Glossary of Terms

Introduction

Parts of this glossary have been taken or adapted from the National Cancer Institute’s Cancer Dictionary and the American Breast Cancer Society’s Breast Cancer Dictionary.

This glossary does not contain definitions of medications. To learn more about specific medications, visit the website of the National Cancer Institute.

Many thanks to the healthcare practitioners who reviewed portions of this glossary:

• Mechelle Barrick, RN, BSN, OCN, Greater Baltimore Medical Center
• Debra S. Copit, MD, Albert Einstein Medical Center
• Ann L. Honebrink, MD, Penn Health at Radnor
• Isabel I. Law, RN, South Carolina Comprehensive Breast Center
• Judith Macon, RN, MA, Suburban Hospital Cancer Program
• Suzanne McGettigan Bensman, MSN, CRNP, AOCN
• Lisa McGinty, RN, BSN, Abramson Cancer Center, University of Pennsylvania
• Maria Rocktashel, MSN, CRNP, Delaware Valley Surgical Associates
• Lynn M. Schuchter, MD, University of Pennsylvania Abramson Cancer Center
• Michele D. Stolper, Dana-Farber Cancer Institute
• Fionda N. Williams, RN, BSN, Baltimore City Cancer Program

Glossary

idiopathic

Describes a disease of unknown cause.

IHC

Immunohistochemistry. A laboratory test that uses antibodies to detect particular proteins or receptors in cells or tissue samples. IHC tests may be used to help determine whether breast cancer cells have hormone receptors or too much of the HER2/neu protein. Results from IHC can help determine breast cancer treatment options.

IL-1

interleukin-1. A type of biological response modifier that stimulates immune system cells that fight disease, and is involved in inflammatory responses. There are two forms of IL-1, IL-1 alfa and IL-1 beta. Both forms of IL-1 are produced by the body, and can also be made in the laboratory.

IL-1-alfa

Interleukin-1-alfa. A type of biological response modifier (a substance that can improve the body's response to infection and disease). IL-1-alfa stimulates the growth and action of immune system cells that fight disease. IL-1-alfa is normally produced by the body, but it can also be made in the laboratory. Also called IL-1-alpha.

IL-11

Interleukin-11. A type of biological response modifier (a substance that can improve the body's natural response to disease) that stimulates immune response and may reduce toxicity to the gastrointestinal system resulting from cancer therapy. These substances are normally produced by the body. They are also made in the laboratory for use in treating cancer and other diseases. Also called oprelvekin.

IL-12

Interleukin-12. A type of biological response modifier (a substance that can improve the body's natural response to disease) that enhances the ability of the immune system to kill tumor cells and may interfere with blood flow to the tumor. These substances are normally produced by the body. They are also made in the laboratory for use in treating cancer and other diseases.

IL-2

Interleukin-2. A type of biological response modifier (a substance that can improve the body's natural response to disease) that enhances the ability of the immune system to kill tumor cells and may interfere with blood flow to the tumor. These substances are normally produced by the body. Aldesleukin is IL-2 that is made in the laboratory for use in treating cancer and other diseases.

IL-3

Interleukin-3. A type of biological response modifier (a substance that can improve the body's natural response to disease) that enhances the immune system's ability to fight tumor cells. These substances are normally produced by the body. They are also made in the laboratory for use in treating cancer and other diseases.

IL-4

Interleukin-4. A type of biological response modifier (a substance that can improve the body's natural response to disease) that enhances the immune system's ability to fight tumor cells. These substances are normally produced by the body. They are also made in the laboratory for use in treating cancer and other diseases.

IL-6

Interleukin-6. A type of biological response modifier (a substance that can improve the body's natural response to infection and disease). These substances are normally produced by the body, but they can also be made in the laboratory.

