National Cancer Institute National Cancer Institute
U.S. National Institutes of Health National Cancer Institute
NCI Home Cancer Topics Clinical Trials Cancer Statistics Research & Funding News About NCI
Dictionary of Cancer Terms
In EnglishEn español
Page Options
Print This Page  Print This Page
Quick Links
Director's Corner
Updates from the Director

Dictionary of Cancer Terms
Cancer-related terms

NCI Drug Dictionary
Definitions, names, and links

Funding Opportunities
Research and training

NCI Publications
Order/download free booklets

Advisory Boards and Groups
Information, meetings, reports

Science Serving People
Learn more about NCI

Español
Información en español
NCI Highlights
Virtual and Standard Colonoscopy Both Accurate

NCI Responds to Hurricanes

The Nation's Investment in Cancer Research FY 2009

Cancer Trends Progress Report: 2007 Update

Past Highlights
You CAN Quit Smoking Now!
Search for
# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

282 results found for:   
  I



I.V.  
Into or within a vein. I.V. usually refers to a way of giving a drug or other substance through a needle or tube inserted into a vein. Also called intravenous.

ibandronate  
A drug that is used to prevent and treat osteoporosis, and is being studied in the treatment of cancer that has spread to the bones. It belongs to the family of drugs called bisphosphonates.

IBMFS  
Inherited bone marrow failure syndrome. A rare disorder in which a person’s bone marrow is unable to make enough blood cells and there is a family history of the same disorder. There are several different inherited bone marrow failure syndromes. Patients with an IBMFS are at high risk of forming acute leukemia or certain solid tumors. Also called inherited bone marrow failure syndrome.

ibritumomab tiuxetan  (ih-brih-TOO-moh-mab ty-oo-EKS-eh-tan)
A monoclonal antibody that is used to treat certain types of B-cell non-Hodgkin lymphoma and is being studied in the treatment and detection of other types of B-cell tumors. Monoclonal antibodies are made in the laboratory and can locate and bind to substances in the body, including cancer cells. Ibritumomab binds to the protein called CD20, which is found on B cells. It is linked to the compound tiuxetan. This allows certain radioisotopes to be attached before it is given to a patient. It is a type of monoclonal antibody-chelator conjugate. Also called Zevalin.

ibuprofen  (I-byoo-PROH-fen)
A drug used to treat fever, swelling, pain, and redness by preventing the body from making a substance that causes inflammation. It is a type of nonsteroidal anti-inflammatory drug (NSAID). Also called Motrin and Advil.

ICD  
A small device used to correct a heartbeat that is abnormal (too fast, too slow, or irregular). The device is placed by surgery in the chest or abdomen. Wires are passed through a vein to connect the device to the heart. When it detects abnormal heartbeats, it sends an electrical shock to the heart to restore the heartbeat to normal. Also called implantable cardioverter-defibrillator.

ICI 182780  
A drug used to treat certain types of breast cancer in postmenopausal women. It is also being studied in the treatment of other types of cancer. ICI 182780 blocks estrogen activity in the body and is a type of antiestrogen. Also called fulvestrant and Faslodex.

ICI D1694  
An anticancer drug that stops tumor cells from growing by blocking the ability of cells to make DNA. It belongs to the family of drugs called thymidylate synthase inhibitors. Also called raltitrexed.

idarubicin  (I-duh-ROO-bih-sin)
An anticancer drug that is a type of antitumor antibiotic. Also called 4-demethoxydaunorubicin.

IDEC-Y2B8  
A radiolabeled monoclonal antibody that is used to treat certain types of B-cell non-Hodgkin lymphoma and is being studied in the treatment of other types of B-cell tumors. It is made up of the monoclonal antibody ibritumomab plus the radioisotope yttrium Y 90. It binds to the protein called CD20, which is found on B cells. The radiation in the yttrium Y 90 may kill the cancer cells. IDEC-Y2B8 is a type of radiopharmaceutical. Also called yttrium Y 90 ibritumomab tiuxetan, Y 90 ibritumomab tiuxetan, and Y 90 Zevalin.

idiopathic  
Describes a disease of unknown cause.

idiopathic myelofibrosis  (IH-dee-oh-PA-thik MY-eh-loh-fy-BROH-sis)
A progressive, chronic disease in which the bone marrow is replaced by fibrous tissue and blood is made in organs such as the liver and the spleen, instead of in the bone marrow. This disease is marked by an enlarged spleen and progressive anemia. Also called chronic idiopathic myelofibrosis, agnogenic myeloid metaplasia, primary myelofibrosis, and myelosclerosis with myeloid metaplasia.

idiopathic pneumonia syndrome  (IH-dee-oh-PA-thik noo-MOH-nyuh SIN-drome)
A set of pneumonia-like symptoms (such as fever, chills, coughing, and breathing problems) that occur with no sign of infection in the lung. Idiopathic pneumonia syndrome is a serious condition that can occur after a stem cell transplant.

idiopathic thrombocytopenic purpura  (IH-dee-oh-PA-thik THROM-boh-sy-toh-PEE-nik PUR-pyuh-ruh)
A condition in which platelets (blood cells that cause blood clots to form) are destroyed by the immune system. The low platelet count causes easy bruising and bleeding, which may be seen as purple areas in the skin, mucous membranes, and outer linings of organs. Also called immune thrombocytopenic purpura and ITP.

idoxifene  
A drug that blocks the effects of estrogen.

idoxuridine  
A drug that reduces the risk of cancer cell growth by interfering with the cells' DNA.

iFOBT  
Immunoassay fecal occult blood test. A test to check for blood in the stool. A brush is used to collect water drops from around the surface of a stool while it is still in the toilet bowl. The samples are then sent to a laboratory, where they are checked for a human blood protein. Blood in the stool may be a sign of colorectal cancer. Also called immunochemical fecal occult blood test, immunologic fecal occult blood test, and immunoassay fecal occult blood test.

ifosfamide  
An anticancer drug that belongs to the family of drugs called alkylating agents.

IgG-RFT5-dgA  
A monoclonal antibody linked to a toxic substance. It is being studied in the treatment of melanoma that has spread to distant parts of the body. IgG-RFT5-dgA is made in the laboratory. It can find and kill certain white blood cells that prevent the immune system from killing cancer cells. Also called RFT5-dgA immunotoxin.

IH636 grape seed extract  
A substance being studied for its ability to prevent damage to normal tissue caused by radiation therapy. It is a type of antioxidant.

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. Also called interleukin-1.

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 interleukin-1-alfa, interleukin-1-alpha, and IL-1-alpha.

IL-1-alpha  
Interleukin-1-alpha. A type of biological response modifier (a substance that can improve the body's 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 interleukin-1-alpha, interleukin-1-alfa, and IL-1-alfa.

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 interleukin-11 and 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. Also called interleukin-12.

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. Also called interleukin-3.

