Glossary
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Glossary of Terms

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3D mammogram

A type of mammogram. During a 3D mammogram, a digital camera moves over the breast, taking multiple pictures from different angles and generating a series of images that give a more complete, layer-by-layer picture of the breast.  

See also breast tomosynthesis. 

Abiraterone

Abiraterone is a drug used to treat prostate cancer. It is also known by the brand name Zytiga.

Absolute risk

A statistical term that describes the risks for an event to occur over time. Absolute risk is reported as percentage over time. For example, the average woman has an absolute risk for breast cancer of 12.5% by age 80. 

ACE inhibitors

A type of blood pressure medication. 

Adenocarcinoma

A cancer that develops in the cells that line some internal organs. 

Adenoma

A type of growth that is not cancer, like a polyp in the colon. Some adenomas are precancerous and can become cancer if left in the body.

Adjuvant

Advuvant therapy is given to people with early-stage cancer after the tumor is removed, when there is no longer evidence of disease. Adjuvant therapy is used to treat any microscopic cancer cells that may still be somewhere in the body after the cancer is removed.

Adjuvant chemotherapy

Adjuvant chemotherapy refers to chemotherapy that is given to people with early-stage cancer after the tumor is removed, when there is no longer evidence of disease. Adjuvant chemotherapy is used to treat any microscopic or undetected cancer cells that may still be somewhere in the body after the cancer is removed.

Adnexal

Adnexal refers to the area in the pelvis that includes the ovaries, fallopian tubes and tissue that surrounds them. 

Advanced-stage

Stage is a term used to describe how much a cancer has spread. Cancers are staged from stage 0 (preinvasive cancer) to stage 4. The lower the number, the less the cancer has spread. Advanced-stage cancers usually refer to stage 4 or metastatic cancers, which have spread to other organs from the original cancer.  

See also late-stage or metastatic cancer.

Adverse event

Any harmful side effect caused by a drug or other medical intervention.

Androgen deprivation therapy

A type of hormone therapy used to treat prostate cancer. Androgen deprivation therapy blocks the production or action of male hormones for treatment of advanced prostate cancer. Also known as ADT.

Angiogenesis

Angiogenesis refers to the formation of new blood vessels from already existing blood vessels. In cancer this usually refers to a process where tumors form new blood vessels as they grow. 

Medications that block angiogenesis are known as angiogenesis inhibitors or anti-angiogenesis agents. Examples include Bevacizumab (Avastin) and Everolimus (Affinitor). 

Ashkenazi Jewish

Jewish people from Eastern Europe are considered Ashkenazi Jewish. Ashkenazi Jewish people are 10 times more likely to have an inherited BRCA1 or BRCA2 mutation than people who are not of Eastern European Jewish descent. There are 3 common BRCA mutations found in Ashkenazi Jewish mutations. These three mutations are called founder mutations.

ATM

ATM is the name of a gene linked to cancer. Inherited mutations in ATM increase the risk for female breast, pancreatic, prostate and possibly other cancers and can cause cancer to run in families.

BARD1

BARD1 is a gene found on chromosome 2. Mutations in BARD1 increase the risk for female breast cancer and possibly other cancers. 

BART testing

BART stands for BracAnalysis Rearrangement Test. This is an expanded panel looking for mutations in BRCA 1 and BRCA 2 that are not found in Myriad's "comprehensive" Bracanalysis test. BART looks for specific mutations known as large rearrangements. Myriad charges an additional $700 for BART testing.

Bilateral

On both sides of the body. For instance, 'bilateral mastectomies' means the removal of both breasts.

Bilateral prophylactic mastectomy

Surgical removal of both breasts in order to lower the risk for cancer. 

Biomarker

A chemical in the body that can be measured. Doctors sometimes run tests to measure biomarker levels to diagnose or track a condition. CA125 is an example of a biomarker that can be elevated in women with ovarian cancer. 

Biomarker test

Biomarker tests measure chemicals in the body to diagnose or track a condition. CA125 is an example of a biomarker test that is sometimes used to diagnose or track ovarian cancer. 

BPM

Bilateral preventive mastectomy. Surgical removal of both breasts in order to lower the risk for cancer.

BRCA

BRCA refers to two genes BRCA1 and BRCA2. Mutations in these genes cause an increased risk for breast, ovarian, prostate, pancreatic, and melanoma cancers. Although BRCA1 and BRCA2 are often referenced together, they are separate genes. Mutations in BRCA1 and BRCA2 cause slightly different risks for different cancers. 

Also see BRCA1, BRCA2 and HBOC.

BRCA1

BRCA1 is the name of a gene linked to cancer. Inherited mutations in BRCA1 increase the risk for breast (male and female), ovarian, pancreatic, prostate and possibly other cancers and can cause cancer to run in families.

BRCA2

BRCA2 is the name of a gene linked to cancer. Inherited mutations in BRCA2 increase the risk for breast (male and female), ovarian, pancreatic, prostate, melanoma and possibly other cancers and can cause cancer to run in families. 

BRIP1

BRIP1 is a gene found on chromosome 17. Women who inherit one mutated copy of BRIP1 are at an increased risk of ovarian cancer. Research on the risk for other cancers for people with a mutation in BRIP1 is ongoing.

Inheriting two mutated copies of BRIP1, one from each parent, causes a rare blood disease known as Fanconi anemia in children.

BSE

Breast self-examination.

BSO

Bilateral salpingo-oophorectomy (removal of tubes and ovaries).

CA-125

A blood test used to detect signs of ovarian cancer or monitor response to treatment.

Carcinogen

A substance or environmental factor that has been shown to cause cancer. 

Carcinogens

Substances or environmental factors that have been shown to cause cancer. 

Castration-resistant prostate cancer

Prostate cancer that no longer responds to hormone therapy. Also called CRPC, or (in the case of metastatic cancer) MRCPC.

Castration-sensitive prostate cancer

Prostate cancer that still responds to hormone therapy. 

CBE

Clinical breast examination; a breast exam performed by a health-care professional.

CD8+ T cells

CD8+ T cells are white blood cells and are a part of the body's immune system that protects the body by killing cancer cells and infectious invaders.

