What stage of breast cancer needs chemotherapy?

Chemotherapy may be recommended in breast cancer stages I to IV where it has invaded the lymph nodes. This will lower the chances of the cancer spreading in the body. Chemotherapy may also be used to treat breast cancer that has returned after a primary treatment.

Chemotherapy may be recommended less often for women who have no cancer detected in the axillary (armpit) lymph nodes (node-negative breast cancer), especially if the cancer is estrogen-receptor positive and can be treated with oral hormone therapy. In some cases, postmenopausal women with a low risk of breast cancer recurrence and few positive lymph nodes may not need chemotherapy.

Chemotherapy is not necessary for women with ductal carcinoma in situ (DCIS), which is considered stage 0, and has no lymph node involvement.

Your cancer doctor (oncologist) can determine if you need chemotherapy and which regimen is best for you. Chemotherapy may be given before or after surgery. Treatment is always individualized.

Whether or not you need chemotherapy will be determined by the stage, size and type of breast cancer you have, including if it has spread. Your doctor will also look at whether the cancer is hormone (estrogen and progesterone) receptor positive, is associated with HER2 proteins, or is triple negative.

Treatment will also be based on your overall health and age and personal preferences.

Related: What drugs are used to treat breast cancer?

Your doctor may order a test called the 21 gene test (for example, the Oncotype DX), a type of genetic test, if your breast cancer is hormone (estrogen or progesterone) positive, HER2-negative, and node negative. This test, which assigns a score of 1 to 100, helps to predict the chance of breast cancer recurrence and if chemotherapy may be beneficial for you.

What does chemotherapy do?

Chemotherapy slows or stops the growth of the primary tumor and other cancer cells that may have metastasized (spread in your body). It may be used to shrink the tumor before surgery or to treat any remaining cancer cells in the body after surgery. Chemotherapy drugs reach almost all areas of the body. Some chemotherapy drugs are used in combination because they work in different ways and may be more effective.

Chemotherapy is usually given into a vein (intravenously or IV) and may cause side effects such as nausea, hair loss, tiredness, and trouble with focusing and memory (“brain fog”). Your doctor can help to reduce some of these side effects, such as nausea, and hair loss is almost always temporary.

What are breast cancer stages?

Stages of breast cancer are designated as Stage 0 through Stage IV and recurrent breast cancer. Staging of breast cancer is used by doctors to describe if the cancer has spread, how far it has spread, and to help determine a treatment plan.

Staging is determined by using a combination of a physical exam, a mammogram (or other imaging test) and sizing of tumor, and examination of the tumor and lymph nodes after surgical removal. Treatment will be determined based on the size of the tumor, grade of the disease, and health of the woman.

Staging uses the TNM designation and stages 0 through IV. “TNM” staging system (or “Tumor”, “Node”, “Metastatic”) helps to describe the tumor stage. Stage 0 is the least advanced cancer while Stage IV is the most advanced. Treatment will be determined based on the size of the tumor, grade of the disease, and health of the woman. The tumor “Grade” (grade 1-3) describes how fast a tumor grows, with 1 being the slowest and 3 the fastest.

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List of breast cancer stages

Stage 0: Ductal carcinoma in situ (DCIS) alone, is considered non-invasive cancer, meaning it is localized to the original area and has not spread into the lymph nodes. This type of cancer is limited to the cells of the milk ducts but has not invaded nearby tissues. A lumpectomy and radiation therapy may be recommended at this stage of breast cancer.

Chemotherapy is not necessary for women with DCIS, but oral hormone therapy may be recommended to help prevent the cancer from returning.

Stages I or II: These stages of breast cancer are considered early-stage localized breast cancer. The tumor size and lymph node-status (positive or negative) are used to distinguish between Stage I or II. Surgical options may include mastectomy (surgical removal of the breast) or lumpectomy (removal of tumor only instead of entire breast) may be treatment options.

Chemotherapy may be recommended less often for women who have no cancer detected in the axillary (armpit) lymph nodes (node-negative breast cancer), especially if the cancer is estrogen-receptor positive and can be treated with oral hormone therapy.

Stage III: This stage is considered locally advanced breast cancer. Tumor size is larger with cancer found in multiple lymph nodes.

Stage IV: Cancer that has spread (metastasized) from the breast and lymph nodes to other areas or organs in the body, such as the bones, lungs or liver.

Most women with estrogen-receptor (ER)-positive breast cancer will take adjuvant (after surgery) oral hormone therapy, such as:

• tamoxifen
• raloxifene
• Arimidex (anastrozole)
• Aromasin (exemestane)
• Femara (letrozole).

Hormone therapy is used long-term (5 to 10 years) can reduce the chance that breast cancer will return by 50%, prolong the time until breast cancer comes back, or limit how far it spreads in the body if it does return. Hormone therapy is not the same as chemotherapy and has fewer side effects.

Is targeted drug therapy used for breast cancer treatment?

Targeted drug therapies may also be selected for certain types of breast cancer. These are more specific treatments that help the body’s immune system to target and kill breast cancer cells with certain attributes. Targeted therapy may work if chemotherapy does not in some cases.

For example, in HER2 positive breast cancer, targeted drug treatments such as trastuzumab (Herceptin), pertuzumab (Perjeta), ado-trastuzumab emtansine (Kadcyla), and lapatinib (Tykerb) are used. The side effects of HER2 targeted therapy are often mild, but some can be more serious. Talk with your doctor about what type of side effects you can expect.

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