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275 results found for:   
  B



B cell  
A white blood cell that comes from bone marrow. As part of the immune system, B cells make antibodies and help fight infections. Also called B lymphocyte.

B lymphocyte  
A white blood cell that comes from bone marrow. As part of the immune system, B lymphocytes make antibodies and help fight infections. Also called B cell.

B-cell acute lymphoblastic leukemia  (... sel uh-KYOOT LIM-foh-BLAS-tik loo-KEE-mee-uh)
A type of leukemia (blood cancer) in which too many B-cell lymphoblasts (immature white blood cells) are found in the blood and bone marrow. It is the most common type of acute lymphoblastic leukemia (ALL). Also called B-cell acute lymphocytic leukemia and precursor B-lymphoblastic leukemia.

B-cell acute lymphocytic leukemia  (... sel uh-KYOOT LIM-foh-SIH-tik loo-KEE-mee-uh)
A type of leukemia (blood cancer) in which too many B-cell lymphoblasts (immature white blood cells) are found in the blood and bone marrow. It is the most common type of acute lymphoblastic leukemia (ALL). Also called B-cell acute lymphoblastic leukemia and precursor B-lymphoblastic leukemia.

B-cell leukemia/lymphoma 2 protein  (... sel loo-KEE-mee-uh/lim-FOH-muh 2 PROH-teen)
A protein that helps control whether a cell lives or dies by blocking a type of cell death called apoptosis. The gene for the B-cell leukemia/lymphoma 2 protein is found on chromosome 18, and transfer of the B-cell leukemia/lymphoma 2 gene to a different chromosome is seen in many B-cell leukemias and lymphomas. This causes the B-cell leukemia/lymphoma 2 protein to be made in larger amounts, which may keep cancer cells from dying. Also called BCL2.

B-cell lymphoma  (…lim-FOH-muh)
A type of cancer that forms in B cells (a type of immune system cell). B-cell lymphomas usually occur in adults and may be either indolent (slow-growing) or aggressive (fast-growing). There are many different types of B-cell lymphomas, and prognosis and treatment depend on the type and stage of cancer.

B3 antigen  
A protein found on some tumor cells.

B43-PAP immunotoxin  (... IH-myoo-noh-TOK-sin)
A toxic substance linked to an antibody that attaches to tumor cells and kills them.

B7-1  
A molecule that helps control immune responses in the body. B7-1 is involved in stimulating T-cells.

bacillus Calmette-Guérin  (buh-SIH-lus KAL-met GAY-ran)
A weakened form of the bacterium Mycobacterium bovis (bacillus Calmette-Guérin) that does not cause disease. Bacillus Calmette-Guérin is used in a solution to stimulate the immune system in the treatment of bladder cancer and as a vaccine to prevent tuberculosis. Also called BCG.

backbone  
The bones, muscles, tendons, and other tissues that reach from the base of the skull to the tailbone. The backbone encloses the spinal cord and the fluid surrounding the spinal cord. Also called spinal column, spine, and vertebral column.

baclofen  (BAK-loh-fen)
A drug that is used to treat certain types of muscle spasms and is being studied in the treatment of liver cancer. Baclofen relaxes muscles by blocking certain nerve receptors in the spinal cord. It is a type of antispasmodic. Also called Kemstro and Lioresal.

baclofen/amitriptyline/ketamine gel  (bak-LOH-fen AM-ih-TRIP-tih-leen KEET-uh-meen JEL)
A substance being studied in the treatment of peripheral neuropathy (pain, numbness, tingling, burning, or weakness in the hands or feet) caused by chemotherapy. It contains three drugs, baclofen, amitriptyline, and ketamine, that relax muscles by blocking nerve receptors. The gel is applied to the skin of affected areas. It is a type of analgesic. Also called BAK gel.

bacteria  (bak-TEER-ee-uh)
A large group of single-cell microorganisms. Some cause infections and disease in animals and humans. The singular of bacteria is bacterium.

bacterial toxin  (bak-TEER-ee-ul TOK-sin)
A toxic substance, made by bacteria, that can be modified to kill specific tumor cells without harming normal cells.

BAK gel  
A substance being studied in the treatment of peripheral neuropathy (pain, numbness, tingling, burning, or weakness in the hands or feet) caused by chemotherapy. It contains three drugs, baclofen, amitriptyline, and ketamine, that relax muscles by blocking nerve receptors. The gel is applied to the skin of affected areas. It is a type of analgesic. Also called baclofen/amitriptyline/ketamine gel.

balloon angioplasty  (buh-LOON AN-jee-oh-PLAS-tee)
A procedure to enlarge the opening in a blood vessel that has become narrowed or blocked by plaque (a buildup of fat and cholesterol on the inner wall of the blood vessel). A small balloon is filled with air inside the blood vessel to push the plaque against the blood vessel wall and increase the opening.

barbiturate  (bar-BICH-u-rit)
A drug used to treat insomnia, seizures, and convulsions, and to relieve anxiety and tension before surgery. It belongs to the family of drugs called central nervous system (CNS) depressants.

barium enema  
A procedure in which a liquid with barium in it is put into the rectum and colon by way of the anus. Barium is a silver-white metallic compound that helps to show the image of the lower gastrointestinal tract on an x-ray.

barium solution  
A liquid containing barium sulfate that is used in x-rays to highlight parts of the digestive system.

barium swallow  
A series of x-rays of the esophagus. The x-ray pictures are taken after the person drinks a solution that contains barium. The barium coats and outlines the esophagus on the x-ray. Also called esophagram and upper GI series.

Barrett esophagus  (BA-ret ee-SAH-fuh-gus)
A condition in which the cells lining the lower part of the esophagus have changed or been replaced with abnormal cells that could lead to cancer of the esophagus. The backing up of stomach contents (reflux) may irritate the esophagus and, over time, cause Barrett esophagus.

barrier  (BAYR-ee-er)
Something that blocks, prevents, separates, or limits.

basal cell  (BAY-sul SEL)
A small, round cell found in the lower part (or base) of the epidermis, the outer layer of the skin.

basal cell carcinoma  (BAY-sul SEL KAR-sih-NOH-muh)
A type of skin cancer that arises from the basal cells, small round cells found in the lower part (or base) of the epidermis, the outer layer of the skin.

basal cell nevus syndrome  (BAY-sul SEL NEE-vus SIN-drome)
A genetic condition that causes unusual facial features and disorders of the skin, bones, nervous system, eyes, and endocrine glands. People with this syndrome have a higher risk of basal cell carcinoma. Also called Gorlin syndrome and nevoid basal cell carcinoma syndrome.

baseline  
An initial measurement that is taken at an early time point to represent a beginning condition, and is used for comparison over time to look for changes. For example, the size of a tumor will be measured before treatment (baseline) and then afterwards to see if the treatment had an effect.

basophil  
A type of white blood cell. Basophils are granulocytes.

batimastat  
An anticancer drug that belongs to the family of drugs called angiogenesis inhibitors. Batimastat is a matrix metalloproteinase inhibitor.

batracylin  (BA-truh-SY-lin)
A substance being studied in the treatment of cancer. It may kill cancer cells by causing damage to the DNA. Batracylin is a type of heterocyclic aryl amine.

BAY 12-9566  
An anticancer drug that belongs to the family of drugs called angiogenesis inhibitors.

BAY 43-9006  
A drug used to treat advanced kidney cancer and a type of liver cancer that cannot be removed by surgery. It is also being studied in the treatment of other types of cancer. BAY 43-9006 stops cells from dividing and may prevent the growth of new blood vessels needed for tumors to grow. It is a type of kinase inhibitor and a type of angiogenesis inhibitor. Also called Nexavar, sorafenib, and sorafenib tosylate.

BAY 56-3722  
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called camptothecins.

