Adenomatous Polyp
A mushroom-shaped growth that is found in the stomach, intestines, and colon. This type of polyp often develops into colon cancer. Removing the polyps can help prevent the development of cancer.
Adenomatous Polyposis Coli (APC) (ad-in-O-mut-us pah-li-PO-sis)
The APC gene normally makes a protein that prevents cells in the colon from becoming cancerous. If it is inherited in an altered form (mutated), it usually causes a hereditary cancer syndrome called familial adenomatous polyposis (FAP) or attenuated familial adenomatous polyposis (AFAP). People with FAP and AFAP have an extremely high likelihood of developing colon cancer.
Adenomatous Polyposis Syndromes (APS)
A term that collectively refers to the hereditary cancer syndromes that involve adenomatous colon polyps: familial adenomatous polyposis (FAP), attenuated FAP, and MYH-associated polyposis (MAP).
Amsterdam Criteria
A set of guidelines for identifying families that are likely to have a hereditary form of colon cancer called hereditary nonpolyposis colon cancer (HNPCC). These guidelines were put together in Amsterdam by inherited colon cancer experts.
Ashkenazi Jewish
The Eastern European Jewish population primarily from Germany, Poland, Lithuania, Ukraine and Russia, as opposed to the Sephardic Jewish population primarily from Spain, parts of France, Italy, and North Africa. The majority of Jewish individuals in the United States are of Ashkenazi descent.
Attenuated FAP (AFAP)
A type of inherited colorectal cancer in which individuals usually have fewer colon polyps at a later age of onset than in classic familial adenomatous polyposis (FAP). The American Gastroenterological Association (AGA) recommends genetic testing once a person has developed 20 or more cumulative adenomatous polyps, however AFAP has been diagnosed in patients with fewer polyps.
Autosomal Dominant
A pattern of inheritance. In autosomal dominant inheritance, you only need to inherit one copy of a mutated gene (from either parent) in order to be affected with the condition. It does not matter which parent you inherit the gene from, for example a father can pass on a BRCA1 gene mutation to his children.
Autosomal Recessive
A pattern of inheritance. In autosomal recessive inheritance, you must inherit two copies of a mutated gene (one from each parent) in order to be affected with the condition. Parents are most often "carriers" of a single mutated gene and therefore, do not express the disease.
Benign
A benign growth or benign tumor is not malignant (cancerous) and can not spread to other parts of the body. Benign growths are almost always less dangerous than malignant ones.
BRCA1 (BReast CAncer 1) Gene and BRCA2 (BReast CAncer 2) Gene
The BRCA1 and BRCA2 genes normally help to control cell growth. Mutations in either gene significantly increase a person's risk of developing breast and ovarian cancer. In addition to having a higher risk of developing breast and ovarian cancer, women with mutations in either BRCA1 or BRCA2 tend to develop the disease at a much earlier age than women in the general population.
Chemoprevention
The use of drugs, vitamins, or other agents to try to reduce the risk of, or delay the development or recurrence of, cancer.
Chromosomes (KRO-mo-some)
The part of the cell that contains genetic information. People have 23 pairs of chromosomes, 46 in all: 44 autosomes and two sex chromosomes. Each parent contributes one chromosome to each pair, so children get half of their chromosomes from their mothers and half from their fathers.
Colectomy
The surgical removal of the colon. A total colectomy is the surgical removal of the colon and rectum. A subtotal colectomy is the surgical removal of the colon or portions of the colon only (not the rectum).
Colonoscopy
A medical procedure that is used to screen the inside of a person's colon and rectum for abnormalities or possible cancer. In this procedure, the doctor inserts a lighted tube attached to a video camera into the colon through the anus. The advantage of this procedure over sigmoidoscopy (another surveillance technique) is that it allows the doctor to see the entire length of the colon.
