it will cause serious damage to the foetus in a large number of cases.

When is suppression of lactation necessary?

Suppression of lactation does not improve prognosis. If surgery is planned, however, lactation should be suppressed to decrease the size and vascularity of the breasts. If chemotherapy is planned, lactation should also be suppressed, as many chemotherapeutic agents such as chemotherapeutic agents may occur in high levels in breast milk, and would affect the baby. In general, women having chemotherapy should not breastfeed.

Does pregnancy have an impact on the risk of recurrence of breast cancer?

Studies have shown that women who were diagnosed with breast cancer during pregnancy did as well in the long term as women with the same type and stage of cancer that were not pregnant when they were diagnosed. There is no apparent long-term increased risk of cancer recurrence or death in women who became pregnant after a breast cancer diagnosis.

Living And Loving Staff

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