BAY 59-8862  
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called taxanes.

BB-10901  
A substance that combines a monoclonal antibody (huN901) with an anticancer drug (DM1), and is being studied in the treatment of certain cancers, including non-small cell lung cancer. Monoclonal antibodies are laboratory-produced substances that can locate and bind to cancer cells.

BBBD  
The use of drugs to create openings between cells in the blood-brain barrier. The blood-brain barrier is a protective network of blood vessels and tissue that protects the brain from harmful substances, but can also prevent anticancer drugs from reaching the brain. Once the barrier is opened, anticancer drugs may be infused into an artery that goes to the brain, in order to treat brain tumors. Also called blood-brain barrier disruption.

BBIC  
A substance being studied in the prevention of cancer. BBIC is made from soybeans, and is a type of serine proteinase inhibitor. Also called Bowman-Birk inhibitor concentrate.

BBR 2778  
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called antitumor antibiotics. Also called pixantrone.

BBR 3464  
A substance that is being studied in the treatment of cancer. It belongs to the family of platinum-based drugs.

BCG  
A weakened form of the bacterium Mycobacterium bovis (bacillus Calmette-Guérin) that does not cause disease. BCG is used in a solution to stimulate the immune system in the treatment of bladder cancer and as a vaccine to prevent tuberculosis. Also called bacillus Calmette-Guérin.

BCG solution  (… suh-LOO-shun)
A form of biological therapy for superficial (not invasive) bladder cancer. The solution is made from a weakened form of the bacterium Mycobacterium bovis (bacillus Calmette-Guérin) that does not cause disease but stimulates the body’s immune system. A catheter is used to place the BCG solution into the bladder where it is held for about two hours.

bcl-2 antisense oligodeoxynucleotide G3139  (... AN-tee-sents AH-lih-goh-dee-OK-see-NOO-klee-oh-TIDE ...)
A substance being studied in the treatment of cancer. It may kill cancer cells by blocking the production of a protein that makes cancer cells live longer and by making them more sensitive to anticancer drugs. It is a type of antisense oligodeoxyribonucleotide. Also called augmerosen, Genasense, and oblimersen.

BCL2  
A protein that helps control whether a cell lives or dies by blocking a type of cell death called apoptosis. The gene for BCL2 is found on chromosome 18, and transfer of the BCL2 gene to a different chromosome is seen in many B-cell leukemias and lymphomas. This causes the BCL2 protein to be made in larger amounts, which may keep cancer cells from dying. Also called B-cell leukemia/lymphoma 2 protein.

BCR-ABL fusion gene  (... FYOO-zhun JEEN)
A gene formed when pieces of chromosomes 9 and 22 break off and trade places. The ABL gene from chromosome 9 joins to the BCR gene on chromosome 22, to form the BCR-ABL fusion gene. The changed chromosome 22 with the fusion gene on it is called the Philadelphia chromosome. The BCR-ABL fusion gene is found in most patients with chronic myelogenous leukemia (CML), and in some patients with acute lymphoblastic leukemia (ALL) or acute myelogenous leukemia (AML).

BCX-1777  
A substance being studied in the treatment of some types of leukemia and lymphoma. It is a type of purine nucleoside phosphorylase (PNP) inhibitor. Also called forodesine and forodesine hydrochloride.

BDC  
A rare type of kidney cancer that grows and spreads quickly. It begins in the duct of Bellini in the kidney. Also called Bellini duct carcinoma.

Beckwith-Wiedemann syndrome  
A rare, overgrowth disorder in which babies are large at birth and may develop low blood sugar. Other common symptoms are a large tongue, large internal organs, and defects of the abdominal wall near the navel. Beckwith-Wiedemann syndrome increases the risk of developing certain cancers, especially Wilms tumor.

beclin 1  (BEH-klin …)
A protein involved in autophagy (the process by which a cell destroys proteins and other substances in its cytoplasm). Beclin 1 is found at lower levels in several types of cancer cells than in normal cells. It is a type of tumor suppressor.

beclomethasone  
A drug being studied in the treatment of graft-versus-host disease. It belongs to a family of drugs called corticosteroids.

behavior modification  (bee-HAY-vyer MAH-dih-fih-KAY-shun)
A technique used to help people change the way they react to certain triggers in the environment that cause a negative reaction. In cancer treatment, behavior modification may be used to help patients who have become nauseous during previous cancer treatments cope with nausea they feel when they enter the therapy room to begin a new round of treatment.

belinostat  (beh-LIN-oh-STAT)
A substance being studied in the treatment of cancer. Belinostat blocks enzymes needed for cell division and may kill cancer cells. It also prevents the growth of blood vessels needed for tumors to grow and may make tumor cells more sensitive to other anticancer drugs. It is a type of histone deacetylase (HDAC) inhibitor, a type of angiogenesis inhibitor, and a type of chemosensitizer. Also called PXD101.

Bellini duct carcinoma  (beh-LEE-nee dukt KAR-sih-NOH-muh)
A rare type of kidney cancer that grows and spreads quickly. It begins in the duct of Bellini in the kidney. Also called BDC.

Bence Jones protein  
A small protein made by plasma cells (white blood cells that produce antibodies). It is found in the urine of most people with multiple myeloma (cancer that begins in plasma cells).

bench-to-bedside  
A term used to describe the process by which the results of research done in the laboratory are directly used to develop new ways to treat patients.

bendamustine  (BEN-duh-MUS-teen)
The active ingredient in a drug that is used to treat chronic lymphocytic leukemia (CLL) and is being studied in the treatment of other types of cancer. Bendamustine may damage the DNA in cancer cells and kill them. It is a type of alkylating agent and a type of antimetabolite.

bendamustine hydrochloride  (BEN-duh-MUS-teen HY-droh-KLOR-ide)
A drug that is used to treat chronic lymphocytic leukemia (CLL) and is being studied in the treatment of other types of cancer. Bendamustine hydrochloride may damage the DNA in cancer cells and kill them. It is a type of alkylating agent and a type of antimetabolite. Also called Treanda.

benign  (beh-NINE)
Not cancerous. Benign tumors may grow larger but do not spread to other parts of the body.

benign breast disease  (beh-NINE brest dih-ZEEZ)
A common condition marked by benign (noncancerous) changes in breast tissue. These changes may include irregular lumps or cysts, breast discomfort, sensitive nipples, and itching. These symptoms may change throughout the menstrual cycle and usually stop after menopause. Also called fibrocystic breast changes, fibrocystic breast disease, and mammary dysplasia.

benign proliferative breast disease  (beh-NINE proh-LIH-fuh-ruh-tiv brest dih-ZEEZ)
A group of noncancerous conditions that may increase the risk of developing breast cancer. Examples include ductal hyperplasia, lobular hyperplasia, and papillomas.

benign prostatic hyperplasia  (beh-NINE prah-STA-tik HY-per-PLAY-zhuh)
A benign (noncancerous) condition in which an overgrowth of prostate tissue pushes against the urethra and the bladder, blocking the flow of urine. Also called benign prostatic hypertrophy and BPH.

benign prostatic hypertrophy  (beh-NINE prah-STA-tik hy-PER-troh-fee)
A benign (noncancerous) condition in which an overgrowth of prostate tissue pushes against the urethra and the bladder, blocking the flow of urine. Also called benign prostatic hyperplasia and BPH.

benign tumor  (beh-NINE TOO-mer)
A noncancerous growth that does not invade nearby tissue or spread to other parts of the body.

benzaldehyde  
A colorless oily liquid used as a flavoring agent and to make dyes, perfumes, and pharmaceuticals. Benzaldehyde is chemically related to benzene.

benzene  
A chemical that is used widely by the chemical industry, and is also found in tobacco smoke, vehicle emissions, and gasoline fumes. Exposure to benzene may increase the risk of developing leukemia.

benzoylphenylurea  
A substance being studied in the treatment of cancer. It is a type of antitubulin agent. Also called BPU.

benzydamine  (ben-ZIH-duh-meen)
A substance being studied as a mouth rinse treatment for oral mucositis (painful mouth sores) caused by cancer therapy. It is a type of nonsteroidal anti-inflammatory drug (NSAID).

bereavement  (beh-REEV-ment)
A state of sadness, grief, and mourning after the loss of a loved one.

bergamot  (BER-guh-mot)
A type of orange tree grown in Italy. The essential oil from the peel of this orange is used in perfume, to get rid of insects, and to flavor tea. Bergamot oil is also used in aromatherapy for depression, anxiety, and poor digestion. The scientific name for the bergamot orange tree is Citrus bergamia.

