abdominal hysterectomy – a surgery to remove the uterus through an incision in the abdomen.

active immunotherapy – the prevention or treatment of disease by stimulating the immune system.

adenocarcinoma – a cancer that develops from the cells that line many of the body’s organs.

adjuvant therapy – a treatment given in addition to the primary treatment, to make treatment more successful.

antibody – one of various blood proteins made by the body to help protect it from infection.

axilla – the armpit.

axillary dissection – surgery in which a sample of lymph nodes are removed from the armpit to determine if the cancer has spread.

axillary lymph node – a lymph node located in the armpit, which filters or drains unwanted substances, such as bacteria, viruses and cancer cells, from the breast.

barium enema – a procedure used to take x-rays of the colon and rectum, to diagnose diseases and conditions that affect the lower gastrointestinal tract. The colon is partly filled with a liquid containing barium, and x-rays are taken. For a double-contrast barium enema (or barium enema with air contrast), the barium is drained and the colon is then filled with air, to provide a more detailed view of the colon.

Barrett's esophagus – a disorder in which the lining of the esophagus undergoes cellular changes due to chronic irritation and inflammation. A person with Barrett's esophagus is at increased risk of developing cancer of the esophagus.

basal cell carcinoma – a type of skin cancer that begins in the lowest layer of the epidermis, the basal cell layer. Basal cell carcinoma usually begins on areas most exposed to the sun, such as the face, neck, forearms and back of the hands.

benign growth – a non-cancerous lump.

bilateral salpingo-oophorectomy – a surgery to remove both ovaries and both fallopian tubes.

bilateral oophorectomy – a surgery to remove both ovaries.

bilateral salpingectomy – a surgery to remove both fallopian tubes.

biopsy – the removal of a sample of tissue, using a needle or surgery, for laboratory examination.

bone marrow biopsy – a test in which a needle is inserted into bone to remove a sample of marrow, which will be checked for cancer cells.

brachytherapy – the insertion of a pellet of radioactive material into or near the cancer, to shrink or kill cancer cells. Also known as local or internal radiation.

breast self-examination (BSE) – an exam performed by a woman to feel for any lumps or changes in her breasts.

breast-conserving surgery – a surgery to remove a cancerous tumour from the breast without removing the breast.

Breslow measurement – a technique used by a pathologist to measure the thickness of a melanoma.

bronchoscope – a long, thin tube, inserted into the nose or mouth, used to look for disease in a person’s airway and remove growths.

bronchoscopy – a procedure that uses a long, thin lighted tube, called a bronchoscope, to view the inside of a person’s airway. Bronchoscopy can be used to diagnose cancer and perform some treatment procedures.

CA-125 blood test – a test that measures the level of a protein called CA-125 in the bloodstream. Results that show high levels of CA-125 may indicate the presence of ovarian or some other kinds of cancer. The test may also be used to assess how well a treatment is working. The test has several limitations: an elevated level of CA-125 can also be caused by other conditions, many of which are benign (such as fibroids, pregnancy, endometriosis). Also, the test cannot distinguish between a cancerous ovarian lump and a benign (non-cancerous) ovarian lump.

cancer – a disease characterized by an uncontrollable and abnormal growth of cells.

carcinoma in situ – abnormal cells found only in the area where they originated, not in the surrounding tissue. These cells can become cancerous and spread to the surrounding tissue.

cervical dysplasia – abnormal, non-cancerous cells on the cervix. If not treated, cervical cancer can develop.

cervix – the lower, narrow end of the uterus leading to the vagina.

chemoprevention – the use of drugs, vitamins, minerals or food supplements to slow or prevent invasive cancer from developing.

chemotherapy – the use of anti-cancer drugs to kill cancer cells. Chemotherapy is given by injection or in the form of pills.

clinical breast exam – an exam performed by a health-care professional to feel for any changes in the breast.

clinical trials – studies to test the benefits and safety of possible new treatments in groups of volunteers.

colonic surgery – an operation to remove the cancer and a length of normal tissue on either side of the cancer as well as the nearby lymph nodes. The remaining two ends of the colon are then reattached. Also known as a segmental colonic resection or bowel resection.

colonoscopy – a test used to examine the inside of the colon for cancer and polyps, and possibly remove tissue to check for signs of disease. The procedure uses an instrument called a colonoscope, a long, flexible tube with a small camera on one end, placed through the rectum into the colon.

colostomy – a surgical procedure in which the end of the colon is sewn to an opening in the abdomen, through which waste leaves the body. The patient then wears a bag to collect expelled waste. A colostomy may be temporary or permanent.

colposcopy – an in-office examination in which the cervix is viewed through an instrument called a colposcope.

computed tomography (CT scan) – a non-invasive imaging technique that uses a computer to assimilate numerous x-ray images into a two dimensional cross-sectional image. Also known as a computed axial tomography (CAT) scan.