IL-4  
One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body. IL-4 is made by a type of T cell (white blood cell that attacks virus-infected cells, foreign cells, and cancer cells). It causes B lymphocytes to increase and to make antibodies and also increases the production of T cells. IL-4 made in the laboratory is being used as a biological response modifier to boost the immune system in cancer therapy. IL-4 is a type of cytokine. Also called interleukin-4.

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. Also called interleukin-6.

IL-7  
Interleukin-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. Also called interleukin-7.

ileostomy  (IL-ee-OS-toh-mee)
An opening into the ileum, part of the small intestine, from the outside of the body. An ileostomy provides a new path for waste material to leave the body after part of the intestine has been removed.

ileus  (IH-lee-us)
Blockage of the intestines

iloprost  
A substance that is being studied in the prevention of lung cancer. It belongs to the family of drugs called prostaglandin analogs.

ILX-295501  
A substance that is being studied as an anticancer drug. It belongs to the family of drugs called diarylsulfonylureas.

ILX23-7553  
A substance that is being studied as an anticancer drug.

IM  
Intramuscular. Within or into muscle. Also called intramuscular.

IM-862  
An anticancer drug that belongs to the family of drugs called angiogenesis inhibitors.

imagery  (IH-mij-ree)
A technique in which the person focuses on positive images in his or her mind.

imaging  (IH-muh-jing)
In medicine, a process that makes pictures of areas inside the body. Imaging uses methods such as x-rays (high-energy radiation), ultrasound (high-energy sound waves), and radio waves.

imaging procedure  
A method of producing pictures of areas inside the body.

imatinib mesylate  (ih-MAH-tih-nib MEH-zih-layt)
A drug used to treat different types of leukemia and other cancers of the blood, gastrointestinal stromal tumors, skin tumors called dermatofibrosarcoma protuberans, and a rare condition called systemic mastocytosis. It is also being studied in the treatment of other types of cancer. Imatinib mesylate blocks the protein made by the bcr/abl oncogene. It is a type of tyrosine kinase inhibitor. Also called Gleevec and STI571.

imexon  (i-MEX-on)
A substance that is being studied in the treatment of some types of cancer, including pancreatic, lung, breast, prostate, melanoma, and multiple myeloma. It belongs to the family of drugs called cyanoaziridine derivatives. Also called Amplimexon.

imipenem  
An antibiotic drug used to treat severe or very resistant infection. It belongs to the family of drugs called carbapenems.

imiquimod  (ih-MIH-kwee-mod)
A drug used to treat early basal cell skin cancer and certain other skin conditions. It is being studied in the treatment of other types of cancer. Imiquimod is a type of biological response modifier. Also called Aldara.

immature teratoma  (IH-muh-CHOOR TAYR-uh-TOH-muh)
A rare type of malignant (cancer) germ cell tumor (type of tumor that begins in the cells that give rise to sperm or eggs) that often contains several different types of tissue such as hair, muscle, and bone.

IMMU-106  
A monoclonal antibody that is being studied in the treatment of refractory B-cell non-Hodgkin lymphoma. Monoclonal antibodies are made in the laboratory and can locate and bind to substances in the body, including cancer cells. IMMU-106 binds to the protein CD20, which is found on B cells (a type of immune system cell), and some types of lymphoma cells. Also called hA20 and HCD20.

immune adjuvant  (ih-MYOON A-juh-vunt)
A drug that stimulates the immune system to respond to disease.

immune complex hemolytic anemia  (ih-MYOON KOM-plex HEE-moh-LIH-tik uh-NEE-mee-uh)
A condition in which the body’s immune system stops red blood cells from forming or causes them to clump together. Immune complex hemolytic anemia can occur in patients who have chronic lymphocytic leukemia (CLL). Also called autoimmune hemolytic anemia and immunohemolytic anemia.

immune function  (ih-MYOON FUNK-shun)
Production and action of cells that fight disease or infection.

immune response  (ih-MYOON reh-SPONTS)
The activity of the immune system against foreign substances (antigens).

immune system  (ih-MYOON SIS-tem)
The complex group of organs and cells that defends the body against infections and other diseases.

immune system tolerance  (ih-MYOON SIS-tem TAH-leh-runts)
The failure of the immune system to respond to an antigen that previously caused an immune response.

immune thrombocytopenic purpura  (ih-MYOON THROM-boh-sy-toh-PEE-nik PUR-pyuh-ruh)
A condition in which platelets (blood cells that cause blood clots to form) are destroyed by the immune system. The low platelet count causes easy bruising and bleeding, which may be seen as purple areas in the skin, mucous membranes, and outer linings of organs. Also called idiopathic thrombocytopenic purpura and ITP.

immunity  (ih-MYOO-nih-tee)
The condition of being protected against an infectious disease. Immunity can be caused by a vaccine, previous infection with the same agent, or by transfer of immune substances from another person or animal.

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).

immunoassay fecal occult blood test  (IH-myoo-noh-A-say FEE-kul uh-KULT ...)
iFOBT. A test to check for blood in the stool. A brush is used to collect water drops from around the surface of a stool while it is still in the toilet bowl. The samples are then sent to a laboratory, where they are checked for a human blood protein. Blood in the stool may be a sign of colorectal cancer. Also called iFOBT, immunochemical fecal occult blood test, and immunologic fecal occult blood test.

immunochemical fecal occult blood test  (IH-myoo-noh-KEH-mih-kul FEE-kul uh-KULT...)
iFOBT. A test to check for blood in the stool. A brush is used to collect water drops from around the surface of a stool while it is still in the toilet bowl. The samples are then sent to a laboratory, where they are checked for a human blood protein. Blood in the stool may be a sign of colorectal cancer. Also called iFOBT, immunologic fecal occult blood test, and immunoassay fecal occult blood test.

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  (IH-myoo-noh-dih-FIH-shun-see)
The decreased ability of the body to fight infections and other diseases.

immunodeficiency syndrome  (IH-myoo-noh-dih-FIH-shun-see SIN-drome)
The inability of the body to produce an immune response.

immunoglobulin  
A protein that acts as an antibody.

immunohemolytic anemia  (IH-myoo-noh-HEE-moh-LIH-tik uh-NEE-mee-uh)
A condition in which the body’s immune system stops red blood cells from forming or causes them to clump together. Immunohemolytic anemia can occur in patients who have chronic lymphocytic leukemia (CLL). Also called immune complex hemolytic anemia and autoimmune hemolytic anemia.

immunologic fecal occult blood test  (IH-myoo-noh-LAH-jik FEE-kul uh-KULT...)
iFOBT. A test to check for blood in the stool. A brush is used to collect water drops from around the surface of a stool while it is still in the toilet bowl. The samples are then sent to a laboratory, where they are checked for a human blood protein. Blood in the stool may be a sign of colorectal cancer. Also called iFOBT, immunochemical fecal occult blood test, and immunoassay fecal occult blood test.

immunological adjuvant  (IH-myoo-noh-LAH-jih-kul A-juh-vunt)
A substance used to help boost the immune response to a vaccine so that less vaccine is needed.

immunology  (IH-myoo-NAH-loh-jee)
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.

immunophenotyping  (IM-yoo-no-FEE-no-tie-ping)
A process used to identify cells, based on the types of antigens or markers on the surface of the cell. This process is used to diagnose specific types of leukemia and lymphoma by comparing the cancer cells to normal cells of the immune system.