Beriplast P  
A substance used in surgical wound healing to cause a blood clot to form. It consists of blood-clotting factors found naturally in human blood.

best practice  
In medicine, treatment that experts agree is appropriate, accepted, and widely used. Health care providers are obligated to provide patients with the best practice. Also called standard of care and standard therapy.

beta alethine  
A substance that is being studied in the treatment of cancer. It belongs to a family of chemicals called disulfides.

beta carotene  (BAY-tuh KAYR-uh-teen)
A substance found in yellow and orange fruits and vegetables and in dark green, leafy vegetables. The body can make vitamin A from beta carotene. Beta carotene is being studied in the prevention of some types of cancer. It is a type of antioxidant.

beta hemolytic streptococcus group B  (BAY-tuh HEE-moh-LIH-tik STREP-toh-KAH-kus ...)
A type of bacterium often found in the vagina. It can cause systemic infections in people with suppressed immune systems.

beta-2-microglobulin  (MY-kroh-GLOB-yoo-lin)
A small protein normally found on the surface of many cells, including lymphocytes, and in small amounts in the blood and urine. An increased amount in the blood or urine may be a sign of certain diseases, including some types of cancer, such as multiple myeloma or lymphoma.

beta-endorphin  (BAY-tuh en-DOR-fin)
A substance produced in the brain, especially in the pituitary gland, that blocks the sensation of pain. It is produced in response to pain, exercise, and other forms of stress. It is a type of polypeptide hormone.

beta-glucan  
A type of polysaccharide (string of sugar molecules) obtained from several types of mushrooms. It is being studied as a treatment for cancer and as an immune system stimulant.

beta-human chorionic gonadotropin  
A hormone normally found in the blood and urine during pregnancy. It may also be produced by some tumor cells. An increased level of beta-human chorionic gonadotropin may be a sign of cancer of the testis, uterus, ovary, liver, stomach, pancreas, or lung. Beta-human chorionic gonadotropin may also be produced in response to certain conditions that are not cancer. Beta-human chorionic gonadotropin is being studied in the treatment of Kaposi sarcoma. Also called ß-hCG.

bevacizumab  (beh-vuh-SIH-zoo-mab)
A monoclonal antibody used in the treatment of colorectal cancer that has spread. It is also being studied in the treatment of other types of cancer. Bevacizumab binds to vascular endothelial growth factor (VEGF) and may stop the growth of new blood vessels needed for tumors to grow. It is a type of antiangiogenesis agent. Also called Avastin.

bexarotene  (bek-SAR-uh-teen)
A drug used to treat skin problems caused by cutaneous T-cell lymphoma that have not gotten better after other treatment. It is also being studied in the treatment of other types of cancer. Bexarotene is a type of retinoid. Also called LGD1069 and Targretin.

Bexxar regimen  (BEX-ar REH-jih-men)
A combination of monoclonal antibodies used to treat certain types of non-Hodgkin lymphoma. The monoclonal antibody tositumomab is given with iodine I 131 tositumomab (a form of tositumomab that has been chemically changed by adding radioactive iodine). Monoclonal antibodies are made in the laboratory and can locate and bind to substances in the body, including cancer cells. Also called iodine I 131 tositumomab, tositumomab, and tositumomab and iodine I 131 tositumomab.

BG00001  
A gene therapy agent that is being studied in the treatment of cancer. It belongs to the family of drugs called biological response modifiers.

BI 2536  
A substance being studied in the treatment of cancer. It prevents cells from dividing and may block the growth of some tumors. It is a type of mitotic inhibitor.

BI-RADS  
A method used by radiologists to interpret and report in a standardized manner the results of mammography, ultrasound, and MRI used in breast cancer screening and diagnosis. Also called Breast Imaging Reporting and Data System.

Biafine cream  
A topical preparation to reduce the risk of, and treat skin reactions to, radiation therapy.

bias  (BY-us)
In a scientific research study or clinical trial, a flaw in the study design or the method of collecting or interpreting information. Biases can lead to incorrect conclusions about what the study or clinical trial showed.

BIBF 1120  
A substance being studied in the treatment of some types of cancer. BIBF 1120 blocks enzymes needed for cells to grow, and may prevent the growth of new blood vessels needed for tumors to grow. It is a type of tyrosine kinase inhibitor. Also called tyrosine kinase inhibitor BIBF 1120.

BIBX 1382  
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called epidermal growth factor receptor (EGFR) inhibitors.

bicalutamide  (bye-ka-LOO-ta-mide)
An anticancer drug that belongs to the family of drugs called antiandrogens.

bidi  
A cigarette made by rolling tobacco by hand in a dried leaf from the tendu tree (a member of the ebony family). Most bidis are made in India and they come in different flavors.

bilateral  
Affecting both the right and left sides of the body.

bilateral cancer  
Cancer that occurs in both paired organs, such as both breasts or both ovaries.

bilateral nephrectomy  (by-LA-teh-rul neh-FREK-toh-mee)
Surgery to remove both kidneys.

bilateral prophylactic mastectomy  (by-LA-teh-rul PROH-fih-LAK-tik ma-STEK-toh-mee)
Surgery to remove both breasts in order to reduce the risk of developing breast cancer.

bilateral salpingo-oophorectomy  (by-LA-teh-rul sal-PIN-goh-oh-oh-foh-REK-toh-mee)
Surgery to remove both ovaries and both fallopian tubes.

bile  
A fluid made by the liver and stored in the gallbladder. Bile is excreted into the small intestine, where it helps digest fat.

bile duct  
A tube through which bile passes in and out of the liver.

bile duct cancer  (BILE dukt KAN-ser)
Cancer that forms in a bile duct. A bile duct is a tube that carries bile (fluid made by the liver that helps digest fat) between the liver and gallbladder and the intestine. Bile ducts include the common hepatic, cystic, and common bile ducts. Bile duct cancer may be found inside the liver (intrahepatic) or outside the liver (extrahepatic).

biliary  
Having to do with the liver, bile ducts, and/or gallbladder.

biliary system  (BIH-lee-AYR-ee SIS-tem)
The organs and ducts that make and store bile (a fluid made by the liver that helps digest fat), and release it into the small intestine. The biliary system includes the gallbladder and bile ducts inside and outside the liver. Also called biliary tract.

biliary tract  (BIH-lee-AYR-ee …)
The organs and ducts that make and store bile (a fluid made by the liver that helps digest fat), and release it into the small intestine. The biliary tract includes the gallbladder and bile ducts inside and outside the liver. Also called biliary system.

bilirubin  (bil-ih-ROO-bun)
Substance formed when red blood cells are broken down. Bilirubin is part of the bile, which is made in the liver and is stored in the gallbladder. The abnormal buildup of bilirubin causes jaundice.

binding agent  
A substance that makes a loose mixture stick together. For example, binding agents can be used to make solid pills from loose powders.