cone biopsy – a surgery to remove a cone-shaped piece of tissue from the cervix for examination. This procedure is usually used for diagnosis, rarely for treatment.

connective tissue – tissue that makes up various parts of the body, including cartilage, bone and collagen, which surrounds and supports other tissues and organs.

cyst – a fluid-filled sac, usually benign.

cystoscopy – a test used to determine if cancer has spread to the bladder. The doctor examines the inside of the bladder using an instrument called a cystoscope, a thin lighted tube with a lense on one end.

cytokines – proteins that help regulate the immune system.

dermis – the middle layer of the skin. The dermis is much thicker than the epidermis. It contains hair shafts, sweat glands, blood vessels and nerves.

dilation and curettage (D & C) – a procedure in which the cervix is dilated and a special surgical instrument, called a curette, is used to scrape tissue from inside the uterus.

DNA (deoxyribonucleic acid) – the molecule that encodes genetic information in cells, determining their functions.

duct – a tube that transfers excretions or secretions in the body.

ductal carcinoma in situ (DCIS) – cancer that is found only in the ducts of the breast and has not spread to the surrounding tissue.

ductogram – a test that helps to determine the cause of a nipple discharge. Discharge is collected and examined under a microscope to see if any cancer cells are present.

dysplastic cells – abnormal cells which could eventually become cancerous.

dysplastic mole – an atypical mole, meaning that its appearance is different from common moles due to its colour, border and/or size.

electrofulgeration – a procedure that destroys a cancer by burning it with an electric current.

endometrial biopsy – a procedure to remove a sample of tissue from the lining of the uterus, so it can be examined under a microscope. The endometrial tissue is obtained through a thin suction tube inserted into the uterus, through the cervix.

endometrial carcinoma – a cancer in the cells lining the uterus.

endometrial hyperplasia – an increased growth of the endometrium. Unlike a cancer, mild or simple hyperplasia can go away on its own or with hormone treatment. If untreated, simple atypical hyperplasia and complex atypical hyperplasia have a risk of becoming cancerous (in about eight and 29 percent of cases, respectively).

endometrium – the lining of the uterus.

enterostomal therapist – a health-care professional trained to help people with their colostomies.

epidermis – the top layer of the skin. It is a thin layer of skin, which protects the deeper layers of skin and the organs.

epithelium – a layer of tissue covering glands, organs and other structures in the body.

estrogen – the female sex hormone which develops the female secondary sex characteristics and has a variety of functions during the menstrual cycle.

estrogen therapy – the use of estrogen, usually after menopause, to lessen the effects of having a low level of this hormone.

extensive stage – occurs when cancer in one lung has spread to the other lung, to lymph nodes on the other side of the chest or to distant organs.

external beam radiation – radiation therapy focused from outside the body onto the cancer, to shrink or kill cancer cells.

fecal occult blood test – a stool sample test used to look for the presence of blood in the colon, rectum or other parts of the gastrointestinal tract.

fibrocystic changes – benign (non-cancerous) changes in the breast.

fine needle aspiration – a method of removing fluid or cells from the the breast, lymph nodes, thyroid or other parts of the body, to check for signs of cancer or other conditions.

fine needle aspiration biopsy – a biopsy that uses a syringe with a thin needle to remove small tissue fragments from a tumour.

five-year survival rate – the percentage of patients who live at least five years after their cancer is diagnosed. Can be used to help a patient and health-care provider understand a prognosis and develop a treatment plan. A five-year survival rate cannot provide information about a particular individual. Also, people represented in such a statistic were diagnosed more than five years earlier, so advances in diagnosing and treating the cancer are not reflected in the statistic. This means that the chance of survival of a person diagnosed today is often higher than the chance indicated by the five-year survival rate.

gastrointestinal stromal tumours – tumours of the connective tissue in the wall of the colon and rectum.

gene therapy – an experimental therapy that treats a disease by introducing genetic material to a person’s cells.

genes – formed from DNA and responsible for the inherited characteristics that make beings different from one another. Humans have approximately 35,000 genes.

genetic mutation – a permanent genetic change. A genetic mutation can be inherited, caused by forces within a person’s body (such as hormones and viruses), or caused by forces outside of a person’s body (such as environmental carcinogens). Some genetic mutations predispose people to certain kinds of cancer.

genetic testing – a method by which a woman learns if she is carrying a mutated gene.

glands – organs in the body which secrete a substance, such as hormones, sweat, tears, saliva and digestive juices.

grading – a system for analyzing a tumour to determine the extent or risk of spread or recurrence, and appropriate treatment choices. Also known as staging.

gynecologic oncologist – a doctor who specializes in cancers of the female reproductive system.

hormone – a substance secreted by certain cells, that has a regulatory effect on the activity of organs. Hormones affect many bodily processes, such as growth and development, metabolism, sex drive, reproduction and mood.

hormone receptors – structures on cells to which hormones attach themselves, affecting the activity of that cell. If cancer cells have hormone receptors, they usually respond to hormone therapy.

hormone therapy (formerly known as hormone replacement therapy or HRT) – the use of estrogen and/or progesterone, usually taken by postmenopausal women to relieve moderate to severe symptoms of menopause. Hormone therapy may also be taken to slow or stop the growth of certain cancers.