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  (IH-myoo-noh-suh-PREH-shun)
Suppression of the body's immune system and its ability to fight infections and other diseases. Immunosuppression may be deliberately induced with drugs, 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 drugs.

immunosuppressive  (IH-myoo-noh-suh-PREH-siv)
Describes the ability to decrease the body's immune system responses.

immunosuppressive therapy  (IH-myoo-noh-suh-PREH-siv THAYR-uh-pee)
Therapy used to decrease the body's immune responses, such as drugs given to prevent transplant rejection.

immunotherapy  (IH-myoo-noh-THAYR-uh-pee)
Treatment to boost or restore the ability of the immune system to fight cancer, infections, and other diseases. Also used to lessen certain side effects that may be caused by some cancer treatments. Agents used in immunotherapy include monoclonal antibodies, growth factors, and vaccines. These agents may also have a direct antitumor effect. Also called biological therapy, biotherapy, biological response modifier therapy, and BRM therapy.

immunotoxin  (IH-myoo-noh-TOK-sin)
An antibody linked to a toxic substance. Some immunotoxins can bind to cancer cells and kill them.

Imodium  (ih-MOH-dee-um)
A drug used to treat diarrhea. Imodium slows the movement of the muscles in the small intestine to allow more water to be taken out of the feces (waste matter) and more nutrients to be absorbed. Also called loperamide hydrochloride.

impairment  (im-PAYR-ment)
A loss of part or all of a physical or mental ability, such as the ability to see, walk, or learn.

implant  
A substance or object that is put in the body as a prosthesis, or for treatment or diagnosis.

implant radiation therapy  (... RAY-dee-AY-shun THAYR-uh-pee)
A type of radiation therapy in which radioactive material sealed in needles, seeds, wires, or catheters is placed directly into or near a tumor. Also called brachytherapy, radiation brachytherapy, and internal radiation therapy.

implantable cardioverter-defibrillator  (im-PLAN-tuh-bul KAR-dee-oh-VER-ter-dee-FIH-brih-LAY-ter)
A small device used to correct a heartbeat that is abnormal (too fast, too slow, or irregular). The device is placed by surgery in the chest or abdomen. Wires are passed through a vein to connect the device to the heart. When it detects abnormal heartbeats, it sends an electrical shock to the heart to restore the heartbeat to normal. Also called ICD.

implantable pump  
A small device installed under the skin to administer a steady dose of drugs.

impotence  
In medicine, refers to the inability to have an erection of the penis adequate for sexual intercourse. Also called erectile dysfunction.

impotent  (IM-po-tent)
In medicine, describes the inability to have an erection of the penis adequate for sexual intercourse.

IMRT  
Intensity-modulated radiation therapy. A type of 3-dimensional 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. Also called intensity-modulated radiation therapy.

In 111 ibritumomab tiuxetan  (... ih-brih-TOO-moh-mab ty-oo-EKS-eh-tan)
A radiolabeled monoclonal antibody that is used to detect certain types of B-cell non-Hodgkin lymphoma and is being studied in the detection of other types of B-cell tumors. It is made up of the monoclonal antibody ibritumomab plus the radioisotope indium 111. It binds to the protein called CD20, which is found on B cells. A machine is used to detect which cells in the body have bound the antibody. In 111 ibritumomab tiuxetan is a type of radiopharmaceutical. Also called indium In 111 ibritumomab tiuxetan and In 111 Zevalin.

In 111 Zevalin  (... ZEV-uh-lin)
A radiolabeled monoclonal antibody that is used to detect certain types of B-cell non-Hodgkin lymphoma and is being studied in the detection of other types of B-cell tumors. It is made up of the monoclonal antibody ibritumomab plus the radioisotope indium 111. It binds to the protein called CD20, which is found on B cells. A machine is used to detect which cells in the body have bound the antibody. In 111 Zevalin is a type of radiopharmaceutical. Also called indium In 111 ibritumomab tiuxetan and In 111 ibritumomab tiuxetan.

in vitro  (in VEE-troh)
In the laboratory (outside the body). The opposite of in vivo (in the body).

in vitro fertilization  (in VEE-troh FER-tih-lih-ZAY-shun)
A procedure in which eggs are removed from a woman’s ovary and combined with sperm outside the body to form embryos. The embryos are grown in the laboratory for several days and then either placed in a woman’s uterus or cryopreserved (frozen) for future use.

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

inalimarev  (IN-uh-LIM-uh-rev)
A cancer vaccine made with a form of vaccinia virus that does not cause disease in humans. It is being studied in the treatment of some types of cancer. The virus is changed in the laboratory to make human proteins, including the tumor markers called CEA and MUC-1, that may help immune cells in the body kill tumor cells. Also called recombinant vaccinia-CEA-MUC-1-TRICOM vaccine and PANVAC-V.

incidence  
The number of new cases of a disease diagnosed each year.

incision  (in-SIH-zhun)
A cut made in the body to perform surgery.

incisional biopsy  (in-SIH-zhun-al BY-op-see)
A surgical procedure in which a portion of a lump or suspicious area is removed for diagnosis. The tissue is then examined under a microscope.

incomplete Freund's adjuvant  (in-kum-PLEET froyndz A-juh-vunt)
A drug used in vaccine therapy to stimulate the immune system.

incontinence  (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 example, white blood cells can be grown in special conditions so that they attack specific cancer cells when returned to the body.

Indian cress  (IN-dee-un kres)
Parts of the flowering plant have been used in some cultures to treat certain medical problems. It may have anticancer effects. The scientific name is Nasturtium officinale. Also called watercress.

Indian elm  
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, sweet elm, Ulmus fulva, and Ulmus rubra.

Indian rhubarb  (IN-dee-un ROO-barb)
The root of this plant has been used in some cultures to treat certain medical problems. It may have anti-inflammatory and anticancer effects. The scientific name is Rheum palmatum or Rheum officinale. Also called rhubarb, da-huang, Chinese rhubarb, and Turkish rhubarb.

Indian saffron  (IN-dee-un SA-fron)
An East Indian plant that is a member of the ginger family and is used as a spice and food color. The underground stems are used in some cultures to treat certain stomach problems. The substance in Indian saffron that gives it a yellow color (curcumin) is being studied in the treatment of cancer, Alzheimer disease, cystic fibrosis, and psoriasis. The scientific name is Curcuma longa. Also called turmeric and jiang huang.