Congenital Hypertrophy of the Retinal Pigmented Epithelium (CHRPE)
Freckling on the back part of the eye (the retina) that is present from birth. This harmless condition is often found in people who have familial adenomatous polyposis (FAP). CHRPE is visible only during a detailed eye examination.
De novo Mutation
An alteration in a gene that is present for the first time in one family member as a result of a mutation in a germ cell (egg or sperm) of one of the parents or in the fertilized egg itself. De novo mutations seen in FAP/AFAP have a 1 in 2 chance of being passed onto the carrier’s offspring. Approximately 20%-30% of FAP mutations are considered de novo.
Deoxyribonucleic Acid (DNA)
The molecule which encodes the genes responsible for the structure and function of an organism and allows for transmission of genetic information from one generation to the next.
Desmoid Tumor
A benign (non-cancerous) tumor that often occurs in the abdomen. This type of tumor begins in the tissue called connective tissue that connects muscle fibers to each other and to the surrounding structures. Although these tumors rarely spread to distant parts of the body, they can grow and invade nearby organs. Desmoid tumors are much more common in people who have familial adenomatous polyposis (FAP).
Disease-Causing Mutation
A change or alteration that occurs in the DNA. These mutations cause or predispose an individual to a specific disease.
DNA Sequencing
Determining the exact order of the base pairs in a segment of DNA.
Familial Adenomatous Polyposis (FAP) (ad-in-O-mut-us pah-li-PO-sis)
An inherited colon cancer syndrome in which hundreds to thousands of polyps form in a person’s colon. These polyps usually develop before the person turns 20 years old and almost always lead to colorectal cancer. This disease is caused by a change in the APC gene.
First Degree Relative
A relative who is a person's biological mother, father, full sibling, or child. Step parents, step children, or half siblings are not first degree relatives.
Flexible Sigmoidoscopy
An examination of the inside of the rectum and the first third or lower portion of the colon, called the sigmoid colon. A long, lighted tube attached to a video camera is used to see the inside of the colon. Approximately 40%-50% of the colon is visualized during a flexible sigmoidoscopy.
Gene
A segment of DNA that contains the instructions to make a specific protein (or part of a protein). Genes are contained on chromosomes. Chromosomes, and the genes on those chromosomes, are passed on from parent to child. Errors in the DNA that make up a gene are called mutations and can lead to diseases.
Genetic Counseling
A short-term educational counseling process for individuals and families who have a genetic disease or who are at risk for such a disease. Genetic counseling provides patients with information about their condition and helps them make informed decisions.
Genetic Discrimination
Unique treatment of an individual or members of that individual's family solely because of real or perceived differences from the ‘normal’ genome of that individual.
Genetic Predisposition
Having a greater than average risk of developing a disease because of inherited gene mutations.
Genetic Testing
A laboratory test that is used to determine whether a person has a change in their DNA.
Hereditary
Transmission from parent to child of information contained in the genes.
Hereditary Mutation
A gene change in the body's reproductive cells (egg or sperm) that becomes incorporated into the DNA of every cell in the body of offspring; hereditary mutations are passed on from parents to offspring. Also called germline mutation.
Hereditary Nonpolyposis Colon Cancer (HNPCC)
An inherited disorder in which affected individuals have a higher-than-normal chance of developing colorectal cancer and certain other types of cancer, often before the age of 50. Also called Lynch syndrome.
HNPCC-Related Cancers
Other primary cancers included in the HNPCC syndrome are cancers of the endometrium, ovary, stomach, kidney/urinary tract, brain, biliary tract, pancreas, small bowel, and sebaceous adenomas.
Informed Consent
Permission given by an individual to proceed with a specific test or procedure, with an understanding of the risks, benefits, limitations, and potential implications of the procedure itself and its results.
Inherit
Acquiring a trait from one's parents. Most traits, such as eye color or hair color, are inherited from a parent through genes.
Malignancy
A mass of quickly dividing cells that has become malignant (cancerous). A malignancy has the ability to spread into neighboring tissues or other parts of the body.
