In alphabetical order
Adenoma: An ordinarily benign neoplasm of epithelial tissue. If an adenoma becomes cancerous, it is known as an adenocarcinoma.
Apc: The abbreviated name of the adenomatous polyposis coli gene (Apc), located on chromosome 5q. The majority of colorectal cancer polyps have mutations in both copies of the Apc gene. Patients with FAP inherit a single mutant copy of this gene.
Apoptosis: Programmed cell death.
Assay: A test for a particular substance, or to subject to analysis.
BAT-26: A marker of microsatellite instability, BAT-26 is a deletion in intron 5 of MSH2, one of the main genes associated with Hereditary Non-Polyposis Colorectal Cancer syndrome.
Benign: Not cancerous. Unlike malignant tumors, benign tumors do not invade adjacent tissues and do not spread throughout the body. As such, benign tumors generally are not life threatening. However, cells in some benign tumors can acquire additional changes so that they become malignant or cancerous.
Biopsy: The process of removing tissue from living patients for diagnostic evaluation.
Bowel Preparation: Purging and cleansing of the bowel of fecal and other matter to assure clear evaluation of the bowel.
Bowel wall: Lining of the bowel.
Cancer: A common term for disease characterized by the uncontrolled, abnormal growth of cells which have begun to spread to tissues from which they did not originate. Cancer cells can spread locally or through the bloodstream and lymphatic system to other parts of the body.
Carrier: An individual who possesses one copy of a mutant allele that causes disease only when two copies are present.
Chromosome: A threadlike strand of DNA that carries genes and transmits hereditary information. Each chromosome can contain hundreds or thousands of individual genes. The number of chromosomes in the normal human cell is 46 (23 pairs).
Chromosome arms: Chromosomes have two arms, the p arm (short) and the q arm (long) which are separated from each other by the centromere, the region of a chromosome to which spindle fibers attach during cell division
Colon: Another name for the large intestine. The section of the large intestine extending from the cecum to the rectum. An adult colon is approximately five to six feet in length and is responsible for absorbing water and forming, storing and expelling waste.
Colonoscopy: An endoscopic procedure to examine the entire rectum and colon. A colonoscope is a long, flexible, lighted tube with a tiny lens on the end used to visualize the whole colon and look for the presence of growths.
Colorectal cancer: Cancer that occurs in the rectum or the colon. Colorectal cancer is the most deadly cancer among non-smokers, yet it is one of the most preventable types of cancer. Colorectal cancer occurs equally in men and women and early detection of the disease can significantly reduce mortality.
Deletion Technology: Deletion technology detects short deletions and insertions in the BAT-26 mononucleotide marker. This methodology can be used to detect cancers associated with deficiencies in the normal DNA mismatch repair mechanism.
Diagnostic: Aiding in the determination of the existence or nature of a disease.
DNA Integrity Assay (DIA): The analysis of DNA fragment lengths contained within a patient's DNA sample. DIA detects longer human DNA fragments that are associated with genetic abnormalities which may lead to cancer. This proprietary technology of EXACT Sciences adds sensitivity to the multiple mutation panel, without requiring specific knowledge about which genes cause the cancer.
DNA (deoxyribonucleic acid): A nucleic acid that carries genetic information on cell growth, division, and function. DNA consists of two long strands of nucleotides twisted into a double helix and held together by hydrogen bonds. The sequence of nucleotides determines hereditary characteristics.
Epidemiology: The study of the incidence, distribution and determinants of an infection, disease or other health-related event in a population. Epidemiology can be thought of in terms of who, where, when, what, and why. That is, who has the infection/disease, where are they located geographically and in relation to each other, when is the infection/disease occurring, what is the cause, and why did it occur.
Epithelium/Epithelia: Membranous tissue constructed of one or more layers of cells that cover the internal and external surfaces of the body and its organs.
Familial colon cancer: Colon cancer that is more likely to develop within families.
Familial High Risk: There are several criteria one must meet to be categorized as familial high risk. 1) at least 3 family members with any of the following cancers: colorectal, endometrical, ureter, kidney (transitional cell only) and small bowel. One is a first degree relative. 2) two consecutive generations have one of these cancers. 3) at least one individual younger than 50 years of age. 4) people with Familial Adenomatous Polyposis (FAP) are not included.
Familial Adenomatous Polyposis (FAP): An inherited disorder of the gastrointestinal tract in which there are hundreds to thousands of precancerous polyps, usually caused by an inherited mutated copy of the Apc gene.
False Positive: A test result that is read as positive when the disease is not present.
Fecal occult blood test (FOBT): A test to check for hidden blood in the stool. The presence of blood in stool may be a sign of cancer.
Flexible sigmoidoscopy: The process by which the rectum and lower third of the colon (sigmoid colon) are inspected. A sigmoidoscope is a long, flexible, slender tube with a lens on the end used to visualize a portion of the colon to look for the presence of growths.
Founder effect (founder mutation): when a particular gene mutation is present in a population at increased frequency because it was present in a small isolated group of “founders," ancestors who gave rise to most of the individuals in the present day population.
Gastroenterology: The study of diseases of the digestive tract and organs associated with digestion, such as the liver and pancreas.
Gastrointestinal tract: The digestive system, consisting of the esophagus, stomach, small intestine and large intestine.
Gene: A segment of a DNA molecule located on a chromosome containing information about hereditary characteristics, such as susceptibility to certain diseases. Genes are the basic units of heredity, each occupying a particular place on a chromosome.
