Treatments and possible consequences

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When breast cancer is diagnosed, the aim of treatment is usually to remove all of the tumor. But this is no longer possible if it has spread to other parts of the body. Then the aim of treatment is to keep your overall health and quality of life as good as possible for as long as possible.

The goal of treatment for metastatic breast cancer is to stop or slow down the growth of the tumor. It is also possible to reduce the symptoms and possible side effects of treatment and to treat associated medical conditions. Cancer-related pain can be treated with well-managed pain relief therapy. If treatment is carefully planned and tailored to a person's specific situation, and if their overall health is good, it is often possible to keep the disease under control for years, even if they have metastatic tumors, and have a good quality of life despite the symptoms.

Side effects and mental health

Cancer treatment can be difficult to go through. It often has severe side effects and sometimes leads to complications. The side effects vary depending on the kind of treatment, but they can often be effectively treated themselves. The treatment of side effects is part of what is known as supportive care. If the treatment is too distressing, though, there may be good reasons for deciding not to have (further) treatment.

One common side effect is . The word '' describes paralyzing physical and mental exhaustion and tiredness that can be accompanied by increased irritability. People may be affected by the whole time they are having treatment, and sometimes even longer. It is most likely caused by physical and psychological reactions to the disease and the treatment. Fatigue can be very distressing and make people feel (more) down. Even small tasks may become impossible or very difficult to perform. It is important to talk to your doctor and find your own personal way of dealing with .

Any life-threatening disease that requires repeated courses of physically draining treatment will inevitably end up affecting your mental health too. Almost everyone in this situation will feel down from time to time. If these feelings last for a longer period of time, depression may develop. It is then important to get treatment because is in itself a serious disease.

Grief, , fear, anger and aggression are all normal feelings. They can be very difficult to cope with. On top of this, your everyday life and social life will be affected. For instance, you might no longer be able to work or take part in social activities the way you used to. Friendships and relationships may change too.

Treatment options

In Germany, metastatic breast cancer can be treated in certified breast cancer centers or tumor centers as well as practices specialized in oncology. There, specialists from different disciplines work together to treat the various effects that both the disease and the treatment have on your body and mind. Metastatic breast cancer can also be treated in hospitals or practices without this certification.

If breast cancer has spread to other parts of the body, the entire body is usually treated with medication (systemic therapy) to limit tumor growth. Either hormone treatment or chemotherapy can be used for this purpose. Certain types of breast cancer can also be treated with targeted therapies, for example antibody therapy.

In most cases, different treatments are used one after the other. Some treatments can also be combined. If tumor cells stop responding to a certain drug after a while, another drug or treatment approach can be used to limit tumor growth. This step-by-step approach is known as sequential therapy. Some metastatic tumors can also be treated with radiation, and it might be possible to surgically remove certain tumors.

Because the type of breast cancer and the way it progresses varies so much from woman to woman, there is no such thing as “the” best treatment. It is important to find suitable, individually tailored treatments for each phase of the disease and to coordinate the different treatments in the best possible way. This is not always easy, and requires good cooperation with your doctors as well as within the treatment team.

There is usually no immediate time pressure when deciding whether or not to have (further) treatment because starting treatment a bit later hardly influences the outcome of treatment. So you can take your time to consider the advantages and disadvantages of the suggested options and think them over for a few days or weeks. If necessary, you can get additional information or second opinions too. You also always have the right to refuse treatment or stop your treatment – regardless of whether it was offered or started at a doctor's practice, in a hospital, or as part of a study.

Hormone therapy

In women with "hormone-receptor-positive" breast cancer, the growth of the tumor is usually stimulated by the estrogen and progesterone. The growth of hormone-sensitive tumors can be limited by reducing the production of in the ovaries or interfering with hormone action (hormone therapy). To do this, women take drugs known as anti-estrogens (e.g. tamoxifen or fulvestrant) before menopause or drugs called aromatase inhibitors after menopause. Medications known as GnRH analogues are sometimes used as well, particularly in younger women. When taken regularly, these drugs prevent the ovaries from producing sex .

Side effects and complications

Anti-estrogens can increase the risk of thrombosis and cause changes in the lining of the womb. Aromatase inhibitors can cause muscle and joint problems, among other things. They can also lower bone density, which increases the risk of bone fractures.

Younger women who are having hormone therapy stop getting their periods. They cannot get pregnant during treatment. The treatment often leads to problems that can also arise during menopause, such as hot flashes, sleep problems, dry skin and dry mucous membranes.


Chemotherapy is treatment with drugs that inhibit cell division. These drugs are called cytostatics. Cytostatics are usually given as infusions (as a drip), but are also sometimes taken in the form of tablets. There are many different cytostatics. They can either be combined with each other or used on their own (monotherapy). Because they are carried by the bloodstream, cytostatics affect the whole body and can even reach metastatic tumors that might not have been discovered yet.