IM

Intramuscular. Within or into muscle.

imagery

A technique in which the person focuses on positive images in his or her mind. Some people use imagery to help manage side effects of breast cancer treatment.

imaging

Tests that produce pictures of areas inside the body.

imaging procedure

A method of producing pictures of areas inside the body.

immune adjuvant

A drug that stimulates the immune system to respond to disease.

immune function

Production and action of cells that fight disease or infection.

immune response

The activity of the immune system against foreign substances (antigens).

immune system

Pronunciation: (im-YOON)

The complex group of organs and cells that defends the body against infections and other diseases.

immune system tolerance

The failure of the immune system to respond to an antigen that previously caused an immune response.

immunization

A technique used to cause an immune response that results in resistance to a specific disease, especially an infectious disease.

immunoassay

A test that uses the binding of antibodies to antigens to identify and measure certain substances. Immunoassays may be used to diagnose disease. Also, test results can provide information about a disease that may help in planning treatment (for example, when estrogen receptors are measured in breast cancer).

immunocompetence

The ability to produce a normal immune response.

immunocompetent

Having the ability to produce a normal immune response.

immunocompromised

Having a weakened immune system caused by certain diseases or treatments.

immunodeficiency

The decreased ability of the body to fight infection and disease.

immunodeficiency syndrome

The inability of the body to produce an immune response.

immunoglobulin

A protein that acts as an antibody.

immunohistochemistry

IHC. A laboratory test that uses antibodies to detect particular proteins or receptors in cells or tissue samples. IHC tests may be used to help determine whether breast cancer cells have hormone receptors or too much of the HER2/neu protein. Results from IHC can help determine breast cancer treatment options.

immunological adjuvant

A substance used to help boost the immune response to a vaccine so that less vaccine is needed.

immunology

The study of the body's immune system.

immunomodulation

Change in the body's immune system, caused by agents that activate or suppress its function.

immunoscintigraphy

An imaging procedure in which antibodies labeled with radioactive substances are given to the person. A picture is taken of sites in the body where the antibody localizes.

immunostimulant

A substance that increases the ability of the immune system to fight infection and disease.

immunosuppression

Suppression of the body's immune system and its ability to fight infections or disease. Immunosuppression may be deliberately induced with medications, as in preparation for bone marrow or other organ transplantation to prevent rejection of the donor tissue. It may also result from certain diseases such as AIDS or lymphoma or from anticancer medications.

immunosuppressive

Describes the ability to lower immune system responses.

immunosuppressive therapy

Therapy used to decrease the body's immune response, such as medications given to prevent transplant rejection.

immunotherapy

Pronunciation: (IH-myoo-noh-THAYR-uh-pee)

Treatment to stimulate or restore the ability of the immune system to fight breast cancer, infections, and other diseases. Also used to lessen certain side effects that may be caused by breast cancer treatment. Also called biological therapy, biotherapy, or biological response modifier (BRM) therapy.

immunotoxin

An antibody linked to a toxic substance. Some immunotoxins can bind to breast cancer cells and kill them.

implant

A substance or object that is put in the body as a prosthesis, or for treatment or diagnosis. Some women who have mastectomies choose to get a breast implant during reconstructive surgery.

implant radiation

Pronunciation: (ray-dee-AY-shun)

A procedure in which radioactive material sealed in needles, seeds, wires, or catheters is placed directly into or near a breast tumor. Also called brachytherapy, internal radiation, or interstitial radiation.

implantable pump

A small device installed under the skin to administer a steady dose of medication.

in situ cancer

Early breast cancer that has not spread to neighboring tissue.

in vitro

In the laboratory (outside the body). The opposite of in vivo (in the body).

in vivo

In the body. The opposite of in vitro (outside the body or in the laboratory).

incidence

The number of new cases of breast cancer diagnosed each year.

incision

Pronunciation: (in-SIH-zhun)

A cut made in the body to perform surgery.

incisional biopsy

Pronunciation: (in-SIH-zhun-al BY-op-see)

A surgical procedure in which a portion of a breast lump or suspicious area is removed for diagnosis. The tissue is then examined under a microscope.

incontinence

Pronunciation: (in-KAHN-tih-nens)

Inability to control the flow of urine from the bladder (urinary incontinence) or the escape of stool from the rectum (fecal incontinence).

incubated

Grown in the laboratory under controlled conditions. (For instance, white blood cells can be grown in special conditions so that they attack specific cancer cells when returned to the body.)