CDC

Centers for Disease Control.

CDH1

CDH1 is the name of a gene that has been associated with hereditary diffuse gastric cancer syndrome. Mutations in CDH1 increase the risk of stomach cancer and breast cancer in women. CDH1 stands for "Cadherin-1."

CHEK2

CHEK2 is the name of a gene linked to cancer. Inherited mutations in CHEK2 increase the risk for breast cancer (in women and possibly in men), colorectal cancer and possibly prostate cancer. Mutations in CHEK2 can cause cancer to run in families. 

Chemoprevention

The use of medications to prevent cancer.

Cisgender

A person whose gender (male or female) is the same as the sex on their birth certificate. A person who is not transgender.  

Cisgender

People that identify with the same gender that was assigned to them at birth

Cognitive

Related to brain function and memory. 

Comorbidity

In cancer medicine, comorbidity refers to when a patient has another disease or condition that may complicate the treatment of their cancer. 

Companion diagnostic test

Companion diagnostic tests look for certain biomarkers or changes indicating that a tumor may respond well to a specific treatment known as a targeted therapy.

Confounder

A confounder is a factor that affects the relationship between variables being studied in research. For example, in the case of a study looking at breast cancer risk in young women, contraceptive use may be a confounder that needs to be studied.  

Contralateral breast cancer

Breast cancer in the other breast of patients who are already diagnosed with breast cancer. 

Cowden Syndrome

Cowden Syndrome is a condition caused by mutations in the PTEN gene. People with Cowden Syndrome have an increased risk for certain cancers, including female breast, uterine, thyroid, colon, kidney, melanoma, and possibly other cancers. 

Cowden syndrome is also associated with benign (noncancerous) tumors in the thyroid (goiter), uterus (fibroids), and gastrointestinal tract (polyps).  There can also be autism and autism-like features in PTEN families.

Also see PTEN

CT scan

CT scan stands for computed tomography scan. It is a type of imaging test in which a series of X-ray images are taken from different angles to create a 3-dimensional view of the body. CT scan images provide more-detailed information than single X-rays do.

ctDNA

Circulating tumor DNA (ctDNA) is a type of blood test that looks for mutations released from dying cancer cells. ctDNA tests may be used to find cancer, check for leftover cancer after treatment, monitor for a cancer recurrence or select the best therapy to treat a cancer based on tumor mutations. 

DCIS

Ductal carcinoma in situ, a noninvasive type of breast cancer.

Deleterious mutation

A harmful mutation. For example, a mutation that has been linked to an increased risk for cancer. 

Dermatologist

A type of doctor who focuses on conditions of the skin, hair and nails.

Diagnostic mammogram

A diagnostic mammogram is used to look more closely at breast changes to tell if they are cancer or benign. Diagnostic mammograms are different from screening mammograms, which are breast x-rays used to look for breast abnormalities or cancer in healthy women. 

Diagnostic mammograms

Diagnostic mammograms are used to look more closely at breast changes to tell if they are cancer or benign. Diagnostic mammograms are different from screening mammograms, which are breast x-rays used to look for breast abnormalities or cancer in healthy women. 

DIEP

Diep Inferior Epigastric Perforator: a type of breast flap reconstruction surgery.

dMMR

dMMR (Mismatch Repair-Deficient) is a biomarker found in tumors with mutations in genes that repair a certain type of DNA damage known as "mismatch repair." Tumors with mutations in mismatch repair genes may also be called MMR-D or Microsatellite Instability-High (MSI-H). dMMR tumors are frequently found in people with Lynch syndrome.

DNA

DNA stands for deoxyribonucleic acid. DNA is a chemical shaped like a very long ladder. DNA contains  instructions for the cells in your body on how they should function, grow, divide and die. Most cells in your body have the same DNA code. DNA has the following features:

  • it can make exact copies of itself. Before a cell divides into two cells, the DNA is copied so that new cells have the same DNA as their parent cell. 
  • DNA chains are organized into bundles known as genes.
  • DNA is used to make the proteins that allow your cells to work normally

Double-blinded

This is a type of clinical trial. In double-blinded studies, participants are randomly selected to one of the study groups. Neither the participants nor their doctors know which group they have been placed in and which agent or drug they are receiving. 

Double-blinded studies typically are also placebo-controlled studies. 

DSMB

Data Safety Monitoring Board. A committee made up of physicians, scientists, ethicists, statistical experts, and patient advocates all of who are independent from the research team. The DSMB looks at data from research studies in progress to further monitor safety and ensure no harm is done. The DSMB has the authority to pause or even stop a clinical trial if there is any concern about the safety of participants. 

Early-stage

Stage is a term used to describe how much a cancer has spread. Cancers are staged from stage 0 (preinvasive cancer) to stage 4. Although staging varies by cancer type, usually the lower the number, the less the cancer has spread. Early-stage cancers usually refer to stage 0-2.  

Enzalutamide

Enzalutamide is a drug used to treat prostate cancer. It is also known by the brand name Xtandi. 

EPCAM

EPCAM is the name of a gene linked to cancer. Inherited mutations in EPCAM are associated with Lynch syndrome, which can cause cancer to run in families. People with Lynch syndrome have an increased risk for colorectal, endometrial, ovarian, pancreatic and other cancers. 

Also see Lynch syndrome. 

ER/PR-negative

A type of breast cancer. Doctors use tests called tumor marker tests to help them choose the best breast cancer treatment. Two important tumor marker tests check to see if tumors respond to the hormones estrogen (ER) and progesterone (PR). Tumors that are negative for estrogen and progesterone are called ER/PR-negative.  

ER/PR-negative breast cancers are often treated with chemotherapy. They are not usually treated with hormone therapies such as tamoxifen and letrozole. 

ER/PR-positive

A type of breast cancer. Doctors use tests called tumor marker tests to help them choose the best breast cancer treatment. Two important tumor marker tests check to see if tumors respond to the hormones estrogen (ER) and progesterone (PR). Tumors that are positive for estrogen and progesterone are called ER/PR-positive.  

Hormone sensitive breast cancers are treated with hormone therapies such as tamoxifen and letrozole. 