The aim of chemotherapy is to slow down or stop tumor growth, or to make tumors shrink as much as possible. There are different types of chemotherapy for metastatic breast cancer. They are usually given one after the other. When deciding which drugs to use, the doctor and patient take into account the possible side effects and how distressing those side effects are considered to be. Other medical conditions may also play a role when choosing the treatment.

Chemotherapy usually consists of various cycles or courses of treatment. This means that you take the medication for several days, and then stop taking it for a while so your body can recover. Nowadays, chemotherapy is usually given in an outpatient setting. But you might still need to stay in hospital if the treatment is intensive and certain body functions have to be closely monitored.

Side effects and complications

Chemotherapy damages healthy body cells too, particularly rapidly dividing cells such as cells in hair and the mucous membranes, and blood cells. The resulting side effects include hair loss, mouth sores, nausea and indigestion. Signs of blood cell damage may include pale skin (anemia), susceptibility to infections, shortness of breath and exhaustion (). People may also bleed more easily.

The severity of side effects varies from woman to woman and also depends on the drug, the dose, and how the drug is used. Because healthy cells can renew themselves, most of the side effects of chemotherapy are only temporary. In other words, they only occur during chemotherapy or as long as its effects last. There are effective treatments for some of the side effects. For example, anti-nausea medication can be taken before (for prevention) and during chemotherapy. Infections that arise during chemotherapy can be treated with .

Many cytostatics affect ovary function. Women who have not yet entered menopause then stop getting their periods. The resulting sudden drop in can lead to hot flashes, sleep problems and dry skin. Whether or not a woman's menstrual cycle returns to normal after chemotherapy will depend on various factors, including her age.

Targeted therapies

In recent years we have seen the approval of a number of drugs specifically for the treatment of types of cancer with certain tumor cell characteristics. For instance, cancer cells containing the growth factor receptor "HER2" can be treated using antibodies such as pertuzumab and trastuzumab. The drug lapatinib is also an option here.

These medications aim to block growth-stimulating signals in the cancer cells, thereby inhibiting tumor growth and shrinking metastatic tumors. They are typically used in combination with chemotherapy. Trastuzumab can also be used in combination with the drug emtansine. Emtansine is believed to specifically kill cancer cells.

Another example of an antibody used in breast cancer treatment is bevacizumab. It is used in HER2-negative tumors to cut off the cancer cells' blood supply. Like other drugs, bevacizumab is given as an infusion and used in combination with a chemotherapy drug. In November 2011, the U.S. regulatory authority FDA withdrew the approval of bevacizumab for the treatment of metastatic breast cancer. This is because the FDA considers bevacizumab to be more harmful than beneficial in advanced breast cancer.

Side effects and complications

Treatment with the antibody trastuzumab can damage the heart. When combined with emtansine it can cause side effects such as blood clotting problems, exhaustion (), nausea, vomiting and diarrhea. The possible side effects of pertuzumab include anemia, a decrease in the number of white blood cells, and diarrhea. Bevacizumab can cause high blood pressure and bleeding in the digestive tract, and lead to an increased amount of protein being excreted in the urine. In May 2013 the manufacturer issued a warning concerning further possible risks associated with bevacizumab. There had been reports of a rare but life-threatening skin called necrotizing fasciitis in various patients.

The possible side effects of lapatinib include diarrhea, skin rashes and liver damage.

Surgical treatment

If possible, breast cancer tumors are surgically removed in order to prevent them from growing and stop cancer cells from spreading to other parts of the body. Sometimes the tumor can be removed without having to remove the breast (breast-conserving surgery). If the breast is removed (mastectomy), it is often possible to reconstruct it.

In metastatic breast cancer, the tumor has already spread to other parts of the body. Non-surgical treatments are then the main options for keeping tumor growth under control.

Side effects and complications

If lymph nodes are removed from the breast area and nearby armpit, may occur. The arm on that side of the body then becomes swollen because lymph fluid builds up in it.

Just like after any operation, the area in question might hurt. And the surgery usually leaves a visible scar. The wound healing process might take longer due to other cancer-related treatments. But wound healing problems are rare. The surgery may also reduce the sensitivity of your skin and make it more difficult to move your shoulder.

Losing one or both breasts is a major blow for a lot of women. The breast is a symbol of femininity, sexual attractiveness and motherliness. Women may fear that losing a breast will make them less attractive, that they won't be able to enjoy sexuality anymore, or that their partner might even leave them. Because the removal of a breast is associated with these fears and because it might have side effects, it can be a good idea to get a second opinion or further information before deciding whether or not to have the surgery. There is usually enough time to do so. Breast reconstruction might also be an option. Professional support such as counseling for cancer patients can be helpful here.