bioavailable  
The ability of a drug or other substance to be absorbed and used by the body. Orally bioavailable means that a drug or other substance that is taken by mouth can be absorbed and used by the body.

biochanin A  (BY-oh-KAH-nin)
An isoflavone found in soy products. Soy isoflavones (estrogen-like substances made by some plants) are being studied to see if they help prevent cancer.

biochemical reactions  
In living cells, chemical reactions that help sustain life and allow cells to grow.

biochemical recurrence  (BY-oh-KEH-mih-kul ree-KUR-ents)
A rise in the blood level of PSA (prostate-specific antigen) in prostate cancer patients after treatment with surgery or radiation. Biochemical recurrence may occur in patients who do not have symptoms. It may mean that the cancer has come back. Also called biochemical relapse and PSA failure.

biochemical relapse  (BY-oh-KEH-mih-kul REE-laps)
A rise in the blood level of PSA (prostate-specific antigen) in prostate cancer patients after treatment with surgery or radiation. Biochemical relapse may occur in patients who do not have symptoms. It may mean that the cancer has come back. Also called biochemical recurrence and PSA failure.

biochemist  (BY-oh-KEH-mist)
A scientist who has special training in the study of the chemicals and processes that occur in all living things.

biofeedback  
A method of learning to voluntarily control certain body functions such as heartbeat, blood pressure, and muscle tension with the help of a special machine. This method can help control pain.

bioinformatics  (BY-oh-in-for-MA-tix)
The science of using computers, databases, and math to organize and analyze large amounts of biological, medical, and health information. Information may come from many sources, including patient statistics, tissue specimens, genetics research, and clinical trials.

biologic agent  (BY-uh-LAH-jik AY-jent)
A substance that is made from a living organism or its products and is used in the prevention, diagnosis, or treatment of cancer and other diseases. Biologic agents include antibodies, interleukins, and vaccines. Also called biological agent and biological drug.

biological  (BY-oh-LAH-jih-kul)
Pertaining to biology or to life and living things. In medicine, refers to a substance made from a living organism or its products. Biologicals may be used to prevent, diagnose, treat or relieve of symptoms of a disease. For example, antibodies, interleukins, and vaccines are biologicals. Biological also refers to parents and children who are related by blood.

biological agent  (BY-oh-LAH-jih-kul AY-jent)
A substance that is made from a living organism or its products and is used in the prevention, diagnosis, or treatment of cancer and other diseases. Biological agents include antibodies, interleukins, and vaccines. Also called biologic agent and biological drug.

biological drug  (BY-oh-LAH-jih-kul...)
A substance that is made from a living organism or its products and is used in the prevention, diagnosis, or treatment of cancer and other diseases. Biological drugs include antibodies, interleukins, and vaccines. Also called biologic agent and biological agent.

biological profile  (BY-oh-LAH-jih-kul PROH-file)
A summary of the biological actions of a substance. A biological profile may come from patient data or from tests done in the laboratory or in animals.

biological response modifier therapy  (BY-oh-LAH-jih-kul reh-SPONTS MAH-dih-FY-er 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 biological response modifier therapy include monoclonal antibodies, growth factors, and vaccines. These agents may also have a direct antitumor effect. Also called biological therapy, biotherapy, BRM therapy, and immunotherapy.

biological therapy  (BY-oh-LAH-jih-kul 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 biological therapy include monoclonal antibodies, growth factors, and vaccines. These agents may also have a direct antitumor effect. Also called biological response modifier therapy, biotherapy, BRM therapy, and immunotherapy.

biomarker  (BY-oh-MAR-ker)
A biological molecule found in blood, other body fluids, or tissues that is a sign of a normal or abnormal process, or of a condition or disease. A biomarker may be used to see how well the body responds to a treatment for a disease or condition. Also called molecular marker and signature molecule.

Biomed 101  
A substance that is being studied for its ability to decrease the side effects of interleukin-2 (IL-2).

biomedicine  (BY-oh-MEH-dih-sin)
A system in which medical doctors and other healthcare professionals (such as nurses, pharmacists, and therapists) treat symptoms and diseases using drugs, radiation, or surgery. Also called allopathic medicine, conventional medicine, mainstream medicine, orthodox medicine, and Western medicine.

biometrics  (BY-oh-MEH-triks)
The science of collecting and analyzing biologic or health data using statistical methods. Biometrics may be used to help learn the possible causes of a cancer or how often a cancer occurs in a certain group of people. Also called biometry and biostatistics.

biometry  (by-AH-meh-tree)
The science of collecting and analyzing biologic or health data using statistical methods. Biometry may be used to help learn the possible causes of a cancer or how often a cancer occurs in a certain group of people. Also called biometrics and biostatistics.

biopsy  (BY-op-see)
The removal of cells or tissues for examination by a pathologist. The pathologist may study the tissue under a microscope or perform other tests on the cells or tissue. There are many different types of biopsy procedures. The most common types include: (1) incisional biopsy, in which only a sample of tissue is removed; (2) excisional biopsy, in which an entire lump or suspicious area is removed; and (3) needle biopsy, in which a sample of tissue or fluid is removed with a needle. When a wide needle is used, the procedure is called a core biopsy. When a thin needle is used, the procedure is called a fine-needle aspiration biopsy.

biopsy specimen  
Tissue removed from the body and examined under a microscope to determine whether disease is present.

biorepository  (BY-oh-reh-PAH-zih-TOR-ee)
A facility that collects, catalogs, and stores samples of biological material, such as urine, blood, tissue, cells, DNA, RNA, and protein, from humans, animals, or plants for laboratory research. If the samples are from people, medical information may also be stored along with a written consent to use the samples in laboratory studies.

biospecimen  (BY-oh-SPEH-sih-men)
Samples of material, such as urine, blood, tissue, cells, DNA, RNA, and protein from humans, animals, or plants. Biospecimens are stored in a biorepository and are used for laboratory research. If the samples are from people, medical information may also be stored along with a written consent to use the samples in laboratory studies.

biostatistics  (BY-oh-stuh-TIS-tix)
The science of collecting and analyzing biologic or health data using statistical methods. Biostatistics may be used to help learn the possible causes of a cancer or how often a cancer occurs in a certain group of people. Also called biometrics and biometry.

biotherapy  (BY-oh-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 biotherapy include monoclonal antibodies, growth factors, and vaccines. These agents may also have a direct antitumor effect. Also called biological response modifier therapy, biological therapy, BRM therapy, and immunotherapy.

biotin  (BY-oh-tin)
A nutrient in the vitamin B complex that the body needs in small amounts to function and stay healthy. Biotin helps some enzymes break down substances in the body for energy and helps tissues develop. It is found in yeast, whole milk, egg yolks, and organ meats. Biotin is water-soluble (can dissolve in water) and must be taken in every day. Not enough biotin can cause skin, nerve, and eye disorders. Biotin is present in larger amounts in some cancer tissue than in normal tissue. Attaching biotin to substances used to treat some types of cancer helps them find cancer cells. Also called vitamin H.

