Words to Know


The edge or border of the tissue removed in cancer surgery. The margin is described as negative, or clean, when the pathologist finds no breast cancer cells within it, which suggests that all of the cancer has been removed. The margin is described as positive, or involved, when the pathologist finds cancer cells within it, which suggests that all of the cancer has not been removed.


A diagnostic indication that disease may develop.

massage therapy

A treatment in which the soft tissues of the body are kneaded, rubbed, tapped and stroked. Massage therapy may help people relax, relieve stress and pain, lower blood pressure and improve circulation. Therapeutic massage is being studied in the treatment of cancer symptoms such as pain and depression.


In medicine, a lump in the body. It may be caused by the abnormal growth of cells, a cyst, hormonal changes or an immune reaction. A mass may be benign (noncancerous) or malignant (cancerous).


Surgery to remove the whole breast, or as much of the breast tissue as possible.


A painful condition in which breast tissue is inflamed. It is usually caused by an infection and is most often seen in nursing mothers. The symptoms of mastitis are similar to the symptoms of inflammatory breast cancer. Those symptoms include breast enlargement (on one side only) and pain, enlarged lymph nodes in the armpit, flu-like symptoms, itching, lump, nipple discharge, redness and swelling. Fever is a symptom of mastitis that is not common to inflammatory breast cancer.


Having to do with the mother, coming from the mother or related through the mother.

maximum tolerated dose

Also called MTD. The highest dose of a medicine or treatment possible that does not unacceptable side effects. The maximum tolerated dose is determined in clinical trials by testing increasingly higher doses on different groups of people, until the highest dose with acceptable side effects is found.

mean survival time

The average time that individuals in a clinical study remained alive. The time is measured beginning either at diagnosis, or at the start of treatment.

measurable disease

A tumor that can be accurately measured in size. This information can be used to judge response to treatment.

medial supraclavicular lymph node

A lymph node located above the collar bone and between the center of the body and a line drawn through the nipple to the shoulder.

median survival time

The time from either diagnosis or the start of treatment at which half of the participants with a given disease either are or are expected to be living. In a clinical trial, median survival time is one way to measure how effective a treatment is.


A statistics term. The middle value in a set of measurements.


A health insurance program for people who cannot afford regular medical care. The program is run by U.S. federal, state, and local governments. People who receive Medicaid may have to pay a small amount for the services they get. Breast and cervical cancer screenings and treatments are listed as an option for coverage through Medicare.

medical castration

Refers to the use of medicines to slow or stop the function of the ovaries.

medical device

An instrument, tool, machine, test kit, or implant that is used to prevent, diagnose, or treat disease or other conditions. Medical devices range from tongue depressors to medical imaging equipment.

medical nutrition therapy

Also called nutrition therapy. Treatment based on nutrition. It includes checking a person's nutrition status and giving the right foods or nutrients to treat conditions such as side effects caused by breast cancer treatment. Therapy may involve simple changes in a person's diet, or feeding someone intravenously or through a tube. Medical nutrition therapy may help individuals recover more quickly and spend less time in the hospital.

medical oncologist

A doctor who specializes in diagnosing and treating cancers using chemotherapy, hormonal therapy, biological therapy and targeted therapy. A medical oncologist is often the main health care provider for someone who has breast cancer. A medical oncologist also gives supportive care and may coordinate treatment given by other specialists.


A U.S. federal health insurance program for people aged 65 years or older and people with certain disabilities. Medicare pays for hospital stays, medical services and some prescription medicines, but people who receive Medicare must pay part of their healthcare costs.


Refers to the practices and procedures used for the prevention, treatment, or relief of symptoms of a diseases or conditions that impact health. This term may also refer to a legal medicine, used for the same purpose.