Indian cress

Nasturtium officinale. Parts of the flowering plant have been used in some cultures to treat certain medical problems. It may have anticancer effects. Also called watercress.

Indian elm

Ulmus fulva or Ulmus rubra. The inner bark of this plant has been used in some cultures to treat certain medical problems. It may have antioxidant effects. Also called slippery elm, gray elm, red elm, and sweet elm.

Indian rhubarb

Rheum palmatum or Rheum officinale. The root of this plant has been used in some cultures to treat certain medical problems. It may have anti-inflammatory and anticancer effects. Also called rhubarb, da-huang, Chinese rhubarb, and Turkish rhubarb.

Indian valerian

Valeriana officinalis. A plant whose roots are used as a sedative and to treat certain medical conditions. It is being studied as a way to improve sleep in cancer patients undergoing treatment. Also called valerian, garden valerian, Pacific valerian, Mexican valerian, garden heliotrope, and Valerianae radix.

indication

In medicine, a sign, symptom, or medical condition that leads to the recommendation of a treatment, test, or procedure.

indolent

Pronunciation: (IN-doe-lint)

A type of breast cancer that grows slowly.

induction therapy

Treatment designed to be used as a first step toward shrinking the breast cancer and in evaluating response to medications and other agents. Induction therapy is followed by additional therapy to eliminate whatever breast cancer remains.

infection

Invasion and multiplication of germs in the body. Infections can occur in any part of the body and can spread throughout the body. The germs may be bacteria, viruses, yeast, or fungi. They can cause a fever and other problems, depending on where the infection occurs. When the body's natural defense system is strong, it can often fight the germs and prevent infection. Some breast cancer treatments can weaken the natural defense system.

infertile

Unable to produce children.

infertility

The inability to produce children.

infiltrating cancer

Breast cancer that has spread beyond the layer of tissue in which it developed and is growing into surrounding, healthy tissues. Also called invasive cancer.

infiltrating ductal carcinoma

The most common type of invasive breast cancer. It starts in the cells that line the milk ducts in the breast, grows outside the ducts, and often spreads to the lymph nodes.

inflammation

Pronunciation: (in-fla-MAY-shun)

Redness, swelling, pain, and/or a feeling of heat in an area of the body. This is a protective reaction to injury, disease, or irritation of the tissues.

inflammatory

Having to do with inflammation (redness, swelling, pain, and a feeling of heat that helps protect tissues affected by injury or disease).

inflammatory breast cancer

A type of breast cancer in which the breast looks red and swollen and feels warm. The skin of the breast may also show the pitted appearance called peau d'orange (like the skin of an orange). The redness and warmth occur because the cancer cells block the lymph vessels in the skin.

informed consent

A process in which a person learns key facts about a clinical trial, including potential risks and benefits, before deciding whether or not to participate in a study. Informed consent continues throughout the trial.

infraclavicular nodes

Lymph nodes located beneath the collar bone.

infusion

A method of putting fluids, including medications, into the bloodstream. Also called intravenous infusion.

ingestion

Taking into the body by mouth.

inhalation

In medicine, refers to the act of taking a substance into the body by breathing.

inherited

Transmitted through genes that have been passed from parents to their offspring (children). Breast cancer genes are inherited.

injection

Use of a syringe and needle to push fluids or medicationsinto the body; often called a "shot."

inoperable

Describes a breast cancer that cannot be treated by surgery.

insomnia

Difficulty in going to sleep or getting enough sleep. Insomnia is a potential side effect of some breast cancer treatments.

instillation

In medicine, a method used to put a liquid into the body slowly or drop by drop.

