Breast Cancer: Systemic Therapy

Pictured: Diana Lake Medical oncologist Diana Lake is involved in clinical trials to develop better hormonal therapies and other medical approaches to treatment before surgery for breast cancer.

Systemic therapy is the use of drugs that spread throughout the body to eliminate cancer cells wherever they are. It includes chemotherapy, hormonal therapy, biologic agents, and vaccines. At Memorial Sloan Kettering, your healthcare team has extensive experience in treating patients with systemic therapies and will help you to anticipate and manage the side effects of your treatment.

We’re a leading center for the development of innovative systemic therapies for breast cancer. Most of the effective forms of this type of treatment for the disease that have been developed in the past decade were studied and explored by members of our medical oncology team.

After surgery, some women need adjuvant (additional) systemic therapy. The goal of this treatment is to reduce the risk of breast cancer recurring (coming back) or metastasizing (spreading). Sometimes we give this treatment before surgery (an approach called neoadjuvant therapy) to help shrink the tumor and make it easier to remove surgically.

Whether you would benefit from adjuvant therapy and which type best suits your condition depends on such factors as:

  • the presence or absence of cancer cells in your lymph nodes
  • the size of the tumor
  •  your menopausal status
  • whether your tumor contains hormone receptors or overproduces certain proteins, such as HER2/neu
  • whether you have a high recurrence score on OncotypeDx® testing, which analyzes the activity of a group of genes that can influence how cancer might behave or respond to different treatments.

We may also recommend a clinical trial of an investigational new treatment for you.

Women with metastatic breast cancer may receive various systemic therapies — chemotherapy, hormonal therapy, targeted agents, or combinations of these — to control the disease. The choice of treatments depends on certain characteristics of the tumor, such as hormone receptors, HER2/neu status, and the location of the disease.

Side Effects of Systemic Therapy

In addition to cancer cells, normal cells are sometimes affected by systemic therapy because these drugs cannot distinguish one from the other. This can result in undesired side effects. However, everyone responds differently to various therapies. Some women experience side effects, while others have none. The absence of side effects does not mean your treatment isn’t working.

Learn more about the systemic therapies we offer.

Chemotherapy
Chemotherapy drugs can help you fight breast cancer by interrupting the growth of cancer cells. We offer supportive medicines for treatment side effects.

Hormone Therapy
Since some breast cancers rely on estrogen and other hormones to fuel their growth, medicines that block or stop this can potentially help counter the cancer.

Targeted Therapy
A current focus of breast cancer research is to find drugs that work by targeting specific molecules involved in breast cancer development.