Glossary

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A

Adenocarcinoma

Cancer that begins in cells that line certain internal organs and that have gland-like (secretory) properties.

Adenocarcinomas

Cancer that begins in cells that line certain internal organs and that have gland-like (secretory) properties.

Adjuvant therapy

Additional cancer treatment given after the primary treatment to lower the risk that the cancer will come back. Adjuvant therapy may include chemotherapy, radiation therapy, hormone therapy, targeted therapy, or biological therapy.

Androgen deprivation

Treatment to suppress or block the production or action of male hormones. This is done by having the testicles removed, by taking female sex hormones, or by taking drugs called antiandrogens. Also called androgen ablation and androgen suppression.

Androgen-deprivation

Treatment to suppress or block the production or action of male hormones. This is done by having the testicles removed, by taking female sex hormones, or by taking drugs called antiandrogens. Also called androgen ablation and androgen suppression.

Angiogenesis

Blood vessel formation. Tumor angiogenesis is the growth of new blood vessels that tumors need to grow. This process is caused by the release of chemicals by the tumor and by host cells near the tumor.

Antibody drugs

(Antibody therapy) Treatment with an antibody, a substance that can directly kill specific tumor cells or stimulate the immune system to kill tumor cells.

Antibody therapy

Treatment with an antibody, a substance that can directly kill specific tumor cells or stimulate the immune system to kill tumor cells.

Aromatase inhibitor

A drug that prevents the formation of estradiol, a female hormone, by interfering with an aromatase enzyme. Aromatase inhibitors are used as a type of hormone therapy for postmenopausal women who have hormonedependent breast cancer.

B

Biologic drug

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.

Biomarker

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.

Biopsy

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.

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.

BRCA1

A gene on chromosome 17 that normally helps to suppress cell growth. A person who inherits certain mutations (changes) in a BRCA1 gene has a higher risk of getting breast, ovarian, prostate, and other types of cancer.

BRCA2

A gene on chromosome 13 that normally helps to suppress cell growth. A person who inherits certain mutations (changes) in a BRCA2 gene has a higher risk of getting breast, ovarian, prostate, and other types of cancer.

C

Cell line

A perpetuating strain of cells grown in laboratory culture.

Chromosome

Discrete physical structures inside a cell nucleus that consist of proteins and DNA organized into genes.

Colonoscopy

Examination of the inside of the colon using a colonoscope, inserted into the rectum. A colonoscope is a thin, tube-like instrument with a light and a lens for viewing. Epidemiology: The study of the patterns, causes, and control of disease in groups of people.

CT scan

A procedure that uses a computer linked to an x-ray machine to make a series of detailed pictures of areas inside the body. The pictures are taken from different angles and are used to create 3-dimensional (3-D) views of tissues and organs.

D

DNA

The molecules inside cells that carry genetic information and pass it from one generation to the next. Also called deoxyribonucleic acid.

DNA methylation pattern

(Epigenetic alteration) A heritable change that does not affect the DNA sequence but results in a change in gene expression. Examples include promoter methylation and histone modifications. These changes can affect a person’s risk of disease and may be passed from parents to their children.

E

EGFR

The protein found on the surface of some cells and to which epidermal growth factor binds, causing the cells to divide. It is found at abnormally high levels on the surface of many types of cancer cells, so these cells may divide excessively in the presence of epidermal growth factor. Also called epidermal growth factor receptor, ErbB1, and HER1.

Epigenetic alteration

A heritable change that does not affect the DNA sequence but results in a change in gene expression. Examples include promoter methylation and histone modifications. These changes can affect a person’s risk of disease and may be passed from parents to their children.

Epigenetic changes

(Epigenetic alteration) A heritable change that does not affect the DNA sequence but results in a change in gene expression. Examples include promoter methylation and histone modifications. These changes can affect a person’s risk of disease and may be passed from parents to their children.

Estrogen

A type of hormone made by the body that helps develop and maintain female sex characteristics and the growth of long bones.