Institutional Review Board

IRB. A group of scientists, doctors, clergy, and consumers at each healthcare facility that participates in a clinical trial. IRBs are designed to protect study participants. They review and must approve the action plan for every clinical trial. They check to see that the trial is well designed, does not involve undue risks, and includes safeguards for participants.

intensity-modulated radiation therapy

IMRT. A type of 3-dimensional breast cancer radiation therapy that uses computer-generated images to show the size and shape of the tumor. Thin beams of radiation of different intensities are aimed at the tumor from many angles. This type of radiation therapy reduces the damage to healthy tissue near the tumor.

intercalator

In biochemistry, a type of molecule that binds to DNA and inserts itself into the DNA structure. Some intercalators are used as treatments for breast cancer.

interferon

Pronunciation: (in-ter-FEER-on)

A biological response modifier (a substance that can improve the body's natural response to infections and other diseases). Interferons interfere with the division of breast cancer cells and can slow tumor growth. There are several types of interferons, including interferon-alpha, -beta, and -gamma. The body normally produces these substances. They are also made in the laboratory to treat breast cancer and other diseases.

interleukin

Pronunciation: (in-ter-LOO-kin)

A biological response modifier (substance that can improve the body's natural response to infection and disease) that helps the immune system fight infection and breast cancer. These substances are normally produced by the body. They are also made in the laboratory for use in treating cancer and other diseases.

interleukin-1

IL-1. A type of biological response modifier that stimulates immune system cells that fight disease, and is involved in inflammatory responses. There are two forms of IL-1, IL-1 alfa and IL-1 beta. Both forms of IL-1 are produced by the body, and can also be made in the laboratory.

interleukin-1-alpha

IL-1-alpha. A type of biological response modifier (a substance that can improve the body's natural response to infection and disease). IL-1-alpha stimulates the growth and action of immune system cells that fight disease. IL-1-alpha is normally produced by the body, but it can also be made in the laboratory. Also called IL-1-alfa.

interleukin-11

Pronunciation: (in-ter-LOO-kin)

IL-11. A type of biological response modifier (a substance that can improve the body's natural response to infection and disease) that stimulates immune response and may reduce toxicity to the gastrointestinal system resulting from cancer therapy. These substances are normally produced by the body. They are also made in the laboratory for use in treating cancer and other diseases. Also called oprelvekin.

interleukin-12

Pronunciation: (in-ter-LOO-kin)

IL-12. A type of biological response modifier (a substance that can improve the body's natural response to infection and disease) that enhances the ability of the immune system to kill tumor cells and may interfere with blood flow to the tumor. These substances are normally produced by the body. They are also made in the laboratory for use in treating cancer and other diseases.

interleukin-2

Pronunciation: (in-ter-LOO-kin)

IL-2. A type of biological response modifier (a substance that can improve the body's natural response to infection and disease) that stimulates the growth of certain disease-fighting blood cells in the immune system. These substances are normally produced by the body. Aldesleukin is IL-2 that is made in the laboratory for use in treating cancer and other diseases.

interleukin-3

Pronunciation: (in-ter-LOO-kin)

IL-3. A type of biological response modifier (a substance that can improve the body's natural response to infection and disease) that enhances the immune system's ability to fight tumor cells. These substances are normally produced by the body. They are also made in the laboratory for use in treating cancer and other diseases.

interleukin-4

Pronunciation: (in-ter-LOO-kin)

IL-4. A type of biological response modifier (a substance that can improve the body's natural response to infection and disease) that enhances the immune system's ability to fight tumor cells. These substances are normally produced by the body. They are also made in the laboratory for use in treating cancer and other diseases.

interleukin-6

Pronunciation: (in-ter-LOO-kin)

IL-6. A type of biological response modifier (a substance that can improve the body's natural response to infection and disease). These substances are normally produced by the body, but they can also be made in the laboratory for use in treating cancer and other diseases.