Indian valerian  
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, Valeriana officinalis, and Valerianae radix.

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

indinavir  
A drug that interferes with the ability of a virus to make copies of itself.

indirect ophthalmoscopy  (… OP-thal-MOS-koh-pee)
An exam of the inside of the back of the eye using a beam of light and a hand-held lens. Indirect ophthalmoscopy gives a wider view inside the eye than an exam using an ophthalmoscope does.

indium In 111 CHX-A DTPA trastuzumab  (IN-dee-um … tras-TOO-zuh-mab)
A substance being studied in the imaging of breast cancer and some other types of cancer. It is made by attaching a radioactive substance called indium 111 to the monoclonal antibody trastuzumab (Herceptin). Trastuzumab binds to the human growth factor receptor 2 (HER2/neu) on some breast cancer cells and on several other types of cancer cells. Indium In 111 CHX-A DTPA trastuzumab is a type of radioimmunoconjugate.

indium In 111 DOTA monoclonal antibody HuAFP31  (IN-dee-um … MAH-noh-KLOH-nul AN-tih-BAH-dee …)
A substance being studied in the treatment of liver cancer. It is made by attaching a radioactive substance called indium 111 to a monoclonal antibody called HuAFP31. HuAFP31 binds to tumor cells that make alpha fetoprotein (AFP), and the indium In 111 may kill the tumor cells. It is a type of radioimmunoconjugate.

indium In 111 ibritumomab tiuxetan  (IN-dee-um … ih-brih-TOO-moh-mab ty-oo-EKS-eh-tan)
A radiolabeled monoclonal antibody that is used to detect certain types of B-cell non-Hodgkin lymphoma and is being studied in the detection of other types of B-cell tumors. It is made up of the monoclonal antibody ibritumomab plus the radioisotope indium 111. It binds to the protein called CD20, which is found on B cells. A machine is used to detect which cells in the body have bound the antibody. Indium In 111 ibritumomab tiuxetan is a type of radiopharmaceutical. Also called In 111 ibritumomab tiuxetan and In 111 Zevalin.

indium In 111 pentetreotide  
An anticancer drug belonging to a family of drugs called radiopharmaceuticals.

indole-3-carbinol  
A substance that is being studied as a cancer prevention drug. It is found in cruciferous vegetables.

indolent  (IN-doe-lint)
A type of cancer that grows slowly.

indolent lymphoma  (IN-doh-lent lim-FOH-muh)
A type of lymphoma that tends to grow and spread slowly, and has few symptoms. Also called low-grade lymphoma.

indomethacin  (IN-doh-MEH-thuh-sin)
A drug that reduces pain, fever, swelling, and redness. It is also being used to reduce tumor-induced suppression of the immune system and to increase the effectiveness of anticancer drugs. It is a type of nonsteroidal anti-inflammatory drug (NSAID).

induction therapy  (in-DUK-shun THAYR-uh-pee)
Treatment designed to be used as a first step toward shrinking the cancer and in evaluating response to drugs and other agents. Induction therapy is followed by additional therapy to eliminate whatever 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 cancer treatments can weaken the natural defense system.

inferior vena cava  
A large vein that empties into the heart. It carries blood from the legs and feet and from organs in the abdomen and pelvis.

infertile  
Unable to produce children.

infertility  (IN-fer-TIH-lih-tee)
The inability to produce children.

infiltrating breast cancer  
Cancer that has spread from where it started in the breast into surrounding, healthy tissue. Most infiltrating breast cancers start in the ducts (tubes that carry milk from the lobules to the nipple). Infiltrating breast cancer can spread to other parts of the body through the blood and lymph systems. Also called invasive breast cancer.

infiltrating cancer  
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  (IN-fluh-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 bowel disease  (in-FLA-muh-TOR-ee BOW-ul dih-ZEEZ)
A general term that refers to the inflammation of the colon and rectum. Inflammatory bowel disease includes ulcerative colitis and Crohn 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.

infliximab  
A monoclonal antibody that blocks the action of a cytokine called tumor necrosis factor alfa. It is being studied in the treatment and prevention of weight loss and loss of appetite in patients with advanced cancer. It belongs to the family of drugs called monoclonal antibodies.

informed consent  
A process in which a person is given important facts about a medical procedure or treatment, a clinical trial, or genetic testing before deciding whether or not to participate. It also includes informing the patient when there is new information that may affect his or her decision to continue. Informed consent includes information about the possible risks, benefits, and limits of the procedure, treatment, trial, or genetic testing.

infrared coagulation  
A technique in which abnormal tissue is exposed to a burst of infrared light (a type of radiation). This causes blood in veins in the tissue to coagulate (harden) and the abnormal tissue to shrink. It is being studied in the prevention of anal cancer in some patients with HIV.

infrared thermography  (IN-fruh-RED ther-MAH-gruh-fee)
In medicine, a procedure in which an infrared camera (one that senses heat) is used to measure temperature differences on the surface of the body. The camera makes pictures that show areas of possible abnormal cell growth because abnormal tissue gives off more heat than normal tissue does.

infusion  (in-FYOO-zhun)
A method of putting fluids, including drugs, into the bloodstream. Also called intravenous infusion.

ingestion  
Taking into the body by mouth.

inguinal orchiectomy  (IN-gwih-nul OR-kee-EK-toh-mee)
An operation in which the testicle is removed through an incision in the groin.

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

inhaler  (in-HAY-ler)
A device for giving medicines in the form of a spray that is inhaled (breathed in) through the nose or mouth. Inhalers are used to treat medical problems such as bronchitis, angina, emphysema, and asthma. They are also used to help relieve symptoms that occur when a person is trying to quit smoking.

inherited  (in-HAYR-it-ed)
Transmitted through genes that have been passed from parents to their offspring (children).

inherited bone marrow failure syndrome  (in-HAYR-it-ed bone MAYR-oh FAYL-yer SIN-drome)
IBMFS. A rare disorder in which a person’s bone marrow is unable to make enough blood cells and there is a family history of the same disorder. There are several different types of inherited bone marrow failure syndrome, and patients with one of them are at high risk of forming acute leukemia or certain solid tumors. Also called IBMFS.

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

Innohep  (IN-oh-HEP)
A drug that is used with another drug, warfarin, to treat blood clots that form deep in the veins and to prevent new blood clots from forming. It is a type of anticoagulant. Also called tinzaparin and tinzaparin sodium.

inoperable  
Describes a condition that cannot be treated by surgery.

inositol  (ih-NAH-sih-TOL)
A type of sugar that has a different chemical structure than glucose (the chief source of energy for living organisms). It is a basic part of cell membranes, and is important in nerve, brain, and muscle function. Inositol is found in many foods that come from plants, and is being studied in the prevention of cancer.

inositol hexaphosphate  (ih-NAH-sih-TOL HEK-suh-FOS-fayt)
IP6. A substance found in many foods that come from plants, including corn, wheat, rice, and soybeans, and in large amounts in cereals and legumes. It is being studied in the prevention of cancer. Also called phytic acid and IP6.