Birt-Hogg-Dube syndrome  
An inherited condition in which benign tumors develop in hair follicles on the head, chest, back, and arms. People who have this disorder may be at increased risk of developing colon or kidney cancer.

birth canal  
The muscular canal extending from the uterus to the exterior of the body. Also called vagina.

birth control pill  
A pill used to prevent pregnancy. It contains hormones that block the release of eggs from the ovaries. Most birth control pills include estrogen and progestin. Also called oral contraceptive pill.

bispecific antibody  
An antibody developed in the laboratory to recognize more than one protein on the surface of different cells. Examples include bispecific antibodies 2B1, 520C9xH22, mDX-H210, and MDX447.

bispecific monoclonal antibody  
A monoclonal antibody that binds two different types of antigen. Bispecific monoclonal antibodies do not occur naturally; they must be made in the laboratory.

bisphosphonate  (bis-FOS-foh-nayt)
A drug or substance used to treat hypercalcemia (abnormally high blood calcium) and bone pain caused by some types of cancer. Forms of bisphosphonates are also used to treat osteoporosis and for bone imaging. Bisphosphonates inhibit a type of bone cell that breaks down bone. Also called diphosphonate.

bisphosphonate-associated osteonecrosis  (bis-fos-FOH-nayt-uh-SOH-see-ay-ted OS-tee-oh-neh-KROH-sis)
The necrosis (death) of bone tissue caused by treatment with a bisphosphonate (a drug or substance used to treat osteoporosis, bone pain caused by some types of cancer, and high blood calcium). It commonly occurs in the jaw bones. There may be pain, swelling and infection in the areas of necrosis. Also called BON.

bizelesin  
An anticancer drug that belongs to the family of drugs called alkylating agents. It is also an antitumor antibiotic.

BL22 immunotoxin  (... IH-myoo-noh-TOK-sin)
A bacterial toxic substance linked to an antibody that attaches to cancer cells and kills them. It belongs to the family of drugs called bacterial immunotoxins.

black cohosh  
An eastern North American perennial herb. A substance obtained from the root of the plant has been used in some cultures to treat a number of medical problems. It is being studied in the treatment of hot flashes and other symptoms of menopause. The scientific name is Cimicifuga racemosa. Also called black snakeroot, bugbane, bugwort, and rattlesnake root.

black snakeroot  
An eastern North American perennial herb. A substance obtained from the root of the plant has been used in some cultures to treat a number of medical problems. It is being studied in the treatment of hot flashes and other symptoms of menopause. The scientific name is Cimicifuga racemosa. Also called black cohosh, bugbane, bugwort, and rattlesnake root.

bladder  (BLA-der)
The organ that stores urine.

bladder cancer  (BLA-der KAN-ser)
Cancer that forms in tissues of the bladder (the organ that stores urine). Most bladder cancers are transitional cell carcinomas (cancer that begins in cells that normally make up the inner lining of the bladder). Other types include squamous cell carcinoma (cancer that begins in thin, flat cells) and adenocarcinoma (cancer that begins in cells that make and release mucus and other fluids). The cells that form squamous cell carcinoma and adenocarcinoma develop in the inner lining of the bladder as a result of chronic irritation and inflammation.

blast  
An immature blood cell.

blast crisis  (blast KRY-sis)
A phase of chronic myelogenous leukemia in which tiredness, fever, and an enlarged spleen occur during the blastic phase, when more than 30% of the cells in the blood or bone marrow are blast cells (immature blood cells).

blastic phase chronic myelogenous leukemia  (BLAS-tik FAYZ KRAH-nik MY-eh-LAH-jeh-nus loo-KEE-mee-uh)
A phase of chronic myelogenous leukemia in which 20% or more of the cells in the blood or bone marrow are blast cells (immature blood cells). When tiredness, fever, and an enlarged spleen occur during the blastic phase, it is called blast crisis.

bleomycin  
An anticancer drug that belongs to the family of drugs called antitumor antibiotics.

blessed thistle  (... THIH-sel)
A plant whose leaves, stems, and flowers have been used in some cultures to treat certain medical problems. Blessed thistle may have anti-inflammatory and anticancer effects. The scientific name is Cnicus benedictus. Also called cardin, holy thistle, spotted thistle, and St. Benedict's thistle.

blinded study  
A type of study in which the patients (single-blinded) or the patients and their doctors (double-blinded) do not know which drug or treatment is being given. The opposite of a blinded study is an open label study.

bloating  (BLOH-ting)
A swelling or feeling of fullness in the abdomen. Bloating is usually the result of gas in the intestines and can be caused by many things, including overeating, lactose intolerance, and constipation. Bloating can also be a side effect of cancer or cancer treatment.

blood  
A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.

blood cell count  
A test to check the number of red blood cells, white blood cells, and platelets in a sample of blood. Also called CBC and complete blood count.

blood chemistry study  
A procedure in which a sample of blood is examined to measure the amounts of certain substances made in the body. An abnormal amount of a substance can be a sign of disease in the organ or tissue that produces it.

blood clot  
A mass of blood that forms when blood platelets, proteins, and cells stick together. When a blood clot is attached to the wall of a blood vessel, it is called a thrombus. When it moves through the bloodstream and blocks the flow of blood in another part of the body, it is called an embolus.

blood poisoning  
Disease caused by the spread of bacteria and their toxins in the bloodstream. Also called septicemia and toxemia.

blood pressure  (blud PREH-sher)
The force of circulating blood on the walls of the arteries. Blood pressure is taken using two measurements: systolic (measured when the heart beats, when blood pressure is at its highest) and diastolic (measured between heart beats, when blood pressure is at its lowest). Blood pressure is written with the systolic blood pressure first, followed by the diastolic blood pressure (for example 120/80).

blood stasis  (blud STAY-sis)
In traditional Chinese medicine, a condition described as slowing or pooling of blood, which may cause pain or other symptoms.

blood thinner  
A drug that helps prevent blood clots from forming. Also called anticoagulant.

blood transfusion  
The administration of blood or blood products into a blood vessel.

blood urea nitrogen  (blud yoo-REE-uh NY-truh-jen)
Nitrogen in the blood that comes from urea (a substance formed by the breakdown of protein in the liver). The kidneys filter urea out of the blood and into the urine. A high level of urea nitrogen in the blood may be a sign of a kidney problem. Also called BUN and urea nitrogen.

blood vessel  
A tube through which the blood circulates in the body. Blood vessels include a network of arteries, arterioles, capillaries, venules, and veins.

blood-brain barrier  
A network of blood vessels with closely spaced cells that makes it difficult for potentially toxic substances (such as anticancer drugs) to penetrate the blood vessel walls and enter the brain.

blood-brain barrier disruption  
The use of drugs to create openings between cells in the blood-brain barrier. The blood-brain barrier is a protective network of blood vessels and tissue that protects the brain from harmful substances, but can also prevent anticancer drugs from reaching the brain. Once the barrier is opened, anticancer drugs may be infused into an artery that goes to the brain, in order to treat brain tumors. Also called BBBD.

BMD  
A measure of the amount of minerals (mostly calcium and phosphorous) contained in a certain volume of bone. BMD measurements are used to diagnose osteoporosis (a condition marked by decreased bone mass), to see how well osteoporosis treatments are working, and to predict how likely the bones are to break. Low BMD can occur in patients treated for cancer. Also called bone density, bone mass, and bone mineral density.

BMD scan  
An imaging test that measures bone density (the amount of bone mineral contained in a certain volume of bone) by passing x-rays with two different energy levels through the bone. It is used to diagnose osteoporosis (decrease in bone mass and density). Also called bone mineral density scan, DEXA, DEXA scan, dual energy x-ray absorptiometric scan, dual x-ray absorptiometry, and DXA.

BMI  
Body mass index. A measure that relates body weight to height. BMI is sometimes used to measure total body fat and whether a person is a healthy weight. Excess body fat is linked to an increased risk of some diseases including heart disease and some cancers. Also called body mass index.

BMS-182751  
A substance being studied in the treatment of prostate and other types of cancer. It contains the metal platinum and may kill cancer cells by damaging their DNA and stopping them from dividing. It is a type of alkylating agent. Also called JM 216 and satraplatin.

BMS-184476  
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called mitotic inhibitors.

BMS-188797  
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called taxane analogs.

BMS-214662  
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called farnesyltransferase inhibitors.

BMS-247550  
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. BMS-247550 stops the growth of tumor cells by blocking cell division. It is a type of epothilone analog. Also called ixabepilone and Ixempra.

