Words to Know


Symptoms or signs that begin and worsen quickly and last for a short time; not chronic.


A type of cancer that starts in gland tissue, or tissue that makes and secretes a substance. The ducts and lobules of the breast are gland tissues because they make breast milk, so cancers starting in these areas are often called adenocarcinomas.


Large or swollen lymph glands.


A disease or abnormal change in a gland. Breast adenosis is a benign condition in which the lobules are larger than usual.

adjunct agent

A medicine or substance used in addition to the primary therapy.

adjunct therapy

Another treatment used together with the primary treatment. Its purpose is to assist the primary treatment. Also called adjunctive therapy.

adjunctive therapy

Another treatment used together with the primary treatment. Its purpose is to assist the primary treatment. Also called adjunct therapy.

adjuvant therapy

Cancer treatment given after surgery to lower the risk that the breast cancer will come back. Adjuvant therapy may include chemotherapy, radiation therapy, hormonal therapy, targeted therapy or biological therapy.

advance directive

A legal document that states the treatment or care a person wishes to receive or not receive if she becomes unable to make medical decisions (for example, because of being unconscious or in a coma). Some types of advance directives are living wills and do-not-resuscitate (DNR) orders.

advanced practice nurse

A registered nurse with additional education and training in how to diagnose and treat disease. Advanced practice nurses are licensed by the state and certified by national nursing organizations. In cancer care, an advanced practice nurse may manage the primary care of an individual and her or his family, based on a practice agreement with a doctor. Also called APN, NP, and nurse practitioner.

adverse effect

An unexpected medical problem that happens during treatment with a medicine or other therapy. Adverse effects do not have to be caused by the medicine or therapy, and they may be mild, moderate or severe. Also called adverse event.

aerobic exercise

Physical activity that increases the heart rate and the body's use of oxygen. It helps improve physical fitness. Aerobic exercise has been shown to help with treatment-related fatigue and insomnia. Exercise during breast cancer treatment has been shown to improve self-esteem and is being studied for its effectiveness in helping with other side effects such as chemobrain, or problems with thinking and memory.

agent study

In cancer prevention, a clinical trial that studies whether taking certain medicines, vitamins, minerals or food supplements can prevent cancer. Also called chemoprevention study. Examples of agent studies include clinical trials for tamoxifen and letrozole, as well as lifestyle changes such as diet.

aggravating factor

Something that worsens a condition. For example, diagnosis of breast cancer tends to be an aggravating factor in insomnia, and hot weather can be an aggravating factor for the existing condition of lymphedema.


Describes a tumor or disease that forms, grows or spreads quickly. It may also describe treatment that is more severe or intense than usual.

AJCC staging system

A system developed by the American Joint Committee on Cancer in which TNM is used to describe the extent of cancer in the body. T describes the size of the tumor and whether it has invaded nearby tissue. N describes whether cancer has traveled to nearby lymph nodes, and M describes whether cancer has metastasized (spread to distant parts of the body, such as the bone, liver, lungs or brain). Also called TNM staging system.


A chemotherapy medicine used in breast cancer, multiple myeloma and ovarian epithelial cancer. Alkeran is an alkylating medicine and is also called melphalan. Women should avoid becoming pregnant while taking this medicine.

alkylating agent

A type of medicine used in cancer treatment. It interferes with cell DNA and blocks cancer cell growth.


Also called fexofenadine, Allegra is an antihistamine used to treat certain allergy symptoms by blocking a chemical released during an allergic response that causes itching, sneezing, runny nose, wheezing, and watery eyes. Antihistamines are given as pretreatment when using paclitaxel, a chemotherapy agent. Antihistamines can prevent hypersensitivity reactions with paclitaxel use, such as decreased blood pressure and impaired breathing.

allopathic medicine

Another term for 'mainstream medicine,' also called biomedicine, conventional medicine, orthodox medicine, and Western medicine. Allopathic medicine is the system in which medical doctors and other healthcare professionals treat symptoms and diseases using medicines, radiation, or surgery.