Estrogen receptor (ER) –positive

Describes cells that have a receptor protein that binds the hormone estrogen. Cancer cells that are estrogen receptor positive may need estrogen to grow, and may stop growing or die when treated with substances that block the binding and actions of estrogen. Also called ER+.

Estrogen receptor-positive

Describes cells that have a receptor protein that binds the hormone estrogen. Cancer cells that are estrogen receptor positive may need estrogen to grow, and may stop growing or die when treated with substances that block the binding and actions of estrogen. Also called ER+.

F

False-positive finding

A test result that indicates that a person has a specific disease or condition when the person actually does not have the disease or condition. Flexible sigmoidoscopy: Examination of the lower colon using a sigmoidoscope, inserted into the rectum. A sigmoidoscope is a thin, tube-like instrument with a light and a lens for viewing.

G

Gastroesophageal junction

The place where the esophagus is connected to the stomach.

Gene expression

The process by which a gene gets turned on in a cell to make RNA and proteins. Gene expression may be measured by looking at the RNA, or the protein made from the RNA, or what the protein does in a cell.

Gene therapy

A type of experimental treatment in which foreign genetic material (DNA or RNA) is inserted into a person’s cells to prevent or fight disease. Gene therapy is being studied in the treatment of certain types of cancer. Gene copy number: Refers to the genetic trait involving the number of copies of a particular gene present in the genome of an individual. Copy number variants account for a significant proportion of the genetic variation between individuals.

Gene transcript

An RNA copy of a sequence of DNA that is a gene.

Genomic profile

Information about all the genes in an organism, including variations, gene expression, and the way those genes interact with each other and with the environment. A genomic profile may be used to discover why some people get certain diseases while other people do not, or why people respond differently to the same drug.

Genomic profiling

(Genomic profile) Information about all the genes in an organism, including variations, gene expression, and the way those genes interact with each other and with the environment. A genomic profile may be used to discover why some people get certain diseases while other people do not, or why people respond differently to the same drug.

H

HER2-positive

Describes cancer cells that have too much of a protein called HER2 on their surface. In normal cells, HER2 helps to control cell growth. When it is made in larger than normal amounts by cancer cells, the cells may grow more quickly and be more likely to spread to other parts of the body. Checking to see if a cancer is HER2 positive may help plan treatment, which may include drugs that kill HER2 positive cancer cells.

Hormone therapy

Treatment that adds, blocks, or removes hormones. To slow or stop the growth of certain cancers (such as prostate and breast cancer), synthetic hormones or other drugs may be given to block the body’s natural hormones. Incidence: The number of new cases of a disease diagnosed each year.

I

Immune checkpoint inhibitor

A type of drug that blocks certain proteins made by some types of immune system cells, such as T cells, and some cancer cells. These proteins help keep immune responses in check and can keep T cells from killing cancer cells. When these proteins are blocked, the “brakes” on the immune system are released and T cells are able to kill cancer cells better.

Incidence

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

K

Kinase

A type of enzyme (a protein that speeds up chemical reactions in the body) that adds chemicals called phosphates to other molecules, such as sugars or proteins. This may cause other molecules in the cell to become either active or inactive. Kinases are a part of many cell processes. Some cancer treatments target certain kinases that are linked to cancer.

Kinases

A type of enzyme (a protein that speeds up chemical reactions in the body) that adds chemicals called phosphates to other molecules, such as sugars or proteins. This may cause other molecules in the cell to become either active or inactive. Kinases are a part of many cell processes. Some cancer treatments target certain kinases that are linked to cancer.

KRAS gene

A gene that may cause cancer when it is mutated (changed). The KRAS gene makes the KRAS protein, which is involved in cell signaling pathways, cell growth, and apoptosis (cell death). Agents that block the activity of the mutated KRAS gene or its protein may stop the growth of cancer.

M

Maintenance treatment

Treatment that is given to help keep cancer from coming back after it has disappeared following the initial therapy. It may include treatment with drugs, vaccines, or antibodies that kill cancer cells, and it may be given for a long time.

Marker

(Biomarker) 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.

Markers

(Biomarker) 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.

Metastatic

Having to do with metastasis, which is the spread of cancer from the primary site (place where it started) to other places in the body.