ERT

Estrogen replacement therapy.

Estrogen

A type of hormone that helps develop and maintain female sex characteristics. Estrogens may be used in birth control or as part of hormone replacement therapy after menopause. 

Expanded access

Experimental drugs that have not yet been approved by the FDA are usually only available to patients enrolled in clinical trials. Under certain circumstances, some pharmaceutical companies may allow expanded access to a new drug that is not yet approved by the FDA. Expanded access is usually only available to patients who:

  • have advanced disease
  • do not qualify for a clinical trial

The decision to allow patients expanded access is up to the pharmaceutical company. 

Fallopian tube

The tube that connects the ovaries to the uterus. Eggs pass from the ovary, through the fallopian tube, to the uterus.

Fallopian tubes

The tubes that connect each ovary to the uterus. Eggs released from the ovaries pass through the fallopian tubes to get to the uterus.

False negative

When a test comes back normal but turns out to be wrong. For example, a normal mammogram that doesn't find a cancer in the breast.

False positive

When a test comes back abnormal but turns out to be wrong. For example, a positive mammogram that turns out not to be cancer.

FDA

Food and Drug Administration. FDA is a federal agency of the United States Department of Health and Human Services whose role is to regulate the safety, approval, labeling, and marketing of medications and devices. 

Fimbria

The part of the fallopian tube closest to the ovary.

First-degree relative

A first-degree relative refers to any of the following blood relatives: mother, father, sister, brother, son or daughter. 

First-line

First-line treatment or therapy is the first treatment given after cancer is diagnosed.

Flap

A type of breast reconstruction using the body's own tissue.

FNA

Fine needle aspirate (a technique for sampling breast tissue by placing a needle into the breast and removing cells).

Founder mutation

A gene mutation that is found with high frequency in certain ethnicities or descendants of people from specific geographic areas.

Gastroenterologist

A doctor who specializes in treating problems with the digestive tract (esophagus, stomach, intestines, colon, rectum, gall bladder, bile duct, liver and pancreas). 

Gender-affirming care

Gender-affirming care refers to medical care given to support an individual’s gender when it is different than the gender they were assigned at birth. Gender-affirming care may include medication, surgery and mental health care. 

Genomic alteration

A genomic alteration is a mutation or biomarker found in some cancers. Some treatments (called targeted therapies) work best on cancers that have a certain biomarker or mutation. 

Genomic test

Genomic tests look at DNA mutations within a tumor. These tests are done on tumor tissue obtained by biopsy. Genomic tests are often performed to see if a tumor is likely to respond to a particular treatment or to determine the likelihood that cancer will recur.

Genomic testing

Genomic testing looks at DNA mutations within a tumor. These tests are done on tumor tissue obtained by biopsy. Genomic tests are often performed to see if a tumor is likely to respond to a particular treatment or to determine the likelihood that cancer will recur.

Genomic variant

A genomic variant is a mutation or biomarker found in some cancers. Some treatments (called targeted therapies) work best on cancers that have a certain biomarker or mutation. 

Germline mutation

Another name for an inherited mutation linked to a disease, like cancer. Examples of germline mutations include BRCA1, BRCA2, PALB2, ATM and others. 

GINA

Genetic Information Nondiscrimination Act. A federal law in the United States that prohibits discrimination by health insurance companies and employers based on genetic information.

Gyn/onc

Gynecologic-oncologist, an expert in treating gynecologic malignancies.

HBOC

Hereditary Breast and Ovarian Cancer Syndrome. This refers to genetic mutations in certain genes that increase the risk for breast, ovarian and other cancers, such as pancreatic, prostate, and melanoma. The most common gene mutations associated with HBOC are BRCA1 and BRCA2. Other genes, including PALB2, PTEN, ATM, CHEK2 may also be associated with this syndrome. 

Health disparities

Increases in disease burden and worse health outcomes experienced by people who belong to disadvantaged racial, ethnic, gender and other groups, and communities. 

HER2

HER2, also known as HER2neu is a type of receptor found on breast cancer tumor cells. Doctors use tests called tumor marker tests to help them choose the best breast cancer treatment. Tumors that test positive for HER2 are called HER2-positive. Tumors that test negative for HER2 are called HER2-negative. 

HER2-negative

A type of cancer marker test. Doctors test cancers for a protein called HER2 to see if the cancers are likely to respond a type of treatment known as "anti-HER2 therapy." Cancers that test negatie for the HER2 marker are called HER2-negative. These cancers don't respond to anti-HER2 therapy. 

HER2-positive

A type of breast cancer. Doctors use tests called tumor marker tests to help them choose the best breast cancer treatment. An important tumor marker test looks at whether a tumor has a receptor known as HER2neu (HER2). Tumors that are HER2-positive are often treated with a targeted therapies such as Herceptin or Perjeta. 

Hereditary cancer

Hereditary cancers or inherited cancers are caused by a genetic mutations that can be passed from one generation to the next; mothers and fathers can pass these mutations to sons and daughters.

A person who inherits a genetic mutation from their parent will have a higher lifetime risk for certain types of cancer. A family with hereditary cancer may have many family members who have been diagnosed. 

Many different genes have been identified that can increase the risk for different types of cancer. Genetic testing on blood or saliva can tell if a person has inherited a gene mutation that increases cancer risk. 

HNPCC

HNPCC stands for Hereditary Nonpolyposis Colon Cancer (HNPCC). This is a type of cancer syndrome that is usually referred to as Lynch Syndrome. 

Homologous Recombination

Homologous recombination is a method that normal cells use to repair damage to DNA. Some types of cancers lack the ability to repair DNA damage using this method. These cancers are considered Homologous Recombination Deficient. 

Homologous Recombination Deficiency

Homologous Recombination Deficiency. Homologous recombination is a method that normal cells use to repair damage to DNA. Cells with homologous recombination deficiency have lost their ability to repair DNA damage using this method of repair. People with certain inherited mutations like BRCA1, BRCA2 or PALB2 tend to develop cancers that are homologous recombination deficient. This deficiency in repair of DNA damage makes cancers caused by these mutations more responsive to certain types of cancer treatment such as platinum chemotherapy and PARP inhibitors. 

