Words to Know

Distant recurrence

When a primary breast cancer returns to an area of the body away from the breast, such as the lungs, liver, bones or brain. Also called metastatic breast cancer or metastatic recurrence.

Data and Safety Monitoring Board

Also called DSMB. An impartial group that oversees a clinical trial and reviews the results to see if they are acceptable. This group determines if the trial should be changed or closed.


Ductal carcinoma in situ, also called intraductal carcinoma. A noninvasive condition in which abnormal cells are found in the lining of a breast duct. The abnormal cells have not spread outside the duct to other tissues in the breast. In some cases, DCIS may become invasive cancer and spread to other tissues, although it is not known at this time how to predict which lesions will become invasive.

de novo

In cancer, the first occurrence of cancer in the body.


Surgical removal of as much of a tumor as possible. Debulking may increase the chance that chemotherapy or radiation therapy will kill all the tumor cells. It may also be done to relieve symptoms or help the individual live longer. Also called tumor debulking.

definitive surgery

Final surgery that results in negative (cancer-free) margins.

definitive treatment

The treatment plan for a disease or disorder that has been chosen as the best one for an individual after all other choices have been considered.


A condition caused by the loss of too much water from the body. Severe diarrhea or vomiting can cause dehydration. Some breast cancer treatments can cause dehydration. Symptoms of dehydration include dizziness, headache, decreased urine output, dry mouth, tiredness and listlessness or confusion. Severe dehydration requires immediate medical attention: Symptoms of severe dehydration may include passing out and urinating very little or not at all for 12 or more hours.


Also called AMG 162, Prolia and Xgeva. Denosumab is a medicine used to prevent or treat certain bone problems. In women affected with breast cancer, it may help prevent bone loss linked to use of aromatase inhibitors, a family of medicines used to treat postmenopausal women with estrogen-receptor positive disease. Under the brand name Xgeva, denosumab is used to prevent broken bones and other bone problems caused by solid tumors that have metastasized (spread) to bone. Denosumab binds to a protein called RANKL, and keeps RANKL from binding to another protein called RANK, on the surface of certain bone cells. This may help keep bone from breaking down. Denosumab is a type of monoclonal antibody.


A mental condition marked by ongoing feelings of sadness, despair, loss of energy and difficulty dealing with normal daily life. Other symptoms include feelings of worthlessness and hopelessness, loss of pleasure in activities, changes in eating or sleeping habits and thoughts of death or suicide. Depression can affect anyone and can be successfully treated.


The process of identifying a disease, such as breast cancer, from its signs and symptoms.

diagnostic mammogram

X-ray of the breasts used to check for breast cancer after a lump or other sign or symptom of breast cancer has been found.

diagnostic procedure

A specific test or series of steps done to help diagnose a disease or condition. Mammograms are one example of a diagnostic procedure.

diagnostic technique

A type of method or test used to help diagnose a disease or condition. Imaging tests and tests to measure blood pressure, pulse and temperature are examples of diagnostic techniques.

diagnostic trial

A research study that evaluates methods of detecting disease.


The length of a straight line that extends from one edge of a tumor or other object, through its center and to the opposite edge. It is usually used to measure the size of round or spherical shapes.


Frequent and watery bowel movements.


Also called AZQ. An anticancer drug that is able to cross the blood-brain barrier and kill cancer cells in the central nervous system.

DIEP flap

A type of breast reconstruction in which blood vessels called deep inferior epigastric perforators (DIEP), and the skin and fat connected to them, are removed from the lower abdomen and used for reconstruction. Muscle is left in place.

dietary counseling

Also called nutritional counseling. A process by which a health professional with special training in nutrition helps with healthy food choices and forming healthy eating habits. In breast cancer treatment, the goal of dietary counseling is to help individuals stay healthy during and after treatment and to stay strong enough to fight infections and help prevent the recurrence of disease.

dietary supplement

Also called nutritional supplement. A product that is added to the diet. A dietary supplement is taken by mouth and usually contains one or more dietary ingredient (such as vitamin, mineral, herb, amino acid and enzyme).


A health professional with special training in nutrition who can help with dietary choices. Also called nutritionist.


In breast cancer, refers to how mature (developed) the cancer cells are in a tumor. Differentiated tumor cells resemble normal cells and tend to grow and spread at a slower rate than undifferentiated or poorly differentiated tumor cells, which lack the structure and function of normal cells and grow uncontrollably.


Widely spread; not localized or confined.

digital mammography

The use of a computer, rather than X-ray film, to create a picture of the breast.


An antihistamine medicine sold over the counter under the brand name Benadryl. It is used to treat allergies, and is commonly present in over the counter sleep aids. Diphenhydramine may reduce the effects of tamoxifen, a medicine prescribed to reduce the likelihood of breast cancer recurrence. Talk with your doctor for more information.