BMS-275291  
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called matrix metalloproteinase inhibitors (MMPIs).

BMS-354825  
A drug used to treat certain types of chronic myeloid leukemia and acute lymphoblastic leukemia. BMS-354825 is also being studied in the treatment of certain other blood diseases and types of cancer. BMS-354825 binds to and blocks BCR-ABL and other proteins that help cancer cells grow. It is a type of tyrosine kinase inhibitor. Also called dasatinib and Sprycel.

BMS-599626  
A substance that is being studied in the treatment of cancer. It belongs to the family of drugs called protein tyrosine kinase inhibitors.

body image  (BAH-dee IH-mij)
The way a person thinks about his or her body and how it looks to others.

body mass index  
A measure that relates body weight to height. BMI is sometimes used to measure total body fat and whether a person is a healthy weight. Excess body fat is linked to an increased risk of some diseases including heart disease and some cancers. Also called BMI.

bolus  
A single dose of drug usually injected into a blood vessel over a short period of time. Also called bolus infusion.

bolus infusion  (BOH-lus in-FYOO-zhun)
A single dose of drug usually injected into a blood vessel over a short period of time. Also called bolus.

BON  
The necrosis (death) of bone tissue caused by treatment with a bisphosphonate (a drug or substance used to treat osteoporosis, bone pain caused by some types of cancer, and high blood calcium). It commonly occurs in the jaw bones. There may be pain, swelling and infection in the areas of necrosis. Also called bisphosphonate-associated osteonecrosis.

bone cancer  (... KAN-ser)
Primary bone cancer is cancer that forms in cells of the bone. Some types of primary bone cancer are osteosarcoma, Ewing sarcoma, malignant fibrous histiocytoma, and chondrosarcoma. Secondary bone cancer is cancer that spreads to the bone from another part of the body (such as the prostate, breast, or lung).

bone density  (...DEN-sih-tee)
A measure of the amount of minerals (mostly calcium and phosphorous) contained in a certain volume of bone. Bone density measurements are used to diagnose osteoporosis (a condition marked by decreased bone mass), to see how well osteoporosis treatments are working, and to predict how likely the bones are to break. Low bone density can occur in patients treated for cancer. Also called BMD, bone mass, and bone mineral density.

bone marrow  (bone MAYR-oh)
The soft, sponge-like tissue in the center of most bones. It produces white blood cells, red blood cells, and platelets.

bone marrow ablation  (bone MAYR-oh uh-BLAY-shun)
The destruction of bone marrow using radiation or drugs.

bone marrow aspiration  (bone MAYR-oh as-pih-RAY-shun)
The removal of a small sample of bone marrow (usually from the hip) through a needle for examination under a microscope.

bone marrow biopsy  (bone MAYR-oh BY-op-see)
The removal of a sample of tissue from the bone marrow with a needle for examination under a microscope.

bone marrow cancer  (bone MAYR-oh KAN-ser)
Cancer that forms in the blood-forming stem cells of the bone marrow (soft sponge-like tissue in the center of most bones). Bone marrow cancer includes leukemias and multiple myeloma.

bone marrow metastasis  (bone MAYR-oh meh-TAS-tuh-sis)
Cancer that has spread from the original (primary) tumor to the bone marrow.

bone marrow transplantation  (bone MAYR-oh tranz-plan-TAY-shun)
A procedure to replace bone marrow that has been destroyed by treatment with high doses of anticancer drugs or radiation. Transplantation may be autologous (an individual's own marrow saved before treatment), allogeneic (marrow donated by someone else), or syngeneic (marrow donated by an identical twin).

bone mass  
A measure of the amount of minerals (mostly calcium and phosphorous) contained in a certain volume of bone. Bone mass measurements are used to diagnose osteoporosis (a condition marked by decreased bone mass), to see how well osteoporosis treatments are working, and to predict how likely the bones are to break. Low bone mass can occur in patients treated for cancer. Also called BMD, bone density, and bone mineral density.

bone metastasis  (...meh-TAS-tuh-sis)
Cancer that has spread from the original (primary) tumor to the bone.

bone mineral density  (... MIH-neh-rul DEN-sih-tee)
A measure of the amount of minerals (mostly calcium and phosphorous) contained in a certain volume of bone. Bone mineral density measurements are used to diagnose osteoporosis (a condition marked by decreased bone mass), to see how well osteoporosis treatments are working, and to predict how likely the bones are to break. Low bone mineral density can occur in patients treated for cancer. Also called BMD, bone density, and bone mass.

bone mineral density scan  (... MIH-neh-rul DEN-sih-tee skan)
An imaging test that measures bone density (the amount of bone mineral contained in a certain volume of bone) by passing x-rays with two different energy levels through the bone. It is used to diagnose osteoporosis (decrease in bone mass and density). Also called BMD scan, DEXA, DEXA scan, dual energy x-ray absorptiometric scan, dual x-ray absorptiometry, and DXA.

bone scan  
A technique to create images of bones on a computer screen or on film. A small amount of radioactive material is injected into a blood vessel and travels through the bloodstream; it collects in the bones and is detected by a scanner.

bone-seeking radioisotope  
A radioactive substance that is given through a vein, and collects in bone cells and in tumor cells that have spread to the bone. It kills cancer cells by giving off low-level radiation.

booster  
In medicine, refers to a vaccination given after a previous vaccination. A booster helps maintain or increase a protective immune response.

borderline personality disorder  (BOR-der-LINE PER-suh-NA-lih-tee dis-OR-der)
A serious mental illness marked by unstable moods and impulsive behavior. People with BPD have problems with relationships, family and work life, long-term planning, and self-identity. Symptoms include intense bouts of anger, depression, and anxiety that may lead to self-injury or suicide, drug or alcohol abuse, excessive spending, binge eating, or risky sex. A person with BPD who is diagnosed with cancer may be at an increased risk of suicide. Also called BPD.

boron neutron capture therapy  (BOR-on NOO-tron KAP-cher THAYR-uh-pee)
A type of radiation therapy. The patient is given an infusion that contains the element boron, which collects in tumor cells. The patient then receives radiation therapy with atomic particles called neutrons that come from a special machine. The neutrons interact with the boron in the tumor cells and kill them.

boronophenylalanine-fructose complex  
A substance used in a type of radiation therapy called boron neutron capture therapy. BPA-F is injected into a vein, and becomes concentrated in tumor cells. The patient then receives radiation treatment with atomic particles called neutrons. The neutrons react with the boron in BPA-F, producing radioactive particles that kill the tumor cells without harming normal cells. Also called BPA-F.

bortezomib  (bore-TEZ-oh-mib)
A drug used to treat multiple myeloma that has gotten worse during treatment with other anticancer drugs. It is also used to treat mantle cell lymphoma in patients who have already received at least one other type of treatment. Bortezomib is also being studied in the treatment of other types of cancer. It is a type of proteasome inhibitor and a type of dipeptidyl boronic acid. Also called PS-341 and Velcade.

Boswellia serrata  (bos-WEH-lee-uh seh-RAY-tuh)
A tree that belongs to the incense tree family. The tree’s amber-colored resin is used in incense. The resin has anti-inflammatory effects and has been used to treat arthritis, asthma, and ulcerative colitis. It is also being studied in the treatment of brain tumors. Also called frankincense tree.

botanical  
Having to do with, or derived from, plants.

bowel  (BOW-ul)
The long, tube-shaped organ in the abdomen that completes the process of digestion. The bowel has two parts, the small bowel and the large bowel. Also called intestine.

bowel function  (BOW-ul FUNK-shun)
The way the intestines work in terms of how often there are bowel movements, the ability to control when to have a bowel movement, and whether the stools are hard and dry as in constipation or watery as in diarrhea.