Also see HRD.

HOXB13

HOXB13 is the name of a gene linked to prostate cancer. Inherited mutations in HOXB13 increase the risk for prostate cancer and can cause cancer to run in families.  

HR

Homologous Recombination. Homologous recombination is a method that normal cells use to repair damage to DNA. Some types of cancers lack the ability to repair DNA damage using this method. These cancers are considered Homologous Recombination Deficient. 

HR-positive

HR-positive means "hormone receptor positive." This is a subtype of cancer that may grow faster when exposed to hormones such as estrogen and progesterone. HR-positive cancers are often treated with drugs that block or reduce estrogen. 

HRD

Homologous Recombination Deficiency. Homologous recombination is a method that normal cells use to repair damage to DNA. Cells with homologous recombination deficiency have lost their ability to repair DNA damage using this method of repair. People with certain inherited mutations like BRCA1, BRCA2 or PALB2 tend to develop cancers that are homologous recombination deficient. This deficiency in repair of DNA damage makes cancers caused by these mutations more responsive to certain types of cancer treatment such as platinum chemotherapy and PARP inhibitors. 

HRT

Hormone replacement therapy.

Hyst

Hysterectomy, or removal of the uterus.

Immunotherapy

A type of cancer treatment that helps the body's immune system detect and attack cancer cells. 

Inherited cancer

Hereditary cancers or inherited cancers are caused by a genetic mutations that can be passed from one generation to the next; mothers and fathers can pass these mutations to sons and daughters.

A person who inherits a genetic mutation from their parent will have a higher lifetime risk for certain types of cancer. A family with hereditary cancer may have many family members who have been diagnosed. 

Many different genes have been identified that can increase the risk for different types of cancer. Genetic testing on blood or saliva can tell if a person has inherited a gene mutation that increases cancer risk. 

Inherited mutation

Inherited mutations are mutations that can be passed down from parents to their children. Inherited mutations in BRCA1, BRCA2 or the Lynch syndrome genes are associated with a very high risk for cancer and can cause cancer to run in families. 

Ipsilateral breast cancer

When someone diagnosed with breast cancer develops a new cancer in the same breast as their first cancer diagnosis. 

IRB

Institutional Review Board. An IRB is a committee made up of researchers, health care providers and patients who review research study designs involving human participants to make sure they are ethical and safe. IRBs review the way a study will be conducted, and how it consents and recruits patients. Upon review of the study protocol, an IRB can approve, require modification or disapprove. 

Most large hospitals and cancer centers have their own IRB which reviews all research conducted at that institution. 

IVF

In Vitro Fertilization: a fertility treatment where the woman's eggs are removed and fertilized in a test tube.

Late-stage

Stage is a term used to describe how much a cancer has spread. Cancers are staged from stage 0 (preinvasive cancer) to stage 4. Although staging varies by cancer type, usually the lower the number, the less the cancer has spread. Late-stage cancers usually refer to stage 4 or metastatic cancers.  

See also advanced-stage or metastatic cancer.

LAVH

Laparoscopic-assisted vaginal hysterectomy.

LCIS

Lobular cancer in situ, a noninvasive change in breast tissue that can be a marker for breast cancer risk.

Li-Fraumeni Syndrome

Li Fraumeni syndrome is a condition caused by an inherited mutation in the TP53 gene.People with Li-Fraumeni Syndrome have an increased risk for many different types of young-onset cancers including breast, bone, adrenal and brain. 

Also see TP53.

Liquid biopsy

Liquid biopsies are a type of test that checks blood, urine or other body fluids for mutations or other abnormal products released from dying cancer cells. Tests for circulating tumor cells or for circulating tumor DNA (ctDNA) are types of liquid biopsy. 

Lumpectomy

A lumpectomy is a surgery that is performed to remove a lump in the breast often to diagnose or treat breast cancer. 

Lymph nodes

Lymph nodes are small organs found throughout the body that are part of the immune system. Lymph nodes help the filter infections and cancer cells from the body and house some immune cells. Lymph nodes can become enlarged when an infection occurs. Checking for cancer spread to the lymph nodes near a tumor is an important part of the cancer staging process.

Lymphedema

Lymphedema is condition where tissue swells because of water retention in certain parts of the body. Lymphedema is caused by damage to the lymphatic system, often due to surgery, radiation, or trauma. Lymphedema can cause limb swelling after cancer treatment or surgery. 

Lymphoma

A type of cancer that starts in cells of the immune system.

Lynch Syndrome

Lynch Syndrome refers to genetic mutations in certain genes that increase the risk for colon, uterine, ovarian, pancreatic and other cancers. The gene mutations associated with Lynch Syndrome are MLH1, MSH2, MSH6, PMS2, and EPCAM.

Lynch Syndrome is sometimes called by it's prior name Hereditary Nonpolyposis Colon Cancer (HNPCC).

Maintenance therapy

Maintenance therapy is a type of treatment that is given after initial standard treatment has been completed to try to keep the cancer from returning. 

Maintenance therapy can include different types of treatment including targeted therapies, hormonal therapies, or antibodies that kill cancer cells, and it may be given for a long time.

Mammogram

Mammograms are a type of x-ray used to look for abnormalities or cancer in the breast. 

Also known as mammography.

Mammography

Mammography is a type of x-ray used to look for abnormalities or cancer in the breast. 

Also known as mammograms.

Meta-analysis

A meta-analysis is a type of research that combines the data of several similar but separate scientific studies conducted in the past to look at outcomes across all the studies.   

Metastasis

An area where cancer has spread beyond the organ where the cancer began. 

Metastatic

Metastatic cancers are those that have spread beyond the organ where the cancer began to other organs. Metastatic cancers are also referred to as stage 4 cancers.

Also see staging.

Microsatellite instability

Microsatellite instability is a type of change in DNA that can occur in certain cells, including cancer cells. Tests for microsatellite instability can help identify tumors that may respond to immunotherapy. Microsatellite instability is common in tumors of people with Lynch syndrome. 