INS316  
A substance being studied in the diagnosis of lung diseases, including lung cancer. It helps bring up a sample of mucus from deep in the lungs and improves the quality of the sample for testing. It is a type of nucleoside triphosphate.

insomnia  
Difficulty in going to sleep or getting enough sleep.

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

Institutional Review Board  
A group of scientists, doctors, clergy, and consumers that reviews and approves the action plan for every clinical trial. There is an Institutional Review Board at every health care facility that does clinical research. Institutional Review Boards are designed to protect the people who take part in a clinical trial. Institutional Review Boards check to see that the trial is well designed, legal, ethical, does not involve unneccesary risks, and includes safeguards for patients. Also called IRB.

insulin  (IN-su-lin)
A hormone made by the islet cells of the pancreas. Insulin controls the amount of sugar in the blood by moving it into the cells, where it can be used by the body for energy.

intensification therapy  (in-TEN-sih-fih-KAY-shun THAYR-uh-pee)
A type of high-dose chemotherapy often given as the second phase (after induction therapy) of a cancer treatment regimen for leukemia. Also called consolidation therapy.

intensity-modulated radiation therapy  (in-TEN-sih-tee-MAH-juh-LAY-tid RAY-dee-AY-shun THAYR-uh-pee)
IMRT. A type of 3-dimensional 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. Also called IMRT.

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 cancer.

interfering thought  (IN-ter-FEER-ing thawt)
An unpleasant memory or idea that occurs often in a person’s everyday thoughts and keeps him or her from thinking about other things. Interfering thoughts can make sleep difficult and make a person unable to carry out daily activities. Also called intrusive thought.

interferon  (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 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 cancer and other diseases.

interleukin  (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 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 interleukin-1, interleukin-1-alfa and interleukin-1-beta. Both forms of interleukin-1 are produced by the body, and can also be made in the laboratory. Also called IL-1.

interleukin-1-alfa  
IL-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 interleukin-1-alpha, IL-1-alpha, and IL-1-alfa.

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). Interleukin-1-alpha stimulates the growth and action of immune system cells that fight disease. Interleukin-1-alpha is normally produced by the body, but it can also be made in the laboratory. Also called IL-1-alpha, interleukin-1-alfa, and IL-1-alfa.

interleukin-11  (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 IL-11 and oprelvekin.

interleukin-12  (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. Also called IL-12.

interleukin-13 PE38QQR immunotoxin  (in-ter-LOO-kin … IH-myoo-noh-TOK-sin)
A substance being studied in the treatment of cancer. It is made by combining interleukin-13 with a toxin from Pseudomonas bacteria. It is a type of recombinant chimeric protein.

interleukin-2  (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  (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. Also called IL-3.

interleukin-4  (in-ter-LOO-kin... )
One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body. Interleukin-4 is made by a type of T cell (white blood cell that attacks virus-infected cells, foreign cells, and cancer cells). It causes B lymphocytes to increase and to make antibodies and also increases the production of T cells. Interleukin-4 made in the laboratory is being used as a biological response modifier to boost the immune system in cancer therapy. Interleukin-4 is a type of cytokine. Also called IL-4.

interleukin-4 PE38KDEL cytotoxin  (in-ter-LOO-kin ... SY-toh-TOK-sin)
A substance being studied in the treatment of cancer. It is made by combining interleukin-4 with a bacterial toxin. Interleukin-4 PE38KDEL cytotoxin is a type of recombinant chimeric protein. Also called NBI-3001 and interleukin-4 PE38KDEL immunotoxin.

interleukin-4 PE38KDEL immunotoxin  (in-ter-LOO-kin ... IH-myoo-noh-TOK-sin)
A substance being studied in the treatment of cancer. It is made by combining interleukin-4 with a bacterial toxin. Interleukin-4 PE38KDEL immunotoxin is a type of recombinant chimeric protein. Also called NBI-3001 and interleukin-4 PE38KDEL cytotoxin.

interleukin-6  (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. Also called IL-6.

interleukin-7  (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. Interleukin-7 is made by cells in the bone marrow, and can stimulate T cells and B cells to grow. Interleukin-7 can also be made in the laboratory for use in treating cancer and other diseases. Also called IL-7.

intermediate-grade lymphoma  
A type of lymphoma that grows and spreads quickly, and has severe symptoms. It is seen frequently in patients who are HIV-positive (AIDS-related lymphoma). Also called aggressive lymphoma and high-grade lymphoma.

internal examination  (in-TER-nul ex-am-ih-NAY-shun)
A physical examination in which the health care professional will feel for lumps or changes in the shape of the vagina, cervix, uterus, fallopian tubes, ovaries, and rectum. The health care professional will also use a speculum to open the vagina to look at the cervix and take samples for a PAP test. Also called a pelvic examination.

internal radiation therapy  (in-TER-nul RAY-dee-AY-shun THAYR-uh-pee)
A type of radiation therapy in which radioactive material sealed in needles, seeds, wires, or catheters is placed directly into or near a tumor. Also called brachytherapy, radiation brachytherapy, and implant radiation therapy.

International Unit  
A unit used to measure the activity of many vitamins, hormones, enzymes, and drugs. An International Unit is the amount of a substance that has a certain biological effect. For each substance there is an international agreement on the biological effect that is expected for 1 International Unit. Also called IU.

interstitial radiation therapy  (IN-ter-STIH-shul RAY-dee-AY-shun THAYR-uh-pee)
A type of internal radiation therapy in which radioactive material sealed in needles, seeds, wires, or catheters is placed directly into a tumor or body tissue.

intervention  (IN-ter-VEN-shun)
In medicine, a treatment or action taken to prevent or treat disease, or improve health in other ways.

intervention group  (IN-ter-VEN-shun groop)
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  (in-TES-tin)
The long, tube-shaped organ in the abdomen that completes the process of digestion. The intestine has two parts, the small intestine and the large intestine. Also called the bowel.

intoplicine  (in-TOP-lih-seen)
A substance that has been studied in the treatment of some types of cancer. Intoplicine blocks certain enzymes needed for cell division and DNA repair, and it may kill cancer cells. It is a type of topoisomerase inhibitor.

intoxicating pepper  (in-TOK-sih-KAYT-ing...)
An herb native to islands in the South Pacific. Substances taken from the root have been used in some cultures to relieve stress, anxiety, tension, sleeplessness, and problems of menopause. Intoxicating pepper may increase the effect of alcohol and of certain drugs used to treat anxiety and depression. The U.S. Food and Drug Administration advises users that intoxicating pepper may cause severe liver damage. The scientific name is Piper methysticum. Also called kava kava, rauschpfeffer, tonga, and yangona.