Bowen disease  (BOH-en dih-ZEEZ)
A skin disease marked by scaly or thickened patches on the skin and often caused by prolonged exposure to arsenic. The patches often occur on sun-exposed areas of the skin and in older, white men. These patches may become malignant (cancerous). Also called precancerous dermatitis and precancerous dermatosis.

Bowman-Birk inhibitor concentrate  (BOH-man-BIRK in-HIH-bih-ter KON-sun-TRAYT)
A substance being studied in the prevention of cancer. BBIC is made from soybeans, and is a type of serine proteinase inhibitor. Also called BBIC.

BPA-F  
A substance used in a type of radiation therapy called boron neutron capture therapy. BPA-F is injected into a vein, and becomes concentrated in tumor cells. The patient then receives radiation treatment with atomic particles called neutrons. The neutrons react with the boron in BPA-F, producing radioactive particles that kill the tumor cells without harming normal cells. Also called boronophenylalanine-fructose complex.

BPD  
Borderline personality disorder. A serious mental illness marked by unstable moods and impulsive behavior. People with BPD have problems with relationships, family and work life, long-term planning, and self-identity. Symptoms include intense bouts of anger, depression, and anxiety that may lead to self-injury or suicide, drug or alcohol abuse, excessive spending, binge eating, or risky sex. A person with BPD who is diagnosed with cancer may be at an increased risk of suicide. Also called borderline personality disorder.

BPH  
A benign (noncancerous) condition in which an overgrowth of prostate tissue pushes against the urethra and the bladder, blocking the flow of urine. Also called benign prostatic hyperplasia and benign prostatic hypertrophy.

BPU  
A substance being studied in the treatment of cancer. It is a type of antitubulin agent. Also called benzoylphenylurea.

brachial plexopathy  (BRAY-kee-ul pleks-AH-pah-thee)
A condition marked by numbness, tingling, pain, weakness, or limited movement in the arm or hand. It is caused by an impairment of the brachial plexus, a network of nerves that affect the arm and hand.

brachial plexus  (BRAY-kee-ul PLEKS-us)
A network of nerves that sends signals from the spine to the arm and hand.

brachytherapy  (BRAY-kee-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 implant radiation therapy, internal radiation therapy, and radiation brachytherapy.

BRAF gene  
A gene that makes a protein called B-RAF, which is involved in sending signals in cells and in cell growth. This gene may be mutated (changed) in many types of cancer, which causes a change in the B-RAF protein. This can increase the growth and spread of cancer cells.

brain metastasis  (...meh-TAS-tuh-sis)
Cancer that has spread from the original (primary) tumor to the brain.

brain stem  
The part of the brain that is connected to the spinal cord.

brain stem glioma  (...glee-OH-muh)
A tumor located in the part of the brain that connects to the spinal cord (the brain stem). It may grow rapidly or slowly, depending on the grade of the tumor.

brain stem tumor  
A tumor in the part of the brain that connects to the spinal cord (the brain stem).

brain tumor  
The growth of abnormal cells in the tissues of the brain. Brain tumors can be benign (non-cancerous) or malignant (cancerous).

Brassica vegetable  (BRA-sih-kuh VEJ-tuh-bul)
A member of the family of vegetables that includes broccoli, Brussels sprouts, cabbage, cauliflower, collard greens, kale, and turnips. These vegetables contain substances that may protect against cancer. Also called cruciferous vegetable.

BRCA1  
A gene on chromosome 17 that normally helps to suppress cell growth. A person who inherits a mutated (changed) BRCA1 gene has a higher risk of getting breast, ovarian, or prostate cancer.

BRCA2  
A gene on chromosome 13 that normally helps to suppress cell growth. A person who inherits a mutated (changed) BRCA2 gene has a higher risk of getting breast, ovarian, or prostate cancer.

breakthrough pain  
Intense increases in pain that occur with rapid onset even when pain-control medication is being used. Breakthrough pain can occur spontaneously or in relation to a specific activity.

breast  (brest)
Glandular organ located on the chest. The breast is made up of connective tissue, fat, and breast tissue that contains the glands that can make milk. Also called mammary gland.

breast cancer  (brest KAN-ser)
Cancer that forms in tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). It occurs in both men and women, although male breast cancer is rare.

breast carcinoma in situ  
Abnormal cells that are confined to the ducts or lobules in the breast. There are two forms, called ductal carcinoma in situ (DCIS) and lobular carcinoma in situ (LCIS). Also called stage 0 breast carcinoma in situ.

breast density  
Describes the relative amount of different tissues present in the breast. A dense breast has less fat than glandular and connective tissue. Mammogram films of breasts with higher density are harder to read and interpret than those of less dense breasts.

breast duct endoscopy  
A method used to examine the lining of the breast ducts to look for abnormal tissue. A very thin, flexible, lighted tube attached to a camera is inserted through the nipple, and threaded into the breast ducts deep in the breast. Tissue and fluid samples may be removed during the procedure.

Breast Imaging Reporting and Data System  (brest ih-mih-jing rih-port-ing SIS-tem)
A method used by radiologists to interpret and report in a standardized manner the results of mammography, ultrasound, and MRI used in breast cancer screening and diagnosis. Also called BI-RADS.

breast implant  
A silicone gel-filled or saline-filled sac placed under the chest muscle to restore breast shape.

breast reconstruction  
Surgery to rebuild the shape of the breast after a mastectomy.

breast self-exam  
An exam by a woman of her breasts to check for lumps or other changes.

breast-conserving surgery  
An operation to remove the breast cancer but not the breast itself. Types of breast-conserving surgery include lumpectomy (removal of the lump), quadrantectomy (removal of one quarter, or quadrant, of the breast), and segmental mastectomy (removal of the cancer as well as some of the breast tissue around the tumor and the lining over the chest muscles below the tumor). Also called breast-sparing surgery.

breast-sparing surgery  
An operation to remove the breast cancer but not the breast itself. Types of breast-sparing surgery include lumpectomy (removal of the lump), quadrantectomy (removal of one quarter, or quadrant, of the breast), and segmental mastectomy (removal of the cancer as well as some of the breast tissue around the tumor and the lining over the chest muscles below the tumor). Also called breast-conserving surgery.

breastbone  
The long flat bone that forms the center front of the chest wall. The breastbone is attached to the collarbone and the first seven ribs. Also called sternum.

Brief Pain Inventory  
A questionnaire used to measure pain.

brivanib  (brih-VAN-ib)
A substance being studied in the treatment of cancer. Brivanib blocks the growth of new blood vessels needed for tumors to grow and may kill cancer cells. It is a type of vascular endothelial growth factor receptor 2 inhibitor and a type of antiangiogenesis agent.

brivanib alaninate  (brih-VAN-ib a-luh-NIN-ayt)
A substance being studied in the treatment of cancer. Brivanib alaninate blocks the growth of new blood vessels needed for tumors to grow and may kill cancer cells. It is a type of vascular endothelial growth factor receptor 2 inhibitor and a type of antiangiogenesis agent.

brivudine  
A substance that is being studied in the treatment of infections caused by herpesvirus, including herpes-zoster (shingles). It belongs to the family of drugs called antivirals.

