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Treating Early-Stage Breast Cancer

Therapy for early-stage breast cancer aims to lower the chance that cancer will come back.

A variety of treatments are available for early-stage breast cancer. Most options depend on the staging of the cancer and specific pathology of the tumor. Your personal preferences play an important part too.


Surgery to remove a tumor is usually the first step in treating early-stage breast cancer. It is the oldest and most effective way to treat cancer. Surgery usually involves a lumpectomy or mastectomy. Even with successful surgery and clear lymph nodes, there is still a chance that the tumor could have spread elsewhere. So, some kind of adjuvant therapy usually comes next.

Adjuvant Therapy

Adjuvant therapy is any anti-cancer treatment given after surgery. The goal of adjuvant therapy is to get rid of any cancer left behind after surgery. It is an important part of treatment for early-stage breast cancer. Adjuvant therapy greatly lowers the chance of cancer coming back. It also improves the overall chance of survival. Two common kinds of adjuvant therapy for breast cancer are:

Making choices about adjuvant therapy can be confusing. There are benefits and risks for either therapy (described below). Each person and cancer is unique, so there isn't always a treatment that is clearly best. Oncotype DX® gives you another piece of information about your tumor that may help make these treatment decisions more clear.

Hormone Therapy

Hormones stimulate certain tissues, like breast tissue, to grow. Cells control what hormones can affect them through cell receptors. Cell receptors only recognize specific hormones, much like a key fitting into a lock. Normal breast tissue has many receptors for estrogen and progesterone, often called ER (estrogen receptors) and PR (progesterone receptors) for short.

When a cell becomes cancerous, it changes how the cell works. Breast cancer cells may lose their normal hormone receptors. When this happens, cancer cells are unable to recognize estrogen and progesterone. The key has lost its matching lock. This is called hormone negative cancer, or ER/PR-.

Breast cancers that keep their hormone receptors are called hormone positive, or ER/PR+. About 50% to 70% of all breast cancers are ER/PR+. The difference between ER/PR+ and ER/PR- cancer is important for figuring out the best treatment.

ER/PR+ tumors respond well to targeted hormone therapies, like tamoxifen and aromatase inhibitors (AIs). Tamoxifen and AIs block estrogen and progesterone receptors. This stops the key from fitting into its lock. Because estrogen and progesterone encourage the cell to grow, tamoxifen and AIs stop cancer growth by shutting off the fuel supply.

Hormone therapy is the most effective breast cancer treatment available. In addition to treating the initial breast cancer, it also helps stop cancer from coming back. Treatment usually lasts for five years. It is, however, not without side effects and risks. Side effects of hormone therapy mimic those of menopause. Risks of treatment include various types of uterine cancer.

Oncotype DX test results can help decide if tamoxifen therapy is all you need. Tumors with Low Recurrence Scores actually show the greatest benefit from hormone therapy.


Chemotherapy works by killing all fast-growing cells in the body. Because cancer cells grow at a fast rate, they are especially vulnerable to chemotherapy. The advantage of chemotherapy is that it can travel throughout the body. It can kill cancer cells that have spread. Unfortunately, chemotherapy also kills healthy cells. The damage to healthy cells is what leads to the side effects and risks of chemotherapy.

Adjuvant chemotherapy usually begins within six weeks after surgery. Treatment usually lasts between three and six months. CMF and anthracycline are the most common chemotherapies used for early-stage breast cancer. In addition, taxane has recently been approved for higher-risk, early-stage breast cancers. In general, chemotherapy is finished before starting hormone therapy.

Chemotherapy for early-stage breast cancer is controversial. ER/PR+, early-stage breast cancer tends to have a good prognosis without chemotherapy. The risks of chemotherapy outweigh the benefits for most people. However, some early-stage tumors are higher risk and adjuvant chemotherapy is helpful. Until recently, it was hard to know which patients had a higher risk.

Oncotype DX test results can help figure out which people with early-stage breast cancer have a higher risk and should consider chemotherapy.

Next: Staging Breast Cancer