intra-arterial  (IN-truh-ar-TEER-ee-ul)
Within an artery (blood vessel that carries blood from the heart to tissues and organs in the body).

intracarotid infusion  (IN-truh-kuh-RAH-tid in-FYOO-zhun)
The introduction of fluids and drugs directly into the carotid artery, the main artery in the neck that carries blood from the heart to the brain.

intracavitary  (IN-truh-KA-vuh-tayr-ee)
Within a cavity or space, such as the abdomen, pelvis, or chest.

intracavitary radiation therapy  (IN-truh-KA-vih-tayr-ee RAY-dee-AY-shun THAYR-uh-pee)
A type of internal radiation therapy in which radioactive material sealed in needles, seeds, wires, or catheters is placed directly into a body cavity such as the chest cavity or the vagina.

intracellular  (IN-truh-SEL-yoo-ler)
Inside a cell.

intracolonic  
Within the colon.

intracranial tumor  (IN-truh-KRAY-nee-ul TOO-mer)
A tumor that occurs in the brain.

intracutaneous  (IN-truh-kyoo-TAY-nee-us)
Within the skin. Also called intradermal.

intradermal  (IN-truh-DER-mul)
Within the skin. Also called intracutaneous.

intraductal carcinoma  (IN-truh-DUK-tul KAR-sih-NOH-muh)
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, 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 and DCIS.

intraductal papilloma  (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  (IN-truh-eh-pih-THEEL-ee-ul)
Within the layer of cells that form the surface or lining of an organ.

intrahepatic  (IN-truh-heh-PA-tik)
Within the liver.

intrahepatic bile duct  (IN-truh-heh-PA-tik BILE dukt)
A bile duct that passes through and drains bile from the liver.

intrahepatic infusion  (IN-truh-heh-PA-tik in-FYOO-zhun)
The delivery of anticancer drugs directly to the blood vessels of the liver.

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

intraluminal intubation and dilation  
A procedure in which a plastic or metal tube is inserted through the mouth into the esophagus (the tube that carries food to the stomach) to keep it open. This procedure may be used during radiation therapy for esophageal cancer.

intramuscular  (IN-truh-MUS-kyoo-ler)
IM. Within or into muscle. Also called IM.

intramuscular injection  (IN-truh-MUS-kyoo-ler in-JEK-shun)
Injection into muscle.

intraocular  (IN-truh-AH-kyoo-ler)
Within the eyeball.

intraocular melanoma  (IN-truh-AH-kyoo-ler MEH-luh-NOH-muh)
A rare cancer of melanocytes (cells that produce the pigment melanin) found in the eye. Also called ocular melanoma.

intraoperative radiation therapy  (IN-truh-AH-puh-ruh-tiv RAY-dee-AY-shun THAYR-uh-pee)
IORT. Radiation treatment aimed directly at a tumor during surgery. Also called IORT.

intrapelvic  (IN-truh-PEL-vik)
Within the pelvis, the lower part of the abdomen between the hip bones.

intraperitoneal  (IN-truh-PAYR-ih-toh-NEE-ul)
IP. Within the peritoneal cavity (the area that contains the abdominal organs). Also called IP.

intraperitoneal chemotherapy  (IN-truh-PAYR-ih-toh-NEE-ul KEE-moh-THAYR-uh-pee)
Treatment in which anticancer drugs are put directly into the abdominal cavity through a thin tube.

intraperitoneal infusion  (IN-truh-PAYR-ih-toh-NEE-ul in-FYOO-zhun)
A method of delivering fluids and drugs directly into the abdominal cavity through a thin tube. Also called peritoneal infusion.

intraperitoneal radiation therapy  (IN-truh-PAYR-ih-toh-NEE-ul RAY-dee-AY-shun THAYR-uh-pee)
Treatment in which a radioactive liquid is put directly into the abdomen through a thin tube.

intrapleural  
Within the pleural cavity.

intraspinal  (IN-truh-SPY-nul)
Within the spine (backbone).

intrathecal  (IN-truh-THEE-kul)
Describes the fluid-filled space between the thin layers of tissue that cover the brain and spinal cord. Drugs can be injected into the fluid or a sample of the fluid can be removed for testing.

intrathecal chemotherapy  (IN-truh-THEE-kul KEE-moh-THAYR-uh-pee)
Treatment in which anticancer drugs are injected into the fluid-filled space between the thin layers of tissue that cover the brain and spinal cord.

intratumoral  
Within a tumor.

intrauterine  (IN-truh-YOO-teh-rin)
Inside the uterus (the small, hollow, pear-shaped organ in a woman’s pelvis where a baby grows).

intrauterine device  (IN-truh-YOO-teh-rin dee-VICE)
A small, plastic T-shaped device that is placed inside the uterus (the small, hollow, pear-shaped organ in a woman’s pelvis) to prevent pregnancy. Intrauterine devices prevent sperm from fertilizing an egg, and prevent fertilized eggs from implanting in the uterus. The use of intrauterine devices is also being studied in the prevention and treatment of endometrial cancer and other conditions. Also called IUD.

intravaginal  (IN-truh-VA-jih-nul)
Having to do with the inside of the vagina (the birth canal).

intravenous  (IN-truh-VEE-nus)
Into or within a vein. Intravenous usually refers to a way of giving a drug or other substance through a needle or tube inserted into a vein. Also called I.V.

intravenous infusion  (IN-truh-VEE-nus in-FYOO-zhun)
A method of putting fluids, including drugs, into the bloodstream. Also called infusion.

intravenous injection  (IN-truh-VEE-nus in-JEK-shun)
Injection into a vein.

intravenous pyelogram  (IN-truh-VEE-nus PY-eh-loh-GRAM)
IVP. A series of x-rays of the kidneys, ureters, and bladder. The x-rays are taken after a dye is injected into a blood vessel. The dye is concentrated in the urine, which outlines the kidneys, ureters, and bladder on the x-rays. Also called IVP and intravenous pyelography.

intravenous pyelography  (IN-truh-VEE-nus PY-eh-LAH-gruh-fee)
IVP. X-ray study of the kidneys, ureters, and bladder. The x-rays are taken after a dye is injected into a blood vessel. The dye is concentrated in the urine, which outlines the kidneys, ureters, and bladder on the x-rays. Also called IVP and intravenous pyelogram.

intraventricular infusion  (IN-truh-ven-TRIH-kyoo-ler in-FYOO-zhun)
The delivery of a drug into a fluid-filled cavity within the heart or brain.

intravesical  (IN-truh-VES-ih-kal)
Within the bladder.

intrusive thought  (in-TROO-siv thawt)
An unpleasant memory or idea that occurs often in a person’s everyday thoughts and keeps him or her from thinking about other things. Interfering thoughts can make sleep difficult and make a person unable to carry out daily activities. Also called interfering thought.

invasive breast cancer  (in-VAY-siv brest KAN-ser)
Cancer that has spread from where it started in the breast into surrounding, healthy tissue. Most invasive breast cancers start in the ducts (tubes that carry milk from the lobules to the nipple). Invasive breast cancer can spread to other parts of the body through the blood and lymph systems. Also called infiltrating breast cancer.

invasive cancer  (in-VAY-siv KAN-ser)
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 cervical cancer  (in-VAY-siv SER-vih-kul KAN-ser)
Cancer that has spread from the surface of the cervix to tissue deeper in the cervix or to other parts of the body.

invasive hydatidiform mole  (in-VAY-siv hy-da-TID-ih-form mohl)
A type of cancer that grows into the muscular wall of the uterus. It is formed after conception (fertilization of an egg by a sperm). It may spread to other parts of the body, such as the vagina, vulva, and lung. Also called chorioadenoma destruens.

