Chemotherapy for Metastatic Breast Cancer

Chemotherapy is used as a treatment for most people who have metastatic breast cancer. Whether it is used first-line or not depends on your receptor status, previous treatments, and other factors.

This article will discuss how chemotherapy in metastatic breast cancer works, when it's used, different types, and its side effects.

How It Works

Chemotherapy works by attacking rapidly growing cells such as cancer cells. Most of the chemotherapy drugs interfere with cancer cells at some point in the division process, but different phases of the cell cycle are interrupted with different drugs.

Since these treatments affect any rapidly growing cells, they also frequently damage normal cells in the body, such as those in the digestive tract (which can cause nausea), hair follicles (which can cause hair loss), and bone marrow (which results in anemia and low white blood cell counts).

When It Is Used

How soon chemotherapy is recommended for treatment depends on the particular type of breast cancer you have, whether or not your tumor is estrogen receptor or HER 2 receptor-positive, and whether or not hormonal therapies are effective for your tumor.

Chemotherapy is usually recommended as the first-line metastatic cancer treatment for:

  • People who have estrogen-receptor-positive tumors that have become resistant to hormonal medications such as tamoxifen or aromatase inhibitors
  • People who have HER2 positive tumors (along with targeted therapy such as Herceptin) that are estrogen receptor-negative
  • People who have tumors that are both estrogen receptor and HER2 negative (triple-negative breast cancers)
  • Cases in which hormonal therapies are effective against estrogen receptor-positive tumors and a rapid reduction in the tumor is needed


You can expect to have your chemotherapy in cycles that are spaced 21 to 28 days apart. The number of cycles you receive will depend on many things, including your response to the drug or drugs.

Chemotherapy can work very well for metastatic breast cancer, although tumors almost always become resistant to any given drug or combination of drugs over time. It is not uncommon for people to undergo at least three different chemotherapy regimens during treatment.

Your chemotherapy for metastatic breast cancer may be dosed either continually (one combination of drugs after another without a break) or intermittently, and there are pros and cons to each method.

  • It’s been found that continuous chemotherapy may slow the growth of cancer somewhat more effectively than intermittent therapy, although there doesn’t appear to be a big difference in overall survival.
  • In contrast, those who receive intermittent therapy tend to have a better overall quality of life. It is for many reasons such as this that your oncologist will want to understand your personal preferences with regard to managing your cancer.


The goals of chemotherapy treatment for metastatic breast cancer are usually different than the goals of chemotherapy treatment for early-stage disease, and this can be very confusing.

For early-stage breast cancer, chemotherapy is most often intended to cure the disease. For example, chemotherapy after breast cancer surgery is intended to attack any remaining cancer cells in the body that cannot be seen on imaging studies, with the goal that cancer will be cured. Used in this way, chemotherapy is referred to as adjuvant therapy.

You might have chemotherapy for early-stage breast cancer to decrease the size of a tumor before surgery. Used in this way, chemotherapy is referred to as neoadjuvant therapy, and the goal is also a cure.

Chemotherapy for metastatic breast cancer, however, is used with different goals.

These goals are:

  • To extend your life
  • To improve your quality of life
  • To ease your symptoms

Chemotherapy for metastatic breast cancer is not expected to cure the disease, but instead to control the disease for as long as possible.

Why Isn’t a Cure the Goal?

It can be painful and shocking when you come to understand the differences between what chemotherapy may offer for early-stage breast cancer and what it may accomplish for metastatic breast cancer.

It is not that healthcare providers don’t want to attempt to cure advanced breast cancer with chemotherapy. They do. It’s just that with the drugs we currently have, and the resistance which develops over time, the odds of chemotherapy curing an advanced cancer are very low. This is true even if you are treated with extremely high doses of several powerful drugs.

According to studies, many people who have breast cancer are expecting that chemotherapy will cure their metastatic cancer. There are some cancers that respond and continue to respond to chemotherapy for a long time. Still, it’s important to understand what chemotherapy can and can’t do with the drugs we currently have.

If you are still hoping for a cure, talk to your healthcare provider. At this time there are not any approved medications that can cure metastatic breast cancer, though new medications are always being evaluated in clinical trials. For a few people, some of these newer medications, such as immunotherapy drugs, may offer a greater chance for long-term survival—but we don’t know for sure, and that is why they're being studied.

Breast Cancer Healthcare Provider Discussion Guide

Get our printable guide for your next healthcare provider's appointment to help you ask the right questions.

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Chemotherapy Drugs

If your cancer is a recurrence and you had chemotherapy the first time around, different drugs are usually used. It’s thought that the cancer cells that persist beyond your initial treatment are likely resistant to the medications. The chemotherapy may have killed off many cancer cells but the remaining cells that were resistant to the drug were left behind.

It’s not uncommon for someone to have at least three separate chemotherapy regimens to treat their cancer. To differentiate these treatments, oncologists usually refer to a chemotherapy regimen as the first line, second line, third line, and so on.

Chemotherapy tends to become less effective over time as more regimens are needed.