Genetic Counselling: providing an assessment of heritable risk factors and information to patients and their relatives concerning the consequences of a disorder, the chance of developing or transmitting it, how to cope with it, and ways in which it can be prevented, treated, and managed.
Genetic mutation: A change in genetic material, usually in a single gene.
Genetic predisposition: Any condition in which genetic make-up renders the individual more susceptible to disease.
Genome: A complete set of chromosomes representing all of the genetic information of the organism.
Genomics: The study of the genome and its significance to pathology and disease.
Hereditary: Genetically transmitted from parent to child.
Hereditary Non-Polyposis Colorectal Cancer (HNPCC): An inherited disorder in which there is an increased tendency to develop colorectal cancer without a significant number of polyp precursors. HNPCC is specifically associated with inherited mutations in five genes.
Heterozygosity: Having different allelic genes at one or more loci in homologous chromosomes (i.e. having the same genetic location). If the same allele occupies both loci in a pair of chromosomes, the individual is said to be homologous for the allele. If not, the individual is said to be heterozygous for the allele.
K-ras: Oncogene demonstrated to play a significant role in colorectal cancer.
Lesion: A part of a tissue that has been structurally changed due to disease. Lesion is sometimes used as another word for a tumor.
Loss of Heterozygosity: e-LOH is a statistical methodology that utilizes single nucleotide polymorphisms as markers to identify the loss of a missing gene. By comparing the ratio of maternal DNA to paternal DNA, one may be able to identify chromosomal loss that may be associated with many cancers.
Luminal: The layer of a tubular organ (e.g., the colon) which forms the inner surface.
Lymph Nodes: An oval structure located along lymphatic vessels which function as a filter of foreign matter and the production of lymphocytes. When enlarged, it provides a sign of infection or malignancy.
Malignant: Cancerous. Malignant tumors, or cancer, have the ability to invade adjacent tissues and spread throughout the body. As such, malignant tumors can become life threatening.
Metastasis: The spread of cancer cells from one organ or body part to another area of the body. This movement of tumor growth occurs as cancer cells break off the original tumor and spread by way of the blood or lymph system.
Microsatellites: Repeated sequences of DNA present in everyone, of a set length.
Microsatellite Instability (MSI): Microsatellite instability is a change that occurs in the DNA of certain cancer cells in which the number of repeats of microsatellites is different than the number of repeats that was in the DNA before the cancer. Mutations in mismatch repair (MMR) genes cause MSI in some colon tumors.
Microscopic Feature: a characteristic noticeable on microscopic examination
Mismatch repair gene: The function of these genes is to correct naturally occurring “spelling” errors in DNA. They are thus classified as “caretaker” genes. A mutation in these genes, such as MLH1 and MSH2, may lead to an increased risk of colorectal cancer, but not all colorectal cancer patients will have these gene mutations.
Morbidity: A diseased state.
MLH1 and MSH2 These are two genes, when mutated may lead to an increased risk of colorectal cancer and certain other cancers, however not all colorectal cancer patients will have these gene mutations.
Mucosa: Mucous tissue lining various tubular organs.
Multiple Mutation Assay: Each element of the multiple mutation detection panel detects a base point mutation within a cancer-related gene. This methodology was designed to allow sensitive and specific detection of known single base DNA mutations that may lead to cancer.
Mutation: A relatively permanent change in a gene.
Non-invasive procedures: Procedures that do not require insertion of an instrument or device through the skin or bodily orifice for diagnosis or treatment.
Oncogene: Gene that when mutated or expressed at abnormally high levels contributes to converting a normal cell into a cancerous cell.
p-53: Gene which is activated when DNA damage occurs to correct DNA damage before a cell divides. Cells won't divide if turned on. If mutated cell will divide and produce mutant copies.
Polymorphism (polymorphic gene): A naturally occurring variation in the sequence of genetic information on a segment of DNA among individuals
Polyp: A usually nonmalignant growth or tumor protruding from the mucous lining of an organ, such as the colon. Left untreated, polyps have an increased risk of becoming cancerous.
Pre-cancerous: Condition of the tissue, such as a polyp, that can turn into a cancer if not treated or removed.
Predispositional: Any condition, genetic or other, that renders an individual more susceptible to disease.
Prognosis: The forecast of the probable outcome of an illness
Prospective Study: A research study looks forward in time, and follows events as they occur.
Psychosocial: relating social conditions to mental health
Retrospective Study: A research study that looks backwards in time at events that have already taken place
Risk: the likelihood of developing a disease. A person's risk is determined by a number of factors including personal and family health history. This information is assessed by a genetic counsellor or geneticist and can range in categories from "low risk', "intermediate or average risk" to "high risk".
Risk Communication: A process in which a genetic counsellor or other medical professional interprets genetic test results and advises patients of the consequences for them and their offspring.
Risk Factor: Activity or factor that may increase the chance of developing a disease
Screening: examination of a group of usually asymptomatic individuals to detect those with a high probability of having a given disease.
Sensitivity: Measures a test's ability to detect the presence of disease when an individual actually has the disease.
Sigmoidoscopy: see ‘Flexible sigmoidoscopy’
Specificity: Measures a test's ability to correctly identify individuals who are disease-free. A failure in specificity, commonly referred to as a "false positive," is the failure of a test to correctly identify an individual who is disease free.
Tumor: An abnormal mass of tissue that results from excessive cell division. Tumors may be benign (not cancerous) or malignant (cancerous).
Tumor suppressor gene: Gene that normally functions to inhibit cell growth and division cycles.