Fluid that comes out of the body, sometimes from one or both nipples of the breast. Discharge can be normal or a sign of disease in women, but is a reason to seek medical attention. In men, discharge from the nipples requires medical attention. A second meaning for 'discharge' is the release of an individual from care at a hospital or health care facility.

disease progression

The length of time after treatment for breast cancer during which an individual survives with no sign of the disease. Disease-free survival may be used in a clinical study or trial to help measure how well a new treatment works.

disease-specific survival rate

The percent of people in a study or treatment group who have not died from a specific disease in a defined period of time. The time period usually begins at the time of diagnosis or at the start of treatment and ends at the time of death. Individuals who died from causes other than the disease being studied are not counted in this measurement.

distant cancer

Also known as distant metastasis. Refers to cancer that has spread from the original (primary) tumor to distant organs or distant lymph nodes.

distant metastasis

Also known as distant cancer. Refers to cancer that has spread from the original (primary) tumor to distant organs or distant lymph nodes.


Extreme mental or physical pain or suffering.

DNR order

Also called do not resuscitate order. A type of advance directive in which a person states that healthcare providers should not perform cardiopulmonary resuscitation (CPR) to restart the heart if his or her heart or breathing stops.


Also called Taxotere. A medicine used together with other agents to treat certain types of breast cancer, stomach cancer, prostate cancer and certain types of head and neck cancer. It is also being studied in the treatment of other types of cancer. Docetaxel is a type of mitotic inhibitor.


Brand name Anzemet. Dolasetron is a medicine used to treat nausea and vomiting caused by breast cancer treatment. It is a type of serotonin receptor antagonist and a type of antiemetic. Also called dolasetron mesylate.

dose-dense chemotherapy

A chemotherapy treatment plan in which medicines are given with less time between treatments than in a standard chemotherapy treatment plan.


Refers to the effects of treatment with a medicine. If the effects change when the dose of the medicine is changed, the effects are said to be dose-dependent.


Describes side effects of a medicine or other treatment that are serious enough to prevent an increase in dose or level of that treatment.


The strength of a treatment given over a period of time.


The amount of medicine taken, or radiation given, at one time.


A clinical trial in which the medical staff, the participant and the people who analyze the results do not know the specific type of treatment the individual receives until after the clinical trial is over.


A medicine that is used to treat many types of cancer. Doxorubicin comes from the bacterium Streptomyces peucetius. It damages DNA and may kill cancer cells. It is a type of anthracycline antitumor antibiotic. Also called Adriamycin PFS, Adriamycin RDF, doxorubicin hydrochloride, hydroxydaunorubicin and Rubex.


In medicine, to remove fluid as it collects; or, a tube or wick-like device used to remove fluid from a body cavity, wound or infected area. Drains are sometimes required after mastectomy.


A synthetic pill form of delta-9-tetrahydrocannabinol (THC), an active ingredient in marijuana that is used to treat nausea and vomiting associated with breast cancer chemotherapy.


A medicine used to prevent nausea and vomiting in individuals who receive anesthesia before surgery. It is also used to treat anxiety. Droperidol is a type of antiemetic, adjunct anesthesia and antipsychotic.

drug interaction

A change in the way a medicine acts in the body when taken with certain other medicines, herbs or foods, or when taken with certain medical conditions. Drug interactions may cause the medicine to be more or less effective, or cause effects on the body that are not expected.

drug resistance

The failure of cancer cells, viruses, or bacteria to respond to a medicine used to kill or weaken them. The cells, viruses, or bacteria may be resistant to the agent at the beginning of treatment, or may become resistant after being exposed to the medicine.

drug therapy

Treatment with any substance other than food, that is used to prevent, diagnose, treat or relieve symptoms of a disease or abnormal condition.

drug tolerance

A condition that occurs when the body gets used to a medicine, so that either more medicine is needed or different medicine is needed.

ductal carcinoma

The most common type of breast cancer. It begins in the cells that line the milk ducts in the breast.

ductal carcinoma in situ

A noninvasive condition in which abnormal cells are found in the lining of a breast duct. The abnormal cells have not spread outside the duct to other tissues in the breast. In some cases, ductal carcinoma in situ may become invasive cancer and spread to other tissues, although it is not known at this time how to predict which lesions will become invasive. Also called DCIS and intraductal carcinoma.

ductal lavage

A method used to collect cells from milk ducts in the breast. A hair-size catheter (tube) is inserted into the nipple, and a small amount of salt water is released into the duct. The water picks up breast cells, and is removed. The cells are checked under a microscope. Ductal lavage may be used in addition to clinical breast examination and mammography to detect breast cancer.


In medicine, a tube or vessel of the body through which fluids pass. In the female anatomy, passageways that carry milk from the lobules in the breast to the nipple.


A drug used to treat depression and peripheral neuropathy (pain, numbness, tingling, burning or weakness in the hands or feet) that can occur with diabetes. It is also being studied in the treatment of peripheral neuropathy caused by certain anticancer drugs. Duloxetine increases the amount of certain chemicals in the brain that help relieve depression and pain. It is a type of serotonin and norepinephrine reuptake inhibitor. Also called Cymbalta and duloxetine hydrochloride.

durable power of attorney

Also called DPA. A type of power of attorney. A power of attorney is a legal document that gives one person (such as a relative, lawyer or friend) the authority to make legal, medical or financial decisions for another person. It may go into effect right away, or when that person is no longer able to make decisions for himself or herself. A durable power of attorney remains in effect until the person who grants it dies or cancels it. It does not need to be renewed over time.


A state of not functioning normally.


A bad taste in the mouth. Also called parageusia.


Upset stomach.


Difficult, painful breathing or shortness of breath.