Mismatch repair deficiency

Mismatch repair deficiency (MMR) is caused by mutations (changes) in genes that fix DNA damage in cells. Testing a tumor for mismatch repair deficiency can help identify cancers that may respond to certain types of treatment. The genes associated with Lynch syndrome are involved in DNA mismatch repair and tumors in people with Lynch syndrome are MMR deficient.

MLH1

MLH1 is the name of a gene linked to cancer. Inherited mutations in MLH1 are associated with Lynch syndrome, which can cause cancer to run in families. People with Lynch syndrome have an increased risk for colorectal, endometrial, ovarian, pancreatic and other cancers. 

Also see Lynch syndrome. 

MMR-D

MMR-D (Mismatch Repair-Deficient) is a biomarker found in tumors with mutations in genes that repair a certain type of DNA damage known as "mismatch repair." Tumors with mutations in mismatch repair genes may also be called dMMR or Microsatellite Instability-High (MSI-H). MMR-D tumors are frequently found in people with Lynch syndrome.

morbidity

morbidity: the disease or medical problems associated with a disease or its treatment

MRI

Magnetic Resonance Imaging; a technique for looking for abnormalities such as cancer using magnetic fields. Breast MRI is typically recommended as a screening tool for breast cancer in high-risk women and is often used to follow up on a breast abnormality seen on mammogram.

MSH2

MSH2 is the name of a gene linked to cancer. Inherited mutations in MSH2 are associated with Lynch syndrome, which can cause cancer to run in families. People with Lynch syndrome have an increased risk for colorectal, endometrial, ovarian, pancreatic and other cancers. 

Also see Lynch syndrome. 

MSH6

MSH6 is the name of a gene linked to cancer. Inherited mutations in MSH6 are associated with Lynch syndrome, which can cause cancer to run in families. People with Lynch syndrome have an increased risk for colorectal, endometrial, ovarian, pancreatic and other cancers. 

Also see Lynch syndrome. 

MSI-High

MSI-High (or Microsatellite Instability-High) is a biomarker found in tumors with mutations in genes that repair a certain type of DNA damage known as "mismatch repair." MSI-H tumors are frequently found in people with Lynch syndrome. Tumors with mutations in mismatch repair genes may also be called "Mismatch Repair-Deficient" (MMR-D or dMMR). 

Multidisciplinary team

Healthcare professionals from different specialties who work together to provide patient care. Multidisciplinary teams may be used to treat more complicated cancer cases that require care from different types of experts. 

National Comprehensive Cancer Network (NCCN)

NCCN is an organization of leading cancer centers, which develops expert guidelines for cancer prevention, treatment and quality of life. NCCN updates their guidelines every year. 

NBN

NBN is a gene found on chromosome 8. A number of studies have shown that women who inherit a mutated copy of NBN from one parent are at increased risk of breast cancer and that men who inherit an NBN mutation are at increased risk for prostate cancer. Ongoing research is studying the types cancers and the extent of cancer risk associated with inheriting a mutation in NBN from one parent.

Inheriting mutated copies of the NBN gene from both parents causes a rare childhood disease called Nijmegen Breakage Syndrome (NBS). Children with NBS experience slow growth, have difficulty fighting infections, and are at increased risk of childhood cancers.

Neoadjuvant

Treatment (such as chemotherapy) given before surgery to shrink a tumor. 

NF1

NF1 is a gene found on chromosome 17. People with a mutation in NF1 are at increased risk for tumors of the nervous system and rare tumors of the gastrointestinal system known as gastrointestinal stromal tumors (GIST). Women with NF1 mutations are also at increased risk for breast cancer before age 50. 

NIH

National Institutes of Health.

Niraparib

Niraparib is a type of cancer treatment known as a PARP inhibitor. Zejula is FDA approved for maintenance therapy in any woman with certain types of recurrent ovarian, fallopian tube or primary peritoneal cancer. 

Also see Zejula.

Non-randomized

Non-randomized is a term used in clinical trials to describe how patients are assigned to the different study groups or arms. In non-randomized studies participants may be assigned to a study arm based on factors such as patient or doctor choice, gene mutation, tumor markers or other factors.  

A non-randomized study is different from a randomized study where participants are placed into one of the study groups by chance. In randomized studies, neither patients nor the research doctor choose the group participants are placed in. 

NSAID

Non-steroidal anti-inflammatories. NSAIDS are a type of pain-reliever that also decreases inflammation. It includes drugs like aspirin, ibuprofen, and Aleve.

Olaparib

Olaparib is a type of cancer treatment known as a PARP inhibitor. It also goes by the brand name Lynparza.

OncoKB

OncoKB is a database developed by experts at Memorial Sloan Kettering. OncoKB allows users to search by cancer mutations and the different treatments which may be effective against them. 

Oophorectomy

Removal of the ovaries.

Also see risk reducing salpingo-oophorectomy or RRSO.

Open-label

Open-label is a term used in clinical trials to describe a type of study design. In an open-label study, all participating patients will know which intervention or medication they are receiving during the study.

An open-label study is different from a blinded study where neither the participant nor their doctor know which intervention or medication they are receiving during the study.   

Osteoporosis

Osteoporosis is a weakening of the bones that can make them more likely to break. Osteoporosis may be caused by aging, loss of hormones due to menopause, malnutrition, smoking or other factors. 

OVCA

Ovarian cancer.

Overdiagnosis

Overdiagnosis refers to the idea that routine screening for certain cancers may pick up early-stage, slow-growing cancers that will never cause a person harm even if the cancer goes untreated. Overdiagnosis implies that the treatment of the cancer may be more harmful than the cancer itself. 

PALB2

PALB2 is the name of a gene linked to cancer. Inherited mutations in PALB2 increase the risk for female breast, ovarian, pancreatic and possibly other cancers and can cause cancer to run in families.

Palliative care

Palliative care is a area of medicine focused on quality of life issues for patients and their families facing life-threatening illness.

PARP inhibitor

PARP inhibitors are a type of cancer treatment known as targeted therapy. 

PD-L1

PD-L1 stands for Programmed Death Ligand 1. PD-L1 is a protein made by some cancers, which allows them to escape the immune system. PD-L1 tricks the body's immune system into thinking the cancer cells are normal, causing the immune system to leave the cancer cells alone.

