Breast cancer during pregnancy

Finding that you have breast cancer while you are pregnant is very distressing. Being well informed about your diagnosis and possible treatments can make it easier to make decisions and cope with what happens.

Breast cancer during pregnancy is very rare, and happens in about 1 in 3,000 pregnancies. Most women are between 32 and 38 years old at diagnosis.

Pregnancy means there may be more issues to consider about treatment. You and your doctors and nurses need to work out the type of treatment you need. Your doctors will also need to understand what you and your family want. This includes thinking about how far along your pregnancy is and what stage of cancer you have.

Most women are able to carry on with their pregnancy. Rarely, some may need to think about whether to continue with the pregnancy. Usually doctors only talk to women about termination of their pregnancy if they need chemotherapy and are less than 14 weeks pregnant. Usually it is possible to delay chemotherapy treatment until after you have reached the 14 weeks stage of pregnancy. Some women feel that they want treatment straight away and decide to have a termination. This is a very difficult, personal decision and one only you can make. And it is one to make after talking to your family, your cancer specialist and obstetrician.

In the past it was thought that breast cancers found during pregnancy behaved differently from other breast cancers and had a worse outlook. But research shows that pregnancy does not affect the outlook.

During pregnancy your breasts change in readiness for breast feeding. The breast tissue becomes more dense. This can make it more difficult to find changes in the breast that are due to cancer. The most common symptom of breast cancer is a lump. If you have a change that doesn’t go away after 2 to 4 weeks tell your doctor or midwife.

Research shows that during pregnancy there is often a delay from the time women start to get breast symptoms to diagnosis. This is partly because breast cancer in pregnancy is so rare. It is also because the cancer can be difficult to diagnose because of the changes in the breast tissue.

You usually start by seeing your GP. Your GP will examine you and if necessary refer you to a specialist breast clinic. At the clinic you will have an ultrasound or a mammogram or both. Mammograms can be more difficult to read because your breasts are denser. If you need a mammogram the radiographer will use shielding to protect the baby from any radiation. You will also need a biopsy to find out for certain if it is a cancer. This may be a core or an excisional biopsy.

If the biopsy shows that you have cancer you may then have other tests to check the size of your cancer. Tests will also check whether the cancer has spread to the lymph nodes under your arm or to other parts of the body. These tests tell the doctor the stage of your cancer. The tests may include a chest X-ray and an ultrasound scan of your liver. You may also have an MRI scan without contrast. If previous tests suggested that your cancer is unlikely to have spread to other parts of our body you may have these tests after you have had the baby. Doctors don’t usually recommend CT scans or bone scans during pregnancy because of the potential risk to the baby from the radiation.

You can find out more about the tests to diagnose breast cancer in the breast cancer section.

Deciding about what treatment to have and what that will mean for you and your developing baby can be very difficult. Doctors advise that your treatment should be as close as possible to what someone who isn’t pregnant would have. And whenever possible the treatment should not be delayed.

The type of treatment you have will depend on

• The type and stage of your breast cancer
• How many weeks pregnant you are (which trimester you are in)
• What you and your family want

Possible treatments include

• Surgery
• Radiotherapy
• Chemotherapy
• Hormone therapy
• Other treatments

Surgery

The main treatment for breast cancer is surgery. Surgery is possible at any time during the pregnancy. You and your baby will be carefully monitored by the anaesthetist while you are having the operation and afterwards. If you are close to your due date your surgeon may suggest you have an induced delivery or a caesarean section. You then then have surgery to remove the cancer a couple of weeks after that. The type of surgery you have depends on

• The size of the cancer in your breast
• The size of your breasts
• Whether the cancer has spread elsewhere in your body
• Your feelings and wishes

You may have your whole breast removed (mastectomy) or just the cancer removed (lumpectomy or wide local excision). The type of surgery you have will also depend on how many weeks pregnant you are. If you have a lumpectomy or wide local excision you are more likely to need radiotherapy after surgery. Radiotherapy is not recommended during the first trimester of pregnancy. There is more information about radiotherapy and pregnancy below.

Your surgeon will also remove some lymph glands from under your arm to see if they contain any cancer cells. Normally, before this type of surgery, doctors do a test called a sentinel node biopsy (SNB). SNB can show whether there are cancer cells in the nearby lymph nodes. If there aren’t, you then don’t have the surgery. But SNB involves having some radiation which could be harmful to the baby. Changes to the lymphatic system during pregnancy may also make sentinel node biopsy less reliable.

There is more information about surgery for breast cancer in the surgery for breast cancer section.

