The breast and cancerAbout breast cancer

There are many types of cancer. As with all cancers, affected cells in the body change and grow out of control.

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What is cancer?

  • Usually, the multiplying cancer cells form a lump called a tumor
  • Not all tumors are cancerous. Tumors that are not cancerous are called benign (pronounced beh-NINE) tumors. Cells from benign tumors do not spread to other parts of the body
  • Cancerous tumors are called malignant tumors. Sometimes malignant tumor cells can break away from the original, primary tumor and travel through the bloodstream or lymphatic system to other parts of the body. This process is called metastasis (pronounced meh-TAS-tuh-sis)
  • Cancer is usually named after the part of the body where it first develops: the primary site. Breast cancer begins in the breast tissue. If it spreads to the lungs, for example it is still considered breast cancer, not lung cancer
  • Doctors use the term "stage" to refer to the extent of cancer within the body. Knowing the stage of cancer can help you and your doctor determine your best treatment plan
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About breast cancer

Doctors classify breast cancer as early or advanced depending on where the cancer is and how far it has spread.

  • Early breast cancer occurs when the cancer is contained within the breast without spreading to the skin of the breast, or tissues of the chest wall, and hasn't spread to distant locations. Early breast cancer may have spread to some lymph nodes such as those found under the arm. Find out more about treatments for early breast cancer
  • Advanced breast cancer occurs when the cancer has spread from its original place within the breast to surrounding tissues, such as the skin above or muscle below the breast, or to distant areas of the body. Advanced breast cancer can be classified: locally advanced or metastatic.

    Locally advanced breast cancer
    The term locally advanced breast cancer indicates that the cancer is large (greater than 2 inches) and/or may have spread to other nearby tissue, such as lymph nodes or the skin above or muscle below the breast

    Metastatic breast cancer
    The term metastatic breast cancer indicates that the cancer has spread from the breast to other parts of the body, such as the bone, lungs, liver, or brain
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Important Information About ARIMIDEX

ARIMIDEX is approved for adjuvant treatment (treatment following surgery with or without radiation) of postmenopausal women with hormone receptor-positive early breast cancer.

ARIMIDEX is approved for the initial treatment of postmenopausal women with hormone receptor-positive or hormone receptor-unknown locally advanced or metastatic breast cancer and for the treatment of postmenopausal women with advanced breast cancer that has progressed following treatment with tamoxifen. Patients with hormone receptor-negative disease and patients who did not previously respond to tamoxifen therapy rarely responded to ARIMIDEX.

Important Safety Information About ARIMIDEX

  • Prescription ARIMIDEX is only for postmenopausal women. ARIMIDEX should not be taken if you are pregnant because it may harm your unborn child
  • Based on information from a study in patients with early breast cancer, women with a history of blockages in heart arteries (ischemic heart disease) who take ARIMIDEX may have a slight increase in this type of heart disease compared to similar patients who take tamoxifen
  • ARIMIDEX can cause bone softening/weakening (osteoporosis) increasing the chance of fractures. In a clinical study in early breast cancer, there were more fractures (including fractures of the spine, hip, and wrist) with ARIMIDEX (10%) than with tamoxifen (7%)
  • In a clinical study in early breast cancer, some patients taking ARIMIDEX had an increase in cholesterol. Skin reactions, allergic reactions, and changes in blood tests of liver function have also been reported
  • In the early breast cancer clinical trial, the most common side effects seen with ARIMIDEX include hot flashes, joint symptoms (including arthritis and arthralgia), weakness, mood changes, pain, back pain, sore throat, nausea and vomiting, rash, depression, high blood pressure, osteoporosis, fractures, swelling of arms/legs, insomnia, and headache
  • In advanced breast cancer trials, the most common side effects seen with ARIMIDEX versus tamoxifen include hot flashes, nausea, decreased energy and weakness, pain, back pain, headache, bone pain, increased cough, shortness of breath, sore throat, and swelling of arms and legs. Joint pain/stiffness has been reported in association with the use of ARIMIDEX
  • ARIMIDEX should not be taken with tamoxifen or estrogen-containing therapies

Please click here for full Prescribing Information.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.FDA.gov/medwatch or call 1-800-FDA-1088 (1-800-332-1088).