PDAC

Pancreatic ductal adenocarcinoma (PDAC) is the most common form of pancreatic cancer.

Personalized medicine

Personalized medicine (also known as "precision medicine") uses information about an individual’s genetic make-up to deliver the right screening, prevention, or treatment options at the right time to achieve the best medical outcome.

PET scan

PET scan stands for positron emission tomography scan. This is a type of imaging test that is used to locate cancer cells in the body.  

Peutz-Jeghers Syndrome

Peutz-Jeghers syndrome is a rare disorder that leads to increased risk of noncancerous growths and increased risk of certain cancers. It's caused by mutations in the gene STK11.

People with Peutz-Jeghers syndrome are at increased risk for breast, colon, pancreatic, stomach, ovarian, lung, intestinal, cervical and uterine cancers. 

People with Peutz-Jeghers syndrome also tend to develop noncancerous polyps in the stomach and intestine. Children with this syndrome often have dark spots in or near the mouth, eyes, nostrils and/or fingers.

PGD

Preimplantation Genetic Diagnosis (also known as Preimplantation Genetic Testing or PGT) is a medical procedure that allows people who carry a disease-causing hereditary mutation to have children who are free from the specific mutation that causes the disease.

Placebo

Placebos are harmless sugar pills that are made to look like a medication. They are sometimes used in clinical trials testing a new medication, these studies are known as placebo-controlled studies.

Placebo-controlled

Placebos are harmless sugar pills used in research in situations where there is no standard treatment. 

Placebo-controlled describes a type of clinical trial. In placebo-controlled trials patients are assigned to one of two or more groups. One group typically receives usual care, and the other receives usual care plus a placebo.  

Platinum sensitive

Platinum sensitive cancers respond to treatment with chemotherapy drugs that contain the metal platinum, such as cisplatin and carboplatin.

PM

Prophylactic mastectomy (or mastectomies).

PMS2

PMS2 is the name of a gene linked to cancer. Inherited mutations in PMS2 are associated with Lynch syndrome, which can cause cancer to run in families. People with Lynch syndrome have an increased risk for colorectal, endometrial, ovarian, pancreatic and other cancers. 

Also see Lynch syndrome. 

PMSA

PMSA stands for prostate-specific membrane antigen. PMSA is a protein found at low levels in normal prostate cells, and is found at high levels in prostate cancer cells. It is sometimes used as a biomarker to find prostate cancer recurrence. 

Polyps

Polyps are small growths found in the colon. Some polyps can turn into cancer if they are not removed. 

Pragmatic Clinical Trial

Pragmatic Clinical Trials are research studies that take place in clinical settings and usually compare two or more accepted treatment options to learn the long-term outcomes and help experts and patients determine which medical option is right for them. 

Precision medicine

Precision medicine (also known as "personalized medicine") uses information about an individual’s genetic make-up to deliver the right screening, prevention, or treatment options at the right time to achieve the best medical outcome.

Progestin

A type of hormone that helps the body during pregnancy. Progestins may be used in birth control or as part of hormone replacement therapy after menopause. 

progestogen

A progestogen is a molecule that acts like the hormone progesterone to a signal a pregnancy-like state. It may be used as part of hormone therapy. Progestogen can be natural or man-made. Other names for progestogen are progestagen, gestagen, or gestogen.

Proliferation gene signatures

A proliferation gene signature is a characteristic pattern of gene expression (some genes actively making RNA, other genes not making RNA) that occurs as a result of proliferation or growth of a tissue.

PROMIS

Patient-Reported Outcomes Measurement Information System refers to survey tools that are used within research to measure specific health, wellbeing and other types of outcomes.

Prospective

A type of research study that enrolls people and then follows them forward to record changes over time. By contrast, a "retrospective research study" looks back at the history of the people enrolled in the study to look at the effects of a factor on the disease being studied.

Prostate

The prostate is a small, walnut-size gland that is part of the male reproduction system. The prostate is located at the base of the penis, just below the bladder. It surrounds the urethra (the tube that carries urine and semen out of the body).

Prostate-specific membrane antigen

Prostate-specific membrane antigen (also known as PMSA) is a protein found at low levels in normal prostate cells, and is found at high levels in prostate cancer cells. It is sometimes used as a biomarker to find prostate cancer recurrence. 

PSA

PSA stands for "prostate specific antigen." It is a biomarker that can be measured in the blood to detect prostate cancer. High PSA levels may be caused by cancer or non-cancerous conditions of the prostate.

PTEN

PTEN is a gene found on chromosome 10. Mutations in PTEN increase the risk for certain cancers, including breast, uterine, thyroid, colon, kidney, melanoma and possibly other cancers. PTEN mutations may also cause Cowden Syndrome, which is also associated with benign (noncancerous) tumors in the thyroid (goiter), uterus (fibroids), and gastrointestinal tract (polyps).  There can also be an excess of autism and autism-like features in PTEN families.

Also see Cowden's Syndrome.

RAD50

RAD50 is a gene found on chromosome 5. Some studies have suggested that mutations in the RAD50 gene increase a woman’s risk of breast cancer. Ongoing research is exploring the extent of that risk, and whether or not a RAD50 mutation increases a person’s risk for other types of cancers.

RAD51C

RAD51C is a gene found on chromosome 17. Women who inherit one mutated copy of RAD51C are at an increased risk of ovarian cancer. Ongoing research is studying the extent of that risk, and whether or not inheriting a RAD51C mutation increases a person’s risk for other types cancers.

Inheriting two mutated copies of RAD51C, one from each parent, has been shown to cause a rare blood disease known as Fanconi anemia in children.  

RAD51D

RAD51D is a gene found on chromosome 17. Several studies have suggested that mutations in the RAD51D gene increase a woman’s risk of ovarian cancer, and possibly breast cancer as well. Ongoing research is exploring the extent of that risk, and whether or not a RAD51D mutation increases a person’s risk for other types of cancers.

Randomized

Randomized describes a type of clinical trial. In randomized trials patients are assigned to one of two or more groups. Participants are placed into one of the two study groups by chance. Neither patients nor the research doctor choose the group participants are placed in. 