There is no research into reconstructive surgery during pregnancy. Reconstruction is where the surgeon creates a new breast shape with other body tissue or an internal implant. Having this done at the same time as breast cancer surgery makes the operation much longer.  So your doctor is likely to recommend that you wait to have reconstruction surgery until after you have had your baby. There is detailed information about breast reconstruction in our breast cancer section.

Radiotherapy during pregnancy

Radiotherapy uses radiation to destroy cancer cells. Women with breast cancer may need to have radiotherapy after surgery to lower the risk of the cancer coming back. You are most likely to need radiotherapy if you’ve only had the lump removed (lumpectomy or wide local excision). But some women need radiotherapy after mastectomy.

Doctors generally recommend that you don’t have radiotherapy during pregnancy because of the radiation risk to the baby. If you are early in your pregnancy you may need to think about the type of surgery you have so that you can avoid having radiotherapy. If you are in the late part of the second trimester or the third trimester it is likely that your doctor will suggest that you wait to have radiotherapy until after the baby is born. This delay is likely to be short and so will not increase the risk of the cancer coming back.

You can find out more about radiotherapy for breast cancer in the breast cancer section.

Chemotherapy during pregnancy

Chemotherapy is the use of anti cancer (cytotoxic) drugs to kill cancer cells.

If you are in your first trimester you should not have chemotherapy. The chemotherapy can damage the baby or cause a miscarriage. If you need chemotherapy your doctor may delay it until after you are at least 14 weeks pregnant. Most women who are diagnosed during the first trimester have surgery and then will be in their second trimester by the time they need to have chemotherapy. 

The evidence we have so far shows that chemotherapy is safe if women are at least 14 weeks pregnant (in their second and third trimester). There has been a review of the evidence available about children born after exposure to chemotherapy while in their mother’s womb. It suggests that, after 14 weeks, children don’t have any more problems than children not exposed to chemotherapy. The expert panel doing the review suggest that we collect more information over a longer time so that we can understand more about the long term outlook for children.

Chemotherapy is usually a combination of 2 or 3 different drugs. These may include

• Doxorubicin (Adriamycin)
• Cyclophosphamide
• Fluorouracil (5FU)
• Epirubicin
• Docetaxel

You will stop having chemotherapy at least 3 to 4 weeks before delivery. This is because chemotherapy increases the risk of getting an infection during delivery. It also increases the risk of bleeding, because it lowers your blood counts. Stopping chemotherapy for 3 weeks allows your blood counts time to recover. This lowers the risk of bleeding and infection during the birth of the baby.

Hormone treatment during pregnancy

Hormone treatment, including tamoxifen, is a common treatment after surgery for breast cancer. Doctors do not recommend hormone treatment during pregnancy because of the effect it can have on the developing baby. If you have a hormone sensitive cancer you may start hormone treatment after you have given birth.

You can read more about hormone treatments in the breast cancer section.

Other treatments

Doctors don’t recommend using biological treatments for breast cancer such as Herceptin during pregnancy.

Women having treatment for breast cancer usually need other supportive treatments such as anti sickness medicines. We know from research that anti sickness drugs, such as ondansetron do not affect a developing baby.

When you have your baby will depend on the treatment you need and your expected due date. To time the delivery with your treatment, your obstetrician will either induce the birth so that you have a vaginal delivery. Or they may suggest a caesarean section.

You will be as near to your due date as possible. If you are having chemotherapy it is usual to wait at least 3 weeks after the last dose. If your chemotherapy is to carry on after the baby is born, it is best to have a vaginal delivery because you need less time to recover before restarting chemotherapy.

After the birth a specialist children’s doctor (a paediatrician) will examine the baby. Many women worry about the effect of the breast cancer on the baby. Breast cancer has never been known to spread to the baby. A pathologist will examine the placenta because, although very rare, it is possible for cancer cells to spread there.

If you need further treatment with chemotherapy or hormone treatment after the birth, you won’t be able to breast feed the baby as the drugs pass into the milk.

A diagnosis of breast cancer during pregnancy is particularly distressing. This is a time when you would normally be happy and looking forward to the future. You are likely to feel a range of emotions including anger, worry, fear, sadness or depression. After you have the baby you may need to continue treatment. This may make caring for your new baby more difficult, especially if you have other children. It is important to get practical and emotional support from the people around you. It may help to plan ahead by thinking about what you will need and finding out what other people can offer. 

A team of specialists will look after you and be there to support you. Try to make use of the support they can offer to you and your family. Some people find that sharing their feelings can help them sort out how they feel and what they want. You may want to talk to

• The people close to you
• Professional counsellors
• Organisations which offer support – see our breast cancer organisations page
• People who have been through a similar experience – from a support group or Cancer Chat (Cancer Research UK’s patient forum)