BRM therapy  (...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 BRM therapy include monoclonal antibodies, growth factors, and vaccines. These agents may also have a direct antitumor effect. Also called biological response modifier therapy, biological therapy, biotherapy, and immunotherapy.

broccoli sprout extract  (BRAH-kuh-lee … EK-strakt)
A substance being studied in the prevention of cancer. Broccoli sprout extract comes from newly sprouted broccoli. It causes cells to make enzymes that may protect them against cancer-causing toxins in the body, and it may also block the growth of cancer cells.

bromelain  
An enzyme found in pineapples that breaks down other proteins, such as collagen and muscle fiber, and has anti-inflammatory properties. It is used as a meat tenderizer in the food industry.

bronchi  (BRONG-ky)
The large air passages that lead from the trachea (windpipe) to the lungs.

bronchial  (BRON-kee-ul)
Having to do with the bronchi, which are the larger air passages of the lungs, including those that lead from the trachea (windpipe) to the lungs and those within the lungs.

bronchial adenoma  (BRON-kee-ul A-deh-NOH-muh)
Cancer that forms in tissues of the bronchi (large air passages in the lungs including those that lead to the lungs from the windpipe).

bronchiole  (BRONG-kee-ole)
A tiny branch of air tubes in the lungs.

bronchiolitis obliterans  (BRONG-kee-oh-LY-tis ob-LIT-eh-ranz)
A condition in which the bronchioles (tiny branches of air tubes in the lungs) become inflamed and blocked. It may be caused by breathing in gases or particles that irritate the bronchioles. This irritation causes scar tissue to form, and makes breathing difficult. Bronchiolitis olbiterans may be caused by other factors, and can also occur after a transplant with an organ or stem cells from a matched donor.

bronchitis  (bron-KYE-tis)
Inflammation (swelling and reddening) of the bronchi.

bronchodilator  (BRON-koh-DY-lay-ter)
A type of drug that causes small airways in the lungs to open up. Bronchodilators are inhaled and are used to treat breathing disorders, such as asthma or emphysema.

bronchogenic carcinoma  (BRON-koh-JEH-nik KAR-sih-NOH-muh)
Cancer that begins in the tissue that lines or covers the airways of the lungs, including small cell and non-small cell lung cancer.

bronchoscope  (BRON-koh-SKOPE)
A thin, tube-like instrument used to examine the inside of the trachea, bronchi (air passages that lead to the lungs), and lungs. A bronchoscope has a light and a lens for viewing, and may have a tool to remove tissue.

bronchoscopy  (bron-KOS-koh-pee)
A procedure that uses a bronchoscope to examine the inside of the trachea, bronchi (air passages that lead to the lungs), and lungs. A bronchoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease. The bronchoscope is inserted through the nose or mouth. Bronchoscopy may be used to detect cancer or to perform some treatment procedures.

bronchus  (BRON-kus)
A large airway that leads from the trachea (windpipe) to a lung. The plural of bronchus is bronchi.

brostallicin  (broh-STAL-ih-sin)
A substance being studied in the treatment of cancer. It is a type of DNA intercalator.

broxuridine  
A drug that makes cancer cells more sensitive to radiation and is also used as a diagnostic agent to determine how fast cancer cells grow.

bryostatin 1  (BRY-uh-STA-tin)
A substance being studied in the treatment of cancer and certain brain conditions such as Alzheimer disease and stroke. It binds to an enzyme involved in cell growth and it may help anticancer drugs work better. Bryostatin 1 comes from a marine organism. It is a type of protein kinase C modulator.

BSH  
A substance used in a type of radiation therapy called boron neutron capture therapy. BSH is injected into a vein and becomes concentrated in tumor cells. The patient then receives radiation treatment with atomic particles called neutrons. The neutrons react with the boron in BSH and make radioactive particles that kill the tumor cells without harming normal cells. Also called sodium borocaptate.

BSI-201  
A substance being studied in the treatment of cancer. It blocks enzymes that repair damage to DNA. This may help cancer treatments, such as radiation therapy and chemotherapy, kill more cancer cells. BSI-201 is a type of poly(ADP-ribose) polymerase inhibitor.

buccal mucosa  (BUH-kul myoo-KOH-suh)
The inner lining of the cheeks.

budesonide  
A drug used in the treatment of asthma and rhinitis. It is also being studied in the treatment of cancer. Budesonide belongs to the family of drugs called steroids.

bugbane  
An eastern North American perennial herb. A substance obtained from the root of the plant has been used in some cultures to treat a number of medical problems. It is being studied in the treatment of hot flashes and other symptoms of menopause. The scientific name is Cimicifuga racemosa. Also called black cohosh, black snakeroot, bugwort, and rattlesnake root.

bugwort  
An eastern North American perennial herb. A substance obtained from the root of the plant has been used in some cultures to treat a number of medical problems. It is being studied in the treatment of hot flashes and other symptoms of menopause. The scientific name is Cimicifuga racemosa. Also called black cohosh, black snakeroot, bugbane, and rattlesnake root.

bulk-forming agent  
A substance, such as fiber in food, that adds bulk and water to stools so that they can pass more easily through the intestines (lower part of the digestive tract).

BUN  
Nitrogen in the blood that comes from urea (a substance formed by the breakdown of protein in the liver). The kidneys filter urea out of the blood and into the urine. A high level of urea nitrogen in the blood may be a sign of a kidney problem. Also called blood urea nitrogen and urea nitrogen.

bupivacaine  (byoo-PIV-uh-kane)
A drug used to relieve pain by blocking signals at nerve endings. It is being studied in the relief of pain following surgery for cancer. It is a type of local anesthetic. Also called bupivacaine hydrochloride, Marcaine, and Sensorcaine.

bupivacaine hydrochloride  (byoo-PIV-uh-kane HY-droh-KLOR-ide)
A drug used to relieve pain by blocking signals at nerve endings. It is being studied in the relief of pain following surgery for cancer. It is a type of local anesthetic. Also called bupivacaine, Marcaine, and Sensorcaine.

bupropion  (byoo-PRO-pee-ON)
A substance that is used to treat depression, and to help people quit smoking. It belongs to the family of drugs called antidepressants.

burdock  
A plant whose seeds and root have been used in some cultures to treat certain medical problems. It may have antioxidant effects. The scientific name is Arctium lappa. Also called happy major and lappa.

Burkitt leukemia  (BER-kit loo-KEE-mee-uh)
A rare, fast-growing type of leukemia (blood cancer) in which too many white blood cells called B lymphocytes form in the blood and bone marrow. It may start in the lymph nodes as Burkitt lymphoma and then spread to the blood and bone marrow, or it may start in the blood and bone marrow without involvement of the lymph nodes. Both Burkitt leukemia and Burkitt lymphoma have been linked to infection with the Epstein-Barr virus.

Burkitt lymphoma  (BER-kit lim-FOH-muh)
An aggressive (fast-growing) type of B-cell non-Hodgkin lymphoma that occurs most often in children and young adults. The disease may affect the jaw, central nervous system, bowel, kidneys, ovaries, or other organs. There are three main types of Burkitt lymphoma (sporadic, endemic, and immunodeficiency related). Sporadic Burkitt lymphoma occurs throughout the world, and endemic Burkitt lymphoma occurs in Africa. Immunodeficiency-related Burkitt lymphoma is most often seen in AIDS patients.

burr hole  
A small opening in the skull made with a surgical drill.

bursitis  (ber-SY-tis)
Inflammation (swelling, pain, and warmth) of a bursa. A bursa is a flat, fluid-filled sac found between a bone and a tendon or muscle. It forms a cushion to help the tendon or muscle slide smoothly over the bone. Bursitis may be caused by long-term overuse, trauma, rheumatoid arthritis, gout, or infection. It usually affects the shoulder, knee, elbow, hip, or foot.

buserelin  
An anticancer drug that belongs to the family of drugs called gonadotropin-releasing hormones. In prostate cancer therapy, buserelin blocks the production of testosterone in the testicles.

buspirone  (byoo-SPY-rone)
A drug that is used to treat certain anxiety disorders. It belongs to the family of drugs called antianxiety agents.

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

buthionine sulfoximine  
A drug that may help prevent resistance to some anticancer drugs.

bypass  
A surgical procedure in which the doctor creates a new pathway for the flow of body fluids.

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Department of Health and Human Services National Institutes of Health USA.gov