Randomized clinical trial

Randomized clinical trial refers to a type of research study or clinical trial design. In a randomized study, participants are placed into one of the two study groups by chance. Neither patients nor their research doctor choose the group participants are placed in. 

Randomized controlled trial

Randomized controlled trial refers to a type of research study used to compare two or more groups of people who received different types of medical care to see if there is a difference in their outcomes. This type of study has the following features: 

  • Controlled refers to the groups of participants and what treatment they receive. In a controlled study there are at least two groups: a group that receives the intervention or treatment being tested and a group that receives usual care or no treatment. The group that receives usual care or no treatment is referred to as the control arm. The outcomes of people in the test group are compared against the outcomes of people in the control group to see which group does better. 
  • Randomized refers to how people are selected for the two or more groups being studied. In a randomized study, participants are placed into one of the two study groups by chance. Neither patients nor their research doctor choose the group participants are placed in. 

Randomized controlled trials are considered the ideal study design to test whether one treatment or intervention is better than another. 

RCT

Randomized controlled trial

Recall bias

Recall bias refers to errors that can happen in research that depends on participants' memory. 

Relative risk

Relative risk is a statistical term that compares the risks for an event or diagnosis between two different groups. Relative risk is reported as a fraction or percentage. For example, if a group has a relative risk of 3, their risk is 3 times that of the group they are being compared to.

Retrospective

A study that looks back at the history of people being studied to find similarities or differences in medical history or exposure and their effects on the disease being studied. By contrast, a "prospective research study" follows people forward to record changes over time. 

Revision

A type of plastic surgery which may be done as a follow-up to an earlier operation.

Risk reducing salpingo-oophorectomy

Surgical removal of healthy ovaries and fallopian tubes in order to lower the risk for cancer. 

RRSO

Risk-reducing salpingo-oophorectomy. This refers to removal of the fallopian tubes and ovaries to lower risk for ovarian cancer.

Rubraca

Rubraca is a type of cancer treatment known as a PARP inhibitor. Rucaparib is FDA approved to treat recurrent ovarian cancer in women with an inherited BRCA mutation or a somatic BRCA mutation within their tumor. 

Also see Rucaparib.

Rucaparib

Rucaparib is a type of cancer treatment known as a PARP inhibitor. Rucaparib is FDA approved to treat recurrent ovarian cancer in women with an inherited BRCA mutation or a somatic BRCA mutation within their tumor. 

Also see Rubraca.

Salpingectomy

Removal of the fallopian tubes.

Schema

A schema is a diagram that illustrates the design of a research study. Schemas often depict the following aspects of a study:

  • Description of the patients being enrolled in the study and eligibility
  • If there is more than one arm, a description of the different study arms
  • What intervention or treatment each group of participants will receive and the timeline
  • The outcomes being measured by the study
  • Additional study design features, e.g. randomization, crossover, and blinding

Screen-detected

Screen-detected cancers are those found during routine screenings such as mammograms.

Screening mammogram

A screening mammogram is a breast x-ray used to look for breast abnormalities or cancer in healthy women. Screening mammograms are different from diagnostic mammograms, which are used to look more closely at breast changes (such as breast lumps) to tell if they are cancer or benign. 

Screening mammograms

Screening mammograms are breast x-rays used to look for breast abnormalities or cancer in healthy women. Screening mammograms are different from diagnostic mammograms, which are used to look more closely at breast changes (such as breast lumps) to tell if they are cancer or benign. 

Screening mammography

Screening mammography is the use of breast x-rays to look for breast abnormalities or cancer in healthy women. Screening mammograms are different from diagnostic mammograms, which are used to look more closely at breast changes (such as breast lumps) to tell if they are cancer or benign. 

Second-degree relative

A second-degree relative refers to any of the following blood relatives: grandmother, grandfather, granddaughter, grandson, uncle, aunt, neice, nephew, half-sister or half-brother. 

SEER

The Surveillance, Epidemiology, and End Results (SEER) is a program of the National Cancer Institute. SEER is a database that collects information on cancer cases from various locations and sources throughout the United States. 

Sentinel node biopsy

Sentinel node biopsy is a procedure to looks at whether breast cancer cells have spread beyond the breast tissue. A blue dye or a radioactive tracer (or both) are injected into the breast before surgery to follow the lymph system from the tumor to the sentinel node. This allows the surgeon to find main lymph nodes that drain the breast and remove only one or two main lymph nodes. 

SHG

Saline sonohystogram.

Single nucleotide polymorphism

A single nucleotide polymorphism or SNP is a common variation in a single base-pair of normal DNA, where there are two or more equally acceptable nucleotides. 

SNP

SNP is an abbreviation of single nucleotide polymorphism. SNPs are common variations in a single base-pair of normal DNA, where there are two or more equally acceptable nucleotides.

Solid tumors

Cancers that arise from solid organs, for example, breast, colon, lung, ovary, pancreas, prostate, ovary, uterus.

Somatic mutation

A somatic mutation is a type of DNA change that is acquired rather than inherited. Somatic mutations from cancer cells may be found by testing tumors directly or through a type of test called liquid biopsy that checks blood, urine or other body fluids for mutations released from dying cancer cells. 

Somatic mutations

Somatic mutations are DNA mutations that are acquired rather than inherited. Somatic mutations are different from germline mutations, which are inherited from parents and present in each cell at birth. In cancer, somatic mutations can be discovered through testing a piece of the tumor (also known as genomic testing). Somatic mutations in cancer can provide clues for treatment approaches such as targeted therapy.

Sono

Sonogram (ultrasound).

Sporadic breast cancer

Sporadic breast cancer is breast cancer that occurs due to mutations that happen during a person's lifetime and not due to inherited mutations.

Sporadic mutation

A sporadic mutation is a mutation that occurs during a person's lifetime and is not inherited from a parent.

Stage

Stage is a term used to describe how much a cancer has spread. Cancers are staged from stage 0 (preinvasive cancer) to stage 4. Although staging varies by cancer type, usually the lower the number, the less the cancer has spread.