Molecular pathway

A series of actions among molecules in a cell that leads to a certain end point or cell function.

Mortality

Mortality refers to the death rate, or the number of deaths in a certain group of people in a certain period of time.

mTOR

A protein that helps control several cell functions, including cell division and survival, and binds to rapamycin and other drugs. mTOR may be more active in some types of cancer cells than it is in normal cells. Blocking mTOR may cause the cancer cells to die. It is a type of serine/threonine protein kinase. Also called mammalian target of rapamycin.

Mutation

Any change in the DNA sequence of a cell. Mutations may be caused by mistakes during cell division, or they may be caused by exposure to DNA-damaging agents in the environment. Mutations can be harmful, beneficial, or have no effect. If they occur in cells that make eggs or sperm, they can be inherited; if mutations occur in other types of cells, they are not inherited. Certain mutations may lead to cancer or other diseases.

N

Neoadjuvant therapy

Treatment given as a first step to shrink a tumor before the main treatment, which is usually surgery, is given. Examples of neoadjuvant therapy include chemotherapy, radiation therapy, and hormone therapy.

O

Oncogene

A gene that is a mutated (changed) form of a gene involved in normal cell growth. Oncogenes may cause the growth of cancer cells. Mutations in genes that become oncogenes can be inherited or caused by being exposed to substances in the environment that cause cancer.

Oncogenes

A gene that is a mutated (changed) form of a gene involved in normal cell growth. Oncogenes may cause the growth of cancer cells. Mutations in genes that become oncogenes can be inherited or caused by being exposed to substances in the environment that cause cancer.

Overall survival

The length of time from either the date of diagnosis or the start of treatment for a disease, such as cancer, that patients diagnosed with the disease are still alive. In a clinical trial, measuring the overall survival is one way to see how well a new treatment works.

Overall survival rate

The percentage of people in a study or treatment group who are still alive for a certain period of time after they were diagnosed with or started treatment for a disease, such as cancer. The overall survival rate is often stated as a five-year survival rate, which is the percentage of people in a study or treatment group who are alive five years after their diagnosis or the start of treatment.

P

Palliative care

Care given to improve the quality of life of patients who have a serious or life-threatening disease. The goal of palliative care is to prevent or treat as early as possible the symptoms of a disease, side effects caused by treatment of a disease, and psychological, social, and spiritual problems related to a disease or its treatment. Also called comfort care, supportive care, and symptom management.

PARP

A type of enzyme involved in many functions of the cell, including the repair of DNA damage. DNA damage may be caused by normal cell actions, UV light, some anticancer drugs, and radiation used to treat cancer. Inhibitors of one enzyme, PARP-1, are being studied in the treatment of cancer. Also called poly (ADP-ribose) polymerase.

Pathway

(Molecular pathway) A series of actions among molecules in a cell that leads to a certain end point or cell function.

Pathways

(Molecular pathway) A series of actions among molecules in a cell that leads to a certain end point or cell function.

Personalized care

(Personalized medicine) A form of medicine that uses information about a person’s genes, proteins, and environment to prevent, diagnose, and treat disease. Also called precision medicine.

Personalized medicine

A form of medicine that uses information about a person’s genes, proteins, and environment to prevent, diagnose, and treat disease. Also called precision medicine.

PET scan

A procedure in which a small amount of radioactive glucose (sugar) is injected into a vein, and a scanner is used to make detailed, computerized pictures of areas inside the body where the glucose is taken up. Because cancer cells often take up more glucose than normal cells, the pictures can be used to find cancer cells in the body. Also called positron emission tomography scan.

Platinum

A metal that is an important component of some anticancer drugs, such as cisplatin and carboplatin.

Progression-free survival

The length of time during and after the treatment of a disease, such as cancer, that a patient lives with the disease but it does not get worse. In a clinical trial, measuring the progression-free survival is one way to see how well a new treatment works. Also called PFS.

Prostate-specific antigen (PSA)

A protein made by the prostate gland and found in the blood. PSA blood levels may be higher than normal in men who have prostate cancer, benign prostatic hyperplasia (BPH), or infection or inflammation of the prostate gland. Also called prostatespecific antigen.