interleukin-7

Pronunciation: (in-ter-LOO-kin)

IL-7. A type of biological response modifier (a substance that can improve the body's natural response to infection and disease) that enhances the immune system's ability to fight tumor cells. IL-7 is made by cells in the bone marrow, and can stimulate T cells and B cells to grow. IL-7 can also be made in the laboratory for use in treating cancer and other diseases.

internal radiation

Pronunciation: (ray-dee-AY-shun)

A procedure in which radioactive material sealed in needles, seeds, wires, or catheters is placed directly into or near a breast tumor. Also called brachytherapy, implant radiation, or interstitial radiation therapy.

interstitial radiation therapy

A procedure in which radioactive material sealed in needles, seeds, wires, or catheters is placed directly into or near a breast tumor. Also called brachytherapy, internal radiation, or implant radiation.

intervention group

The group receiving the study agent that is being tested in a clinical trial or clinical study.

intestinal

Having to do with the intestines.

intestinal villi

Tiny hair-like projections that line the inside of the small intestine. They contain blood vessels and help absorb nutrients.

intestine

Pronunciation: (in-TES-tin)

The long, tube-shaped organ in the abdomen that completes the process of digestion. There is both a large intestine and a small intestine. Also called the bowel.

intracarotid infusion

The introduction of fluids and medicationsdirectly into the carotid artery, the main artery in the neck that carries blood from the heart to the brain.

intracavitary

Pronunciation: (IN-truh-KA-vuh-tayr-ee)

Within a cavity or space, such as the abdomen, pelvis, pleura, or chest.

intracavitary radiation

Pronunciation: (IN-truh-KA-vuh-tayr-ee ray-dee-AY-shun)

A procedure in which a radioactive source (implant) is placed in a body cavity such as the chest cavity or the vagina.

intracellular

Inside a cell.

intradermal

Within the dermis, which is the layer of skin below the epidermis (outermost layer).

intraductal carcinoma

Pronunciation: (in-tra-DUK-tal KAR-si-NO-ma)

A noninvasive, early breast cancer 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, intraductal carcinoma 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 ductal carcinoma in situ (DCIS).

intraductal papilloma

Pronunciation: (IN-truh-DUK-tul PA-pih-LOH-muh)

A benign (noncancerous), wart-like growth in a milk duct of the breast. It is usually found close to the nipple and may cause a clear, sticky, or bloody discharge from the nipple. It may also cause pain and a lump in the breast that can be felt or seen. It usually affects women aged 35-55 years. Having an intraductal papilloma does not increase the risk of developing breast cancer.

intraepithelial

Pronunciation: (in-tra-eh-pih-THEEL-ee-ul)

Within the layer of cells that form the surface or lining of an organ.

intrahepatic

Pronunciation: (in-tra-hep-AT-ik)

Within the liver.

intrahepatic bile duct

A bile duct that passes through and drains bile from the liver.

intrahepatic infusion

The delivery of anticancer medications directly to the blood vessels of the liver.

intralesional

Within a cancerous area, for example, within a tumor in the skin.

intramuscular

IM. Within or into muscle.

intramuscular injection

Injection into muscle.

intraoperative radiation therapy

IORT. Radiation treatment aimed directly at a breast tumor during surgery.

intraperitoneal

Pronunciation: (IN-truh-PAYR-ih-toh-NEE-ul)

IP. Within the peritoneal cavity (the area that contains the abdominal organs).

intraperitoneal chemotherapy

Pronunciation: (IN-truh-PAYR-ih-toh-NEE-ul kee-moh-THAYR-uh-pee)

Treatment in which anticancer medications are put directly into the abdominal cavity through a thin tube.

intraperitoneal infusion

A method of delivering fluids and medications directly into the abdominal cavity through a thin tube. Also called peritoneal infusion.