Categories of Medications

Several different categories of chemotherapy medications can be used, to treat breast cancer including:

  • Anthracyclines: Adriamycin (doxorubicin), Ellence (epirubicin)
  • Alkylating agents: Cytoxan (cyclophosphamide)
  • Taxanes: Taxol (paclitaxel), Taxotere (docetaxel), Abraxane (nab-paclitaxel)
  • Mitotic inhibitors: Halaven (eribulin)
  • Nucleoside analog drugs: Gemzar (gemcitabine) and DNA synthesis inhibitors Xeloda (capecitabine)
  • Antimetabolites: methotrexate
  • Microtubule inhibitors: Ixempra (ixabepilone), Navelbine (vinorelbine)
  • Platinum drugs: Platinol (cisplatin), Paraplatin (carboplatin)
chemotherapy infusion
 Verywell / JR Bee

Single vs. Combination Therapy

Unlike adjuvant therapy for early-stage breast cancer, which almost always entails using a combination of drugs, single-agent therapy is often used for metastatic breast cancer. The use of combination chemotherapy is usually limited to times when cancer is rapidly progressive.

A few combinations that are commonly used include Xeloda (capecitabine) and Taxotere (docetaxel), and Gemzar (gemcitabine) and Taxol (paclitaxel).

Brain Metastases

While chemotherapy is able to treat cancer cells nearly everywhere in the body, many chemotherapy medications can't reach the brain. This is because of a specialized membrane of capillaries known as the blood-brain barrier.

The blood-brain barrier is designed to prevent toxins from entering the sensitive tissues of the brain and spinal cord and it may also prevent chemotherapy drugs from gaining access. Other treatment options, such as whole-brain radiotherapy or stereotactic brain radiation may be needed to treat breast cancer that has spread to the brain.

Common Side Effects

There have been significant advances in managing the side effects of chemotherapy in recent years, especially symptoms such as nausea and vomiting.

The specific side effects of the different drugs can vary, and it’s important to talk to your healthcare provider about possible adverse reactions.


Fatigue is one of the most common chemotherapy side effects, and one of the more frustrating. Even though we don’t yet have any specific treatments for fatigue, there are many things you can do to make it more tolerable.

Simple measures, such as pacing yourself through the day, prioritizing activities, and learning to delegate can be very helpful. Learning to delegate, and ask for and receive help may not only help you with your fatigue but will allow your loved ones a way to cope with their feelings as they try to be supportive.

Hair Loss

Hair loss is common with many chemotherapy drugs. You might consider getting a wig. Insurance often covers a portion of this, and several organizations provide free wigs from donated hair. Scarves and hats are also an option and might be more comfortable for you.

In recent years, researchers have looked at methods of preventing hair loss. While these methods, such as wearing an ice cap during your infusion, may decrease your hair loss, they can be very uncomfortable.

Nausea and Vomiting 

Many of the drugs used for treating metastatic breast cancer can cause nausea and vomiting. There are many ways to manage this. In fact, there are now many people who experience little or even no nausea related to cancer treatment.

Some prescribed medications can prevent nausea, and others can be used to treat nausea. Make sure to talk to your healthcare provider if you experience nausea.

One medication may work better for you than others, so it's important that you let your healthcare provider know how well it's working.

You may hear people talk about acupressure bands, ginger, and other alternative therapies for chemotherapy-induced nausea. While these measures may have some effect, they should be used only as an add-on to anti-nausea medications, and not as a substitute.

Diarrhea may also manifest as a side effect. Work with your healthcare provider to review what you can do to decrease it.

Bone Marrow Suppression 

The effect of chemotherapy drugs on bone marrow can lead to decreased levels of all the types of blood cells produced in the bone marrow. This can include red blood cells (leading to anemia), white blood cells (leading to leukopenia or neutropenia), and platelets (leading to thrombocytopenia).

Anemia can contribute to your fatigue. A low platelet count may increase your risk of bleeding. If your level is low, it’s a good idea to avoid activities that could result in bleeding or bruising.

A low white blood cell count can predispose you to infections that would otherwise be harmless. This can also make it more difficult for you to fight infection once it occurs. If you develop a fever while on chemotherapy (even one as low as 100.5) it is important to call your healthcare provider right away.

These infections can usually be treated, and prompt treatment can make a big difference. Your healthcare provider will talk to you about methods of reducing infection. People who are taking chemotherapy—whether or not their white blood cell count is low—are often told to avoid crowded places (especially during the winter months and flu season) and to minimize contact with loved ones who are ill.

With some of the chemotherapy drugs, your healthcare provider may prescribe a medication to increase your white blood cell count.

Peripheral Neuropathy 

Some chemotherapy drugs can cause peripheral neuropathy. Symptoms may include burning, tingling, and numbness which occur in a “stocking and glove” distribution on the hands and feet.

Since the decreased sensation in your feet may interfere with walking and balance, look around your home environment to minimize their chances of a fall, avoid obstacles such as throw rugs, and practice caution when walking in ice and snow.

While peripheral neuropathy may improve over time, some of these symptoms may be permanent after you complete your chemotherapy treatment.

A Word From Verywell

Most people will have chemotherapy at some point during the treatment of metastatic breast cancer, and some will have several lines of chemotherapy. It's important to understand that the goals of chemotherapy for stage 4 breast cancer are much different than those for early-stage disease, and it's not uncommon to be treated with only one rather than a combination of drugs.

12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading
  • DeVita, Vincent., et al. Cancer: Principles & Practice of Oncology. Cancer of the Breast. Wolters Kluwer.

By Lynne Eldridge, MD
 Lynne Eldrige, MD, is a lung cancer physician, patient advocate, and award-winning author of "Avoiding Cancer One Day at a Time."