Staging

Staging refers to procedures used to determine if and how much cancer has spread. Cancers are staged from stage 0 (preinvasive cancer) to stage 4 (spread outside the initial tissue). Stage 4 cancer is also known as "metastatic cancer."

STK11

STK11 is a gene found on chromosome 19. Mutations in STK11 are associated with Peutz-Jeghers syndrome, a rare disorder that leads to increased risk of noncancerous growths and increased risk of certain cancers. 

People with STK11 mutations are at a greatly increased risk of:

breast cancer in women (up to 50% lifetime risk)
colon cancer (up to 39% lifetime risk)
pancreatic cancer (up to 36% lifetime risk)
stomach cancer (up to 29% lifetime risk)
ovarian cancer (up to 21% lifetime risk)
lung cancer (up to 17% lifetime risk)
small intestine cancer (up to 13% lifetime risk)
cervical cancer (up to 10% lifetime risk)
uterine cancer (up to 9% lifetime risk)

See also Peutz-Jeghers Syndrome 

Systemic therapy

Therapy that delivers treatments throughout the body. May be intravenous or pill form. Examples include chemotherapy, biologic therapy and hormone therapy.

Talazoparib

Talazoparib is a type of cancer treatment known as a PARP inhibitor. Talzenna is FDA approved to treat advanced or metastatic her2-negative breast cancer in people with an inherited BRCA1 or BRCA2 mutation. 

See also Talzenna.

Talzenna

Talzenna (talazoparib) is a type of cancer treatment known as a PARP inhibitor. Talzenna is FDA approved to treat advanced or metastatic her2-negative breast cancer in people with an inherited BRCA1 or BRCA2 mutation. 

See also talazoparib.

Targeted therapy

Targeted therapies are medications that are designed to kill only cancer cells while sparing normal cells. They tend to cause fewer side effects than chemotherapy drugs, which are more likely to kill healthy cells along with cancer cells.

TNBC

Triple-negative breast cancer. A type of breast cancer. Doctors use tests called tumor marker tests to help them choose the best breast cancer treatment. Three important tumor marker tests are Estrogen (ER), Progesterone (PR), and Her2. Tumors that test negative for ER, PR and HER2 are called triple-negative breast cancer. These breast cancers are often treated with chemotherapy. 

Tomosynthesis

Breast tomosynthesis, also known as 3-D mammography, is a form of digital mammography. During a 3-D mammogram, a digital camera moves over the breast, taking multiple pictures from different angles and generating a series of images that give a more complete, layer-by-layer picture of the breast.  

See also 3-D mammography.

Toxicity

A harmful side effect caused by a drug or other intervention. 

TP53

TP53 is a gene found on chromosome 17. Mutations in TP53 are associated with Li-Fraumeni syndrome. People with Li-Fraumeni Syndrome have an increased risk for many different types of young-onset cancers including breast, bone, adrenal and brain. 

Also see Li-Fraumeni Syndrome.

TRAM

TRAM is an abbreviation for Transverse rectus abdominous myocutaneous flap. This is a type of reconstructive surgery where fat and muscle from the abdomen are used to recreate breast tissue.

Transrectal Ultrasound

Transrectal ultrasound is a test that uses an ultrasound probe inserted into the rectum to measure the size of the prostate gland. Also called TRUS. 

Triple-negative breast cancer

A type of breast cancer. Doctors use tests called tumor marker tests to help them choose the best breast cancer treatment. Three important tumor marker tests are Estrogen (ER), Progesterone (PR), and HER2. Tumors that test negative for ER, PR and Her2 are called triple-negative breast cancer. These breast cancers are often treated with chemotherapy. 

TRUS

Transrectal ultrasound. TRUS is a test that uses an ultrasound probe inserted into the rectum to measure the size of the prostate gland. 

Tumor margin

The term tumor margin is used by pathologists to describe the area of normal tissue surrounding cancerous tissue removed during a biopsy.

Tumor mutational burden

Tumor mutational burden is a type of tumor test that measures the amount of DNA changes in cancer cells. Tumors with a very high number of mutations may respond well to certain treatments, for example immunotherapy. 

TVH

Total vaginal hysterectomy.

TVU

Transvaginal ultrasound.

U/S

Ultrasound; or ultrasonographic examination.

Ultrasound

Also known as a sonogram, ultrasound is a device that uses sound to see images of internal organs and look for abnormalities in the body. Ultrasounds are sometimes used along with other methods to diagnose breast, ovarian, and pancreatic, and prostate cancers. Ultrasounds may also be used to diagnose pregnancy or conditions such as heart disease.

Unblinding

Unblinding refers to a situation that can happen in double-blinded clinical trials. 

Unblinding is where participants in the study and their doctors are informed of which study group they were placed in. Unblinding may happen in specific circumstances including:

  • when the study is completed or if it is ended early
  • if the patient progresses
  • if the patient experiences a serious adverse event
  • if the patient withdraws

Not all studies allow unblinding. It is important for people considering participating in a clinical trial to find out what the study protocol is for unblinding. 

Urethra

The urethra is the tube that carries urine from the bladder to outside of the body. In men the urethra also carries semen. 

USPSTF

United States Preventive Services Task Force. A volunteer panel of experts who develop evidence-based guidelines for different areas of preventive medicine.

Variant of Uncertain Significance

Also known as a VUS, a Variant of Uncertain Significance is a type of genetic test result. These results are considered by experts as “inconclusive” test results because they are neither positive nor negative for a known mutation. This means that, at the time of testing, the laboratory cannot determine whether the gene change is a harmful change which increases the risk for cancer, or a benign variant which does not increase cancer risk. 

VUS

Variant of Uncertain Significance. A VUS is a type of genetic test result. These results are considered by experts as “inconclusive” test results because they are neither positive nor negative for a known mutation. This means that, at the time of testing, the laboratory cannot determine whether the gene change is a harmful change which increases the risk for cancer, or a benign variant which does not increase cancer risk. 

Zejula

Zejula is a type of cancer treatment known as a PARP inhibitor. Zejula is FDA approved for maintenance therapy in any woman with certain types of recurrent ovarian, fallopian tube or primary peritoneal cancer. 

Also see Niraparib.