Metachronous
Multiple separate occurrences, such as multiple primary cancers developing at intervals.
Metastasis (meh-TAS-ta-sis)
The spread of cancer from one part of the body to another.
Microsatellite Instability
Each chromosome contains small regions of DNA called microsatellites. These are repeated regions of one or a few base pairs, for example CGCGCGCGCGCG. Each microsatellite has a specific number of times that it should repeat. If the number of repeats is increased or decreased, the region is considered unstable. Microsatellite instability is when a microsatellite does not have its proper number of repeats.
Mismatch Repair Mechanism (MMR)
A gene that makes a mismatch repair (MMR) protein. These proteins correct any mistakes that a cell makes while copying its own DNA. A mutation in a mismatch repair gene can result in an altered mismatch repair protein. When this occurs, any mistakes that take place while a cell is copying its own DNA become a permanent part of the DNA in all subsequent cells.
MLH1, MSH2, MSH6
Mismatch repair genes which, when mutated, are associated with hereditary nonpolyposis colorectal cancer.
Mutation
Any alteration in a gene from its natural state. The alterations may be disease-causing or just a normal variation that causes no harm.
MutY Homolog (MYH)
The MYH gene carries the instructions for cells to make an enzyme that is involved in the repair of DNA. If both copies of the MYH gene are inherited in an altered (mutated) form, they cause a hereditary cancer syndrome called MYH-associated polyposis (MAP). People with MAP have an extremely high likelihood of developing colorectal polyps and cancer.
MYH-Associated Polyposis (MAP)
An inherited colon cancer syndrome in which multiple adenomatous polyps form in a person's colon. The number of polyps ranges from 3 to 1000 and these polyps may be discovered over the course of a person’s lifetime. This disease is caused by a change in the MYH gene.
Osteoma
A benign bony outgrowth of membranous bones. They are found mostly on skull and facial bones and are usually not cancerous. Osteomas can be associated with familial adenomatous polyposis (FAP).
p16
The p16 gene normally helps to stop cell growth. Mutations in this gene significantly increase a person's risk of developing melanoma and pancreatic cancer.
Pedigree
A medical drawing that includes all of a person's close relatives, the relationship between family members, and health information. A pedigree is used by health care professionals to analyze a family for genetic diseases.
Pre-Symptomatic
The stage prior to the onset of symptoms related to a specific disease.
Prophylactic Mastectomy (PROH-fuh-LAK-tik ma-STEK-tuh-mee)
Surgery to reduce the risk of developing breast cancer by removing one or both breasts before disease develops. Also called preventive mastectomy.
Prophylactic Oophorectomy (pro-fi-LAK-tik o-o-for-EK-toe-mee):
Surgery to reduce the risk of ovarian cancer by removing the ovaries before disease develops. Also called preventive oophorectomy.
Selective Estrogen Receptor Modulator (SERM) (sel-EK-tiv ESS-tro-jen re-SEP-tor MOD-yew-lay-tor)
A drug that acts like estrogen on some tissues but blocks the effect of estrogen on other tissues. Tamoxifen and raloxifene are SERMs.
Sequencing Analysis
The process of determining the order of the bases in a region of DNA.
Serum CA-125
A blood test that measures the level of CA-125, a substance found in blood, other body fluids and some tissues. Increased levels of CA-125 may be a sign of ovarian cancer.
Sibling
A person who shares the same mother or father. A brother or sister who shares both parents is called a full sibling. A brother or sister who only shares one parent is called a half sibling.
Sporadic Cancer
Cancer occurring in people with no family history and no inherited cause.
Synchronous
Multiple primary cancers occurring at the same time.
Transvaginal (Endovaginal) Ultrasound
High-resolution images of the uterus and ovaries; may be used to screen for endometrial or ovarian cancer.
Tumor Suppressor Gene
A protective gene that normally limits the growth of tumors. When a tumor suppressor gene is mutated, it may fail to keep a cancer from growing.