In radiotherapy – also called radiation therapy – the tumor tissue is exposed to high-energy radiation. The aim is to damage cancer cells so much that they die. In external radiotherapy, radiation is aimed at the cancer from outside the body, through the skin (percutaneously). In internal radiotherapy, radioactive material is placed directly inside the tumor or very close to it.

Radiotherapy is usually the treatment of choice if it is no longer possible to remove the tumor or reduce its size surgically. Radiotherapy can also be used to treat metastatic tumors.

After surgery, radiotherapy aims to remove any cancer cells that might still be there, lowering the risk of the tumor coming back.

Side effects and complications

One of the most common side effects of radiotherapy is tiredness. Radiation can also damage healthy tissue, particularly the skin in the exposed area. The skin there may become sensitive or red, for example. But healthy cells can recover more easily than tumor cells, so these problems usually only occur during and for some time after therapy. Radiotherapy in the lymph node area increases the risk of .

Treating individual metastatic tumors

In metastatic breast cancer, the tumor has spread to other parts of the body, for example bones, skin, the lungs, the liver and the brain. How these metastatic tumors are treated will depend on where they are.

Metastases in bones

If there are metastases in bones, the cancer cells interfere with the process of building up and breaking down bone tissue. This affects the stability of the bones, causing them to break more easily.

Bone metastases can be treated using radiotherapy. Radiation of bone metastases aims to relieve pain and to strengthen bone stability in order to prevent fractures. Bone metastases can also be operated on to ease pain and to stabilize the bones.

Medication can inhibit bone loss. Although drugs called bisphosphonates cannot completely prevent bone damage due to metastases, they can at least slow down bone loss enough to reduce the likelihood of bone fractures. Severe side effects such as the death of jaw bone tissue (osteonecrosis of the jaw) are rare.

Another drug that inhibits bone loss is called denosumab. Denosumab can lead to urinary tract infections, respiratory infections and cataracts. It can also increase the risk of jaw bone tissue necrosis and problems with metabolism.

Metastases in internal organs and the skin

Metastases in skin or internal organs – for instance, in the lungs or the liver – can be specifically treated if

  • there are no other metastases in the body,
  • metastases are only found in one lung or in one lobe of the liver (not in both),
  • the tumor has not grown back in the same place (recurrence),
  • there is no second tumor, and
  • there was more than one year between the first treatment and the occurrence of the metastases.

Surgery is an option for lung metastases if there is only one single metastatic tumor or if the metastases are found in only one lung. The operation is usually followed by treatment with medication.

Metastases that only occur in one lobe of the liver can also be surgically removed. Radiofrequency ablation (RFA) is an alternative to surgery. In this procedure, a probe is used to increase the temperature of the metastatic tissue and damage it so much that it can no longer grow. Both surgery and RFA are usually followed by treatment with medication.

Metastases sometimes arise in a part of the lungs called the pulmonary pleura too. This can lead to the build-up of fluid in the pleural cavity (the narrow space between the lungs and the ribs). The medical term for this is pleural effusion. Built-up fluid can cause breathing difficulties and pain. Surgery can be done or medication can be taken to seal up this space and prevent fluid from building up there.

Clearly outlined metastases on the skin or in muscles can be surgically removed or treated with radiotherapy. If the metastases are still relatively small and located on the surface of the skin, ointments containing a chemotherapy drug might help too.

Metastases in the brain can be associated with severe pain. The pain may be caused by swelling or fluid building up in the brain. This can also have consequences like trouble with your sense of balance or paralysis, depending on where the metastases are. Individual brain metastases can be operated on or treated with radiotherapy. If there are several metastases in the brain, the entire brain is treated with radiotherapy. Medication can be used at the same time, for instance to reduce pain and the other effects of the swelling.

Radiotherapy can sometimes also be used in other parts of the body such as the lungs and liver, in order to relieve symptoms and temporarily slow down or stop tumor growth.

Complementary therapies

Many people would like to use complementary or “alternative” treatment approaches such as herbal medication, homeopathy or because they believe it will strengthen their self-healing powers and improve their wellbeing.

The statutory health insurance funds in Germany do not pay for most complementary therapies because there is a lack of scientific proof that they work. If you are considering having a complementary therapy, it may be worth contacting your health insurer beforehand to see whether they would cover the costs.

Some people set their hopes on alternative approaches if conventional medicine can't guarantee a cure or significant improvement (anymore). But constantly trying out new therapies can lead to repeated disappointments. You should be particularly careful when it comes to remedies or methods that are meant to be used instead of medical treatment rather than alongside it, that promise to cure the cancer and/or that are very expensive and that you have to pay for yourself.