intraperitoneal radiation therapy

Pronunciation: (IN-truh-PAYR-ih-toh-NEE-ul ray-dee-AY-shun)

Treatment in which a radioactive liquid is put directly into the abdomen through a thin tube.

intrapleural

Within the pleural cavity.

intratumoral

Within a tumor.

intravenous

Pronunciation: (in-tra-VEE-nus)

IV. Within a blood vessel (vein).

intravenous injection

IV. Injection into a vein.

invasive cancer

Breast cancer that has spread beyond the layer of tissue in which it developed and is growing into surrounding, healthy tissues. Also called infiltrating cancer.

invasive ductal cancer

Breast cancer that began in the ducts of the breast and is growing into surrounding, healthy tissue. Also called infiltrating ductal cancer.

invasive lobular cancer

Breast cancer that began in the lobules of the breast and is growing into surrounding, healthy tissue. Also called infiltrating lobular cancer.

invasive procedure

A medical procedure that invades (enters) the body, usually by cutting or puncturing the skin or by inserting instruments into the body.

investigational

In clinical trials, refers to a medication (including a new medicine, dose, combination, or route of administration) or procedure that has undergone basic laboratory testing and received approval from the US Food and Drug Administration (FDA) to be tested in human beings. A medicine or procedure may be approved by the FDA for use in one disease or condition, but be considered investigational in other diseases or conditions. Also called experimental.

investigator

A researcher in a clinical trial or clinical study.

inviable

Not able to survive.

ionizing radiation

Pronunciation: (I-uh-NIZE-ing ray-dee-AY-shun)

A type of radiation made (or given off) by x-ray procedures, radioactive substances, rays that enter the earth's atmosphere from outer space, and other sources. At high doses ionizing radiation increases chemical activity inside cells and can lead to health risks, including breast cancer.

IORT

Intraoperative radiation therapy. Radiation treatment aimed directly at a breast tumor during surgery.

IP

Intraperitoneal. Within the peritoneal cavity (the area that contains the abdominal organs).

ipsilateral

Having to do with the same side of the body; for example, having cancer in the same breast.

IRB

Institutional Review Board. A group of scientists, doctors, clergy, and consumers at each healthcare facility that participates in a clinical trial. IRBs are designed to protect study participants. They review and must approve the action plan for every clinical trial. They check to see that the trial is well designed, does not involve undue risks, and includes safeguards for participants.

irradiated

Treated with radiation.

irradiation

Pronunciation: (ih-RAY-dee-AY-shun)

The use of high-energy radiation from x-rays, gamma rays, neutrons, and other sources to kill breast cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy) or from materials called radioisotopes. Radioisotopes produce radiation and can be placed in or near the tumor or in the area near cancer cells. This type of radiation treatment is called internal radiation therapy, implant radiation, interstitial radiation, or brachytherapy. Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that circulates throughout the body. Irradiation is also called radiation therapy, radiotherapy, and x-ray therapy.

irreversible toxicity

Side effects that are caused by toxic substances or something harmful to the body and do not go away.

isoflavone

An estrogen-like substance made by some plants, including the soy plant. Soy isoflavones are being studied in the prevention of breast cancer, hot flashes that occur with menopause, and osteoporosis (loss of bone density).

isointense

Having the same intensity as another object. Used to describe the results of imaging tests, such as x-rays, MRIs, or CT scans.

isomer

One of two or more compounds that have the same chemical formula but different arrangements of the atoms within the molecules and that may have different physical/chemical properties.

isthmus

Pronunciation: (iz-muhs)

A narrow part inside the body that connects two larger structures.

IU

International unit. A unit of measurement based on the International System of Units. This system defines units to measure length, time, mass, electric current, temperature, light intensity, and the amount of a substance. It can be used to express measurements of fat-soluble vitamins and some hormones, enzymes, and medications.

IV

Intravenous (in-tra-VEE-nus). Injected into a blood vessel (vein).

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