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

inverted papilloma  
A type of tumor in which surface epithelial cells grow downward into the underlying supportive tissue. It may occur in the nose and/or sinuses or in the urinary tract (bladder, renal pelvis, ureter, urethra). When it occurs in the nose or sinuses, it may cause symptoms similar to those caused by sinusitis, such as nasal congestion. When it occurs in the urinary tract, it may cause blood in the urine.

investigational  (in-VES-tih-GAY-shuh-nul)
In clinical trials, refers to a drug (including a new drug, dose, combination, or route of administration) or procedure that has undergone basic laboratory testing and received approval from the U.S. Food and Drug Administration (FDA) to be tested in human subjects. A drug 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.

investigational drug  (in-VES-tih-GAY-shuh-nul drug)
A substance that has been tested in a laboratory and has gotten approval from the U.S. Food and Drug Administration (FDA) to be tested in people. A drug 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 drug.

investigator  
A researcher in a clinical trial or clinical study.

inviable  
Not able to survive.

involuntary  (in-VAH-lun-TAYR-ee)
An action that is not made by choice. In the body, involuntary actions (such as blushing) occur automatically, and cannot be controlled by choice.

involuntary nervous system  (in-VAH-lun-TAYR-ee NER-vus SIS-tem)
The part of the nervous system that controls muscles of internal organs (such as the heart, blood vessels, lungs, stomach, and intestines) and glands (such as salivary glands and sweat glands). One part of the involuntary nervous system helps the body rest, relax, and digest food and another part helps a person fight or take flight in an emergency. Also called autonomic nervous system or ANS.

iodine  (I-oh-dine)
An element that is necessary for the body to make thyroid hormone. It is found in shellfish and iodized salt.

iodine I 131 metaiodobenzylguanidine  (I-oh-dine ... meh-tuh-I-oh-doh-BEN-zeel-GWAH-nih-deen)
A radioactive substance that is used in imaging tests, and is being studied in the treatment of cancer. It is a type of radiopharmaceutical. Also called 131I-MIBG.

iodine I 131 monoclonal antibody BC8  (I-oh-dine … MAH-noh-KLOH-nul AN-tee-BAH-dee…)
A monoclonal antibody that contains the radioactive substance iodine I131. It is being studied in the treatment of acute myeloid leukemia. Monoclonal antibodies are made in the laboratory and can locate and bind to cancer cells. Iodine I 131 monoclonal antibody BC8 binds to the protein CD45, which is found on most white blood cells and myeloid and lymphoid leukemia cells.

iodine I 131 tositumomab  (I-oh-dine I 131 TAH-sih-TOO-moh-mab)
A monoclonal antibody (tositumomab) that has been chemically changed by adding radioactive iodine, and that is used in the treatment of certain types of non-Hodgkin lymphoma. It belongs to the family of drugs called radioconjugated monoclonal antibodies. When iodine I 131 tositumomab and tositumomab are given together, the combination is called the Bexxar regimen.

iododoxorubicin  (I-oh-doh-DOK-soh-ROO-bih-sin)
A substance that is being studied as a treatment for cancer and for primary systemic amyloidosis (a disease in which proteins are deposited in specific organs). It is a type of anthracycline antitumor antibiotic.

ionizing radiation  (I-uh-NYZ-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 cancer.

ionomycin  
An antibiotic drug used to treat infection.

IORT  
Intraoperative radiation therapy. Radiation treatment aimed directly at a tumor during surgery. Also called intraoperative radiation therapy.

IP  
Intraperitoneal. Within the peritoneal cavity (the area that contains the abdominal organs). Also called intraperitoneal.

IP6  
Inositol hexaphosphate. A substance found in many foods that come from plants, including corn, wheat, rice, and soybeans, and in large amounts in cereals and legumes. It is being studied in the prevention of cancer. Also called phytic acid and inositol hexaphosphate.

ipilimumab  (ih-pih-LIM-yoo-mab)
A monoclonal antibody being studied in the treatment of certain types of cancer. Ipilimumab is made in the laboratory and binds to the molecule CTLA-4 on T cells (a type of white blood cell). Ipilimumab may block CTLA-4 and help the immune system kill cancer cells. Also called MDX-010.

ipsilateral  
Having to do with the same side of the body.

IRB  
A group of scientists, doctors, clergy, and consumers that reviews and approves the action plan for every clinical trial. There is an IRB at every health care facility that does clinical research. IRBs are designed to protect the people who take part in a clinical trial. They check to see that the trial is well designed, legal, ethical, does not involve unneccesary risks, and includes safeguards for patients. Also called Institutional Review Board.

Iressa  (i-REH-suh)
A drug that is used to treat certain types of non-small cell lung cancer and is being studied in the treatment of other types of cancer. It is a type of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor. Also called ZD1839 and gefitinib.

irinotecan  
An anticancer drug that is a type of topoisomerase inhibitor. It is a camptothecin analog. Also called CPT 11.

iris  (I-ris)
The colored tissue at the front of the eye that contains the pupil in the center. The iris helps control the size of the pupil to let more or less light into the eye.

irofulven  (i-roh-FUL-ven)
A substance being studied in the treatment of some types of cancer. Irofulven attaches to the cell's DNA and may block cancer cell growth. It is a type of alkylating agent. Also called 6-hydroxymethylacylfulvene.

iron  (I-urn)
An important mineral the body needs to make hemoglobin, a substance in the blood that carries oxygen from the lungs to tissues throughout the body. Iron is also an important part of many other proteins and enzymes needed by the body for normal growth and development. It is found in red meat, fish, poultry, lentils, beans, and foods with iron added, such as cereal.

irradiated  
Treated with radiation.

irradiation  (ih-RAY-dee-AY-shun)
The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy) or it may come from radioactive materials placed in the body near cancer cells (internal radiation therapy). Systemic irradiation uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called radiation therapy and radiotherapy.

irreversible toxicity  (eer-ih-VER-sih-bul tok-SIH-sih-tee)
Side effects that are caused by toxic substances or something harmful to the body and do not go away.

iseganan hydrochloride  (i-seh-GAN-an HY-droh-KLOR-ide)
A substance being studied in the treatment of oral mucositis (painful mouth sores) caused by cancer therapy and other conditions. Iseganan hydrochloride kills certain bacteria, fungi, and viruses by making holes in their outer membranes and causing them to burst. It is a type of synthetic antimicrobial peptide and a type of synthetic protegrin analog.