Q

QOL

(Quality of Life) The overall enjoyment of life. Many clinical trials assess the effects of cancer and its treatment on the quality of life. These studies measure aspects of an individual’s sense of well-being and ability to carry out various activities.

Quality of life

The overall enjoyment of life. Many clinical trials assess the effects of cancer and its treatment on the quality of life. These studies measure aspects of an individual’s sense of well-being and ability to carry out various activities.

R

Radioiodine

A radioactive form of iodine, often used for imaging tests or to treat an overactive thyroid, thyroid cancer, and certain other cancers. To treat thyroid cancer, the patient takes a large dose of radioactive iodine, which kills thyroid cells.

Radiopharmaceutical

A drug that contains a radioactive substance and is used to diagnose or treat disease, including cancer. Also called radioactive drug.

Randomization

When referring to an experiment or clinical trial, the process by which animal or human subjects are assigned by chance to separate groups that compare different treatments or other interventions. Randomization gives each participant an equal chance of being assigned to any of the groups.

Receptor

A molecule inside or on the surface of a cell that binds to a specific substance and causes a specific effect in the cell.

Resistant cancer

Cancer that does not respond to treatment. The cancer may be resistant at the beginning of treatment, or it may become resistant during treatment. Also called refractory cancer.

Response

In medicine, an improvement related to treatment.

Responses

In medicine, an improvement related to treatment.

S

Screening

Checking for disease when there are no symptoms.

Squamous cell carcinoma

Cancer that begins in squamous cells, which are thin, flat cells that look like fish scales. Squamous cells are found in the tissue that forms the surface of the skin, the lining of the hollow organs of the body, and the passages of the respiratory and digestive tracts.

Stem cell

A cell from which other types of cells develop. For example, blood cells develop from blood-forming stem cells.

Stem-cell transplantation

A method of replacing immature blood-forming cells in the bone marrow that have been destroyed by drugs, radiation, or disease.

Supportive care

Care given to improve the quality of life of patients who have a serious or life-threatening disease. The goal of supportive care is to prevent or treat as early as possible the symptoms of a disease, side effects caused by treatment of a disease, and psychological, social, and spiritual problems related to a disease or its treatment. Also called comfort care, palliative care, and symptom management.

T

Targeted drug

(Targeted therapy) A type of treatment that uses drugs or other substances, such as monoclonal antibodies, to identify and attack specific cancer cells. Targeted therapy may have fewer side effects than other types of cancer treatments.

Targeted drugs

(Targeted therapy) A type of treatment that uses drugs or other substances, such as monoclonal antibodies, to identify and attack specific cancer cells. Targeted therapy may have fewer side effects than other types of cancer treatments.

Targeted therapies

A type of treatment that uses drugs or other substances, such as monoclonal antibodies, to identify and attack specific cancer cells. Targeted therapy may have fewer side effects than other types of cancer treatments.

Targeted therapy

A type of treatment that uses drugs or other substances, such as monoclonal antibodies, to identify and attack specific cancer cells. Targeted therapy may have fewer side effects than other types of cancer treatments.

TKI

(Tyrosine kinase inhibitor) A drug that interferes with cell communication and growth and may prevent tumor growth. Some tyrosine kinase inhibitors are used to treat cancer.

TKIs

(Tyrosine kinase inhibitor) A drug that interferes with cell communication and growth and may prevent tumor growth. Some tyrosine kinase inhibitors are used to treat cancer.

Tyrosine kinase inhibitor (TKI)

A drug that interferes with cell communication and growth and may prevent tumor growth. Some tyrosine kinase inhibitors are used to treat cancer.

Tyrosine kinase inhibitors

A drug that interferes with cell communication and growth and may prevent tumor growth. Some tyrosine kinase inhibitors are used to treat cancer.

V

Vaccine

A substance or group of substances meant to cause the immune system to respond to a tumor or to microorganisms, such as bacteria or viruses. A vaccine can help the body recognize and destroy cancer cells or microorganisms.