Complementary therapies can also cause side effects. Contrary to popular belief, "herbal" does not necessarily mean "harmless." Mistletoe therapy, for instance, is not free of side effects. It is quite often used in cancer treatment despite being quite controversial.

Some complementary medicines can influence the effectiveness of other drugs, such as anesthetics and painkillers, or increase the risk of bleeding. Complementary medicines can also alter the effect of breast cancer treatment. They may reduce its effectiveness or make the side effects worse. It is therefore important to inform your doctors if you use these kinds of medicines or dietary supplements.

Palliative medicine: Living with the disease

Treatment that does not aim to cure a disease, but instead aims to help you live with it and relieve symptoms like pain, is also called “palliative treatment." Palliative treatment is often thought to be treatment and care during the last few weeks of someone’s life. But you can have palliative treatment for many months or years. Depending on the patient’s symptoms and wishes, it can already start shortly after metastatic cancer is diagnosed.

Palliative treatment, care and support can either be provided in an outpatient setting at home or in an inpatient setting. A specially trained team consisting of doctors, nurses, physiotherapists, social workers, chaplains and volunteers manages the person's care. The focus may be on coping with day-to-day activities or on accompanying someone nearing the end of life, depending on their physical and mental condition.

Counseling for cancer patients

You do not need to face the physical and mental distress caused by the disease and its treatment on your own. Coming to terms with the shock of the , dealing with fear of the future and existential questions concerning life and death is anything but easy. Accepting help can allow you to save your strength and make it easier to find ways to be able to live as good a life as possible with your disease.

Nowadays, counseling is an important part of good cancer treatment. Psycho-oncologists are specially trained psychological experts, medical experts and/or social workers. If you wish, they can support you and your family in coping with the emotional and social aspects of the disease.

In the hospital, psycho-oncological support is mainly provided by doctors and nurses. They may work together with other providers of specialized psychological support for cancer patients. Special psychological support is also offered as part of rehabilitation. Outpatient support is available for people who are at home (again). This kind of support is offered by the following specialists and facilities:

Outpatient psycho-oncology departments of hospitals and certified centers

  • Practices specialized in oncology
  • Psychosocial cancer information centers
  • Practice-based psychotherapists

Deciding not to have cancer treatment

Cancer therapies that aim to slow down or to stop cancer cell growth can have severe side effects. Some women decide not to have further treatment if their treatment is having little effect, but a lot of unpleasant side effects.

If women decide not to have treatment to fight the cancer itself, they can still have palliative treatment to relieve the pain and symptoms caused by the disease. In other words, if you decide not to have a (new) course of treatment, you will still receive medical care. You can also decide to have cancer treatment again after a treatment-free period whenever you wish.

Treatment as part of a clinical study

Clinical studies test medications and non-drug treatments and compare them with other kinds of treatment. For example, participants might be given new drugs, the effects of which are not yet completely known, or for which more experiences with larger patient groups are needed in order for them to be approved. But this does not mean that patients are exposed to incalculable risks. Clinical studies are thoroughly planned following strict quality standards, reviewed by expert committees and carried out by specialists. The effects and side effects of the drugs used are closely monitored. Patients can drop out of the study at any time.

Under certain conditions it might be possible to receive treatment as part of a clinical study. Patients receive particularly intensive care during their participation in clinical studies. But they also have to be prepared to deal with the treatment more intensively and, in many cases, to have more check-ups than usual. In order to weigh up the pros and cons of participating in a clinical study, it is important to get all the information you need and consult and coordinate things with your doctors.

In Germany, the German Society of Senology and the German Clinical Trials Register provide further information and help looking for clinical trials of breast cancer treatments.

Disease management programs

Disease management programs are structured treatment programs for people with chronic diseases. They aim to provide patients with treatments that have a scientifically proven benefit and are tailored to their individual situation. People with a chronic disease should be offered comprehensive care, advice and information. The statutory health insurance funds in Germany have offered DMPs since 2002.

The programs include regular doctor’s appointments, consultations and examinations. Participation is voluntary and does not involve any additional costs. But people who take part in a DMP commit themselves to active participation in their treatment. This includes things like seeing a doctor regularly. Doctors and medical facilities that take part in these programs commit themselves to comply with certain quality requirements. Individual statutory health insurers can be contacted to find out whether they offer a DMP for breast cancer.

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IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.

Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.

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Please note that we do not provide individual advice on matters of health. You can read about where to find help and support in Germany in our information “How can I find self-help groups and information centers?

Updated on April 7, 2016
Next planned update: 2021


Institute for Quality and Efficiency in Health Care (IQWiG, Germany)

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