Breast cancer during pregnancy

Being diagnosed with breast cancer during pregnancy

If you develop breast cancer during pregnancy the treatment you are offered will depend on the type and extent of your breast cancer, the trimester of your pregnancy when the cancer is diagnosed and your individual circumstances. Each trimester of pregnancy represents a number of weeks, the first is from conception to 12 weeks, the second is 13-28 weeks and the third is from 28 weeks to delivery.

Effective treatment for breast cancer can be given during pregnancy without affecting the baby. You cannot pass cancer on to your baby. Your treatment team will include your obstetrician as well as your breast cancer specialist.

Your diagnosis may affect how you feel about your pregnancy and the birth of your baby. Being diagnosed with breast cancer during pregnancy or after the birth may be particularly distressing and bring on many mixed emotions when ordinarily you would expect to feel happy about your pregnancy and the birth of your child.

Coping with treatment may also leave you feeling you are not as involved in your child’s first year of life as you might have wanted.

Continuing your pregnancy

Depending on the trimester, you may need to think about whether or not to continue your pregnancy. The decision to terminate a pregnancy is a very personal one and you should discuss this with your specialist team and obstetrician.

There is no evidence to suggest that a termination will improve the outcome for women diagnosed with breast cancer during pregnancy. However, termination may be discussed if chemotherapy is recommended during the first trimester as this treatment may be harmful to a developing baby.

Whatever you decide, it is important to make the right choice for you.

Treatment during pregnancy and after delivery

The following are treatments that you may be given depending on your trimester and whether you have delivered your baby. If you are near to the end of your pregnancy, your specialist may delay your treatment until after the birth. If you are breastfeeding you will be advised to stop before receiving any treatment.

Surgery

Many women with breast cancer are given a choice between mastectomy (removal of the breast including the nipple area) and breast-conserving surgery (usually referred to as wide local excision or lumpectomy, the removal of the cancer with a margin (border) of normal breast tissue around it).

During pregnancy you are more likely to be offered a mastectomy. This is because after breast-conserving surgery, radiotherapy is needed and this cannot be given while you are pregnant.

If you are diagnosed in your second trimester and will be having chemotherapy after your surgery, you may also be able to have breast-conserving surgery (if appropriate) instead of a mastectomy. This is because radiotherapy will not usually be given until after your chemotherapy has finished, and after your baby has been born.

Immediate breast reconstruction is generally not offered due to the changes in the breast during pregnancy and to avoid a long time under anaesthetic.

Your doctors will also want to check whether breast cancer cells have spread from the breast to the lymph nodes (glands) under the arm (the axilla). This helps them decide which additional treatments you will benefit from after surgery.

To see whether or not any of the lymph nodes under the arm contain cancer cells, your surgeon may wish to do an operation to remove some (a lymph node sample) or all of them (a lymph node clearance). Another way of checking the lymph nodes under the arm is called ‘sentinel node biopsy’. This identifies whether or not the first lymph node (or nodes) is clear of cancer cells. If it is, this usually means the other nodes are clear too, so no more will need to be removed.

However, sentinel node biopsy is not appropriate for everyone and the clinical evidence for the safety of the radioactive material and coloured dye used in this procedure and its effect during pregnancy is very limited. Your surgeon will be able to discuss whether this is a suitable option for you.

Whichever type of surgery you have, it will involve having a general anaesthetic. This is generally considered safe during pregnancy, but there may be a slightly increased risk of miscarriage, especially early on in the pregnancy.

Chemotherapy

Certain combinations of chemotherapy can be given during pregnancy. However, chemotherapy should be avoided during the first trimester as it may cause harm to the unborn baby or cause miscarriage. Generally, chemotherapy during the second and third trimesters is safe.

Radiotherapy

Radiotherapy is not recommended at any stage of pregnancy, as even a very low dose carries a risk to the baby. It can be given after the birth.

Hormone therapy and targeted cancer therapies (for example, trastuzumab, also known as Herceptin) are generally not given during pregnancy.