ISIS 2503  
A substance that is being studied in the treatment of cancer.

ISIS 3521  
A substance that is being studied in the treatment of cancer.

ISIS 5132  
A substance that is being studied in the treatment of cancer.

islet cell  
A pancreatic cell that produces hormones (e.g., insulin and glucagon) that are secreted into the bloodstream. These hormones help control the level of glucose (sugar) in the blood. Also called endocrine pancreas cell and islet of Langerhans cell.

islet cell carcinoma  (I-let sel KAR-sih-NOH-muh)
A rare cancer that forms in the islets of Langerhans cells (a type of cell found in the pancreas). Also called pancreatic endocrine cancer.

islet cell tumor  (I-let sel TOO-mer)
A mass of abnormal cells that forms in the endocrine (hormone-producing) tissues of the pancreas. Islet cell tumors may be benign (noncancer) or malignant (cancerous).

islet of Langerhans cell  (EYE-let of LANG-er-hanz)
A pancreatic cell that produces hormones (e.g., insulin and glucagon) that are secreted into the bloodstream. These hormones help control the level of glucose (sugar) in the blood. Also called endocrine pancreas cell and islet cell.

isoflavone  
An estrogen-like substance made by some plants, including the soy plant. Soy isoflavones are being studied in the prevention of 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.

isolated hepatic perfusion  (I-soh-LAY-ted heh-PA-tik per-FYOO-zhun)
A procedure in which a catheter is placed into the artery that provides blood to the liver. A second catheter is placed into the vein that takes blood away from the liver. This temporarily separates the liver's blood supply from blood circulating throughout the rest of the body and allows high doses of anticancer drugs to be directed to the liver only.

isolated limb infusion  (I-soh-LAY-ted LIM in-FYOO-zhun)
A procedure used to deliver anticancer drugs directly to an arm or leg but not to the rest of the body. The flow of blood to and from the limb is temporarily stopped with a tourniquet (a tight band around the limb). Catheters (small, flexible tubes) attached to a pump are put into an artery and a vein in the limb so that blood can be circulated through the pump into the limb. Anticancer drugs are injected into the catheters. Wrapping the limb in a heated blanket or warming the drugs or blood may help the drugs work better.

isolated limb perfusion  (I-soh-LAY-ted LIM per-FYOO-zhun)
A procedure that may be used to deliver anticancer drugs directly to an arm or leg. The flow of blood to and from the limb is temporarily stopped with a tourniquet (a tight band around the limb), and anticancer drugs are put directly into the blood of the limb. This allows the person to receive a high dose of drugs in the area where the cancer occurred. Also called limb perfusion.

isolated lung perfusion  (I-soh-LAY-ted ... per-FYOO-zhun)
A surgical procedure during which the circulation of blood to the lungs is separated from the circulation of blood through the rest of the body, and a drug is delivered directly into the lung circulation. This allows a higher concentration of chemotherapy to reach tumors in the lungs.

isolation  (I-soh-LAY-shun)
State of being separated from others. Isolation is sometimes used to prevent disease from spreading.

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.

isosulfan blue  (I-soh-SUL-fan …)
A dye made in the laboratory that helps identify the sentinel lymph node (the first lymph node that cancer spreads to from a primary tumor). Isosulfan blue is injected at the edge of a tumor and travels through the lymph fluid to lymph nodes near the tumor. The sentinel lymph node is identified by removing lymph nodes that are stained with the blue dye and looking for cancer cells under a microscope.

isotope  (I-soh-tope)
A form of a chemical element in which the atoms have the same number of protons (part of the nucleus of an atom) but with a different number of neutrons (part of the nucleus of an atom). For example, carbon 12, carbon 13, and carbon 14 are isotopes of carbon. They all have six protons in the nucleus, but each has different number of neutrons. Isotopes may be used in certain medical tests and procedures.

isotretinoin  
A drug that is used in the treatment of acne and psoriasis and is being studied in cancer prevention. It is a type of retinoid. Also called 13-cis retinoic acid.

ispinesib  (is-PIN-eh-sib)
A substance being studied in the treatment of cancer. Ispinesib blocks a protein that tumor cells need to divide. It is a type of mitotic inhibitor. Also called SB-715992.

isthmus  (iz-muhs)
A narrow part inside the body that connects two larger structures.

ITP  
A condition in which platelets (blood cells that cause blood clots to form) are destroyed by the immune system. The low platelet count causes easy bruising and bleeding, which may be seen as purple areas in the skin, mucous membranes, and outer linings of organs. Also called idiopathic thrombocytopenic purpura and immune thrombocytopenic purpura.

itraconazole  
A drug used to prevent or treat fungal infections. It belongs to the family of drugs called antifungal agents.

IU  
A unit used to measure the activity of many vitamins, hormones, enzymes, and drugs. An IU is the amount of a substance that has a certain biological effect. For each substance there is an international agreement on the biological effect that is expected for 1 IU. Also called International Unit.

IUD  
A small, plastic T-shaped device that is placed inside the uterus (the small, hollow, pear-shaped organ in a woman’s pelvis) to prevent pregnancy. IUDs prevent sperm from fertilizing an egg, and prevent fertilized eggs from implanting in the uterus. The use of IUDs is also being studied in the prevention and treatment of endometrial cancer and other conditions. Also called intrauterine device.

IVP  
Intravenous pyelogram or intravenous pyelography (in-tra-VEE-nus PYE-el-o-gram or pye-LAH-gra-fee). A series of x-rays of the kidneys, ureters, and bladder. The x-rays are taken after a dye is injected into a blood vessel. The dye is concentrated in the urine, which outlines the kidneys, ureters, and bladder on the x-rays. Also called intravenous pyelogram and intravenous pyelography.

ixabepilone  (ix-ab-EP-ih-lone)
A drug used to treat metastatic or locally advanced breast cancer that has not improved after treatment with certain other anticancer drugs. It is also being studied in the treatment of other types of cancer. Ixabepilone stops the growth of tumor cells by blocking cell division. It is a type of epothilone analog. Also called BMS-247550 and Ixempra.

Ixempra  (ix-EM-pruh)
A drug used to treat metastatic or locally advanced breast cancer that has not improved after treatment with certain other anticancer drugs. It is also being studied in the treatment of other types of cancer. Ixempra stops the growth of tumor cells by blocking cell division. It is a type of epothilone analog. Also called ixabepilone and BMS-247550.

Back to TopBack to Top

A Service of the National Cancer Institute
Department of Health and Human Services National Institutes of Health USA.gov