You may have side effects during treatment for breast cancer and after treatment ends. Usually, these get better slowly and then stop. Sometimes side effects do not go away, or they can develop months or years after treatment. These are called late effects.

What are late effects?

Most women have side effects during treatment for breast cancer and for a few weeks after treatment ends. Usually, these side effects get better slowly and then stop. But sometimes side effects do not go away. Or they can develop months or years after treatment.

There are two commonly used terms for these side effects:

  • Long-term effects
    Long-term effects begin during, or shortly after, treatment. They last for more than 6 months after treatment has finished. They may go away on their own, with symptoms getting better over 1 or 2 years after treatment. Or they may be permanent. 
  • Late effects
    Late effects are a delayed reaction to treatment. They do not appear during treatment, but can happen months or even years later.

In this information, we use the term late effects to describe both long-term and late effects.

Coping with late effects

There are many things that can be done to manage or treat late effects. It is important that you do not feel you have to cope with them without getting help.

Late effects may be minor and not affect your daily life much. Or, they may be more difficult to live with and affect your daily life more. There are usually a lot of things that can help you cope with them to live life as well as you can. Some late effects improve over time and may eventually go away on their own.

If side effects do not go away after treatment, or if you develop late effects, always let your cancer doctor or specialist nurse know. You can contact your specialist nurse even if you no longer have follow-up appointments with a doctor. You can also contact your GP.

The breast care team can assess your symptoms. They will explain whether they could be caused by treatment and how to manage them.

Some late effects may be similar to the symptoms you had when you were first diagnosed. This can be scary, and you may worry the cancer has come back.

Sometimes symptoms are caused by other conditions not related to the cancer or its treatment. Your doctor may arrange tests to find out more about the cause of your symptoms. If you are unable to work because of late effects, you may be entitled to some benefits.

Breast and arm changes

Surgery and radiotherapy to the breast can cause a number of changes. These can include:

Tiredness and fatigue

Tiredness is probably the most common side effect of breast cancer treatment. It is common for tiredness to last for months after treatment is over. For some people, it may last for 1 or 2 years.

Some people feel very tired and exhausted most, or all of the time. This is known as fatigue.

We have more information about managing tiredness.

Effects on the heart

Some treatments for breast cancer may increase the risk of developing heart problems, usually many years later.

These include, chemotherapy drugs, for example, doxorubicin and epirubicin, radiotherapy to the left breast, hormonal therapies and a targeted therapy, called Trastuzumab (Herceptin).

We have more information about how cancer treatments can affect your heart. These include anthracyclines and radiotherapy.

Most people will never experience any effects on the heart. But it may help to understand more about how you can take care of your heart.

Risk factors

The most important risk factor for developing heart problems is pre-existing heart disease, including high blood pressure. Women at risk are carefully monitored before and after treatment to find out if their treatment needs to be changed.

Having an early menopause because of your treatment may increase the risk of heart problems. This is because oestrogen and progesterone help protect the heart.

We have more information about the symptoms of heart problems and how to reduce your risk of developing heart problems. If you already have problems, small changes can help to reduce your risk of further problems.

The British Heart Foundation has lots of information and advice about keeping your heart healthy.

Effects on the lungs

Radiotherapy can cause problems with breathlessness months or years after treatment. However, this is a rare side effect because radiotherapy is carefully planned and ways of giving it have improved.

We have more information about late effects on the lungs.

Effects on the bones and joints

Bone thinning

After the menopause, all women have an increased risk of bone thinning (osteoporosis). But after breast cancer treatment, some women are at a greater risk. This is because some treatments can reduce the amount of oestrogen in the body. Oestrogen helps to keep bones healthy and strong.

Treatments for breast cancer that can increase the risk of bone thinning are:

We have more information about bone health.

Pain in the joints and muscles (arthralgia)

Women taking aromatase inhibitors may have joint pain and sometimes muscle pain. Joint pain is also a common symptom of the menopause.

We have more information about managing joint and muscle pain.

Weight gain

After breast cancer treatment some women find that they have gained weight. This can happen if:

  • chemotherapy or another treatment has caused an early menopause
  • you are taking steroids, which are often given with chemotherapy
  • you are having hormonal therapies
  • you are less active during treatment and eat a less healthy diet.

Losing weight can be difficult. Even keeping to a healthy weight is sometimes hard. But there are lots of benefits. It reduces the risk of getting heart problems and other illnesses such as diabetes. There is evidence that keeping to a healthy weight after the menopause helps reduce the risk of breast cancer coming back.

We have more information about managing weight gain after cancer treatment.

Peripheral neuropathy

Peripheral neuropathy (also called neuropathy) is damage to nerves that carry messages between the brain, the spinal cord and the rest of the body. Nerve damage can cause symptoms in the hands and feet, such as:

  • pins and needles
  • numbness
  • pain.

For a few people, this may lead to problems with balance and walking.

Treatment with the chemotherapy drugs docetaxel or paclitaxel is the most common cause of peripheral neuropathy in women who have had breast cancer. Surgery and radiotherapy to the breast may also cause nerve damage.

We have more information about peripheral neuropathy.

Diabetes

Some hormonal therapies used to treat breast cancer can slightly increase your risk of developing diabetes. Diabetes is a condition where the amount of glucose in the blood is too high. Glucose is a type of sugar that our bodies use for energy.

Usually, the benefits of hormonal therapies outweigh the small risk of diabetes. Your doctor or specialist nurse can talk to you about this.

Most women will not get diabetes because of their cancer treatment. But it may help to know the symptoms of diabetes so you can get them checked, if they develop.

Symptoms of diabetes

Diabetes can cause the following symptoms:

  • passing a lot of urine (peeing), especially at night
  • feeling very thirsty
  • feeling very tired
  • losing weight for no obvious reason
  • itching in the genital area or getting thrush a lot
  • cuts and wounds that take a long time to heal
  • blurred vision.

These symptoms can be caused by many other conditions. But you should always talk to your GP if you have any of them.

Effects on your sex life and fertility

Sex life

Breast cancer and its treatment can affect your sex life and your body image. Body image is how you think and feel about your body and how you think others value you. You may lose interest in sex, feel unattractive or worry that you will never be able to be sexually active. For some people, these problems continue long after treatment is over.

We have more information about cancer and your sex life.

Fertility

Hormone therapy and chemotherapy can affect your ability to have children (fertility). If you have had treatment and are having difficulty getting pregnant, ask you doctor to refer you to a fertility specialist.

We have more information about how cancer treatment can affect fertility.

Menopause and menopausal symptoms

Some breast cancer treatments can affect the way the ovaries work. This can cause an early menopause for some women, which may be temporary or permanent. It can also cause side effects similar to menopausal symptoms. Sometimes these effects do not last long.

We have more information about managing menopausal symptoms.

Concentration and memory problems

After treatment for breast cancer, some women have difficulties concentrating and remembering things. Doctors call this cognitive impairment.

It is also sometimes called chemo brain or chemo fog. But these changes can also happen with other cancer treatments, such as hormonal therapy.

An early menopause may result in similar symptoms, or make them worse.

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