Horner's syndrome – a group of symptoms caused by nerve damage in the face and eye. These symptoms include drooping or weakness of one eyelid, reduced or absent perspiration of one side of the face, and a smaller pupil in one eye.

human papillomavirus (HPV) – one of a group of viruses. Most strains of HPV are harmless and most people with HPV experience no symptoms whatsoever; however, certain strains of HPV can cause cervical and anal cancer; and certain low-risk strains can cause wart-like growths on the genitalia. HPV is the world’s most common sexually transmitted infection.

hyperplasia – excess cell growth; an abnormal increase in the amount of normal cells in an organ or tissue.

hypertrophic osteoarthropathy – a disease of the joints and bones, characterized by clubbing of the fingers and toes, and swelling and pain in the joints. Primary hypertrophic osteoarthropathy is inherited. Secondary hypertrophic osteoarthropathy is usually associated with a chronic condition, sometimes cancer.

hysterectomy – the surgical removal of the uterus.

hysteroscopy – a test in which a gynecologist examines the inside of the uterus through a thin lighted tube.

imaging tests – tests that involve taking pictures of the inside of the body, using x-ray or other technology.

immune system – the group of organs and cells that defends the body against infections and diseases.

immunotherapy – treatment that stimulates the immune system to fight infections and diseases, such as cancer.

incisional and excisional biopsies – cuts through the full thickness of skin to remove a wedge or ellipse of skin for examination.

infiltrating ductal carcinoma – cancer that begins in a duct in the breast and spreads to the surrounding fatty tissue.

infiltrating lobular carcinoma – cancer that begins in the lobules of the breast and can spread to other parts of the body.

interferon – proteins released by the cells, which help to fight viral infections and diseases, such as cancer. Interferons are produced naturally by the body and can also be produced in a lab.

intravenous pyelogram – a test that examines the path of a dye after it is injected into a vein.

invasive cancer – cancer that has spread beyond the area where it started.

laparoscopic lymph node sampling – a procedure in which a tube is inserted into the abdomen, through a small incision, and lymph nodes near a tumour are removed to see if they contain cancer.

laser surgery – surgery that uses a laser beam to burn off cells or tumours, or to remove a small piece of tissue for study.

LATS flap – a surgical procedure that moves the broad fan-shaped back muscle to the site of the mastectomy and uses the overlying skin to create a new breast. A saline implant is usually added.

leiomyosarcoma – a cancer that begins in muscle, most often of the uterus.

limited stage – the cancer is only in one lung, the tissue between the lungs and the lymph nodes on the same side of the chest.

lipomas – soft growths of benign (non-cancerous) fat cells.

lobectomy – the removal of part of a lung.

lobular carcinoma in situ – cancer that is found only in the lobes of the breast and has not spread to the surrounding tissue.

lobule – a subdivision of a lobe of an organ.

local excision – the removal of superficial cancers and a small amount of nearby tissue.

local radiation – the insertion of a pellet of radioactive material into or near the cancer, to shrink or kill cancer cells.

local therapy – a type of therapy used to treat the main or primary tumour and the area around it.

lumpectomy – surgery in which the breast lump and some of the surrounding tissue is removed. Also called a partial mastectomy.

lymph node dissection – the surgical removal of lymph nodes to see if they contain cancer.

lymph nodes – glands that are part of the body’s defense system. They drain impurities from the body.

lymphatic tissue – all of the tissue that is part of the lymphatic system.

lymphedema – a condition that occurs when the lymph node system is not draining enough fluid, resulting in fluid retention and swelling of the arm or leg.

lymphoma – any cancer of the lymphatic system. There are two main types of lymphoma: Hodgkin lymphoma and non-Hodgkin lymphoma.

magnetic resonance imaging (MRI) – a non-invasive imaging technique that uses powerful magnets and radio waves to see inside the body. Unlike CAT scans and x-rays, MRI does not use radiation and produces more detailed images.

malignant growth – a cancerous growth that has the potential to spread.

malignant mixed mesodermal tumour (MMMT, or carcinosarcoma) – a cancer that affects both the tissue that lines the internal organs and the connective tissue, such as bone, cartilage and fat.

mammogram – a low-dose x-ray of the breast, used to check for changes or abnormalities.

mastectomy – the surgical removal of the breast.

mediastinal lymph nodes – lymph nodes located in the centre of the chest between the two lungs.

mediastinoscopy – a procedure in which a thin tube-like instrument, called a mediastinoscope, is inserted through an incision in the chest to examine the area between the lungs. Tissue samples can be taken from the lymph nodes in this area (the mediastinal lymph nodes) through this tube.

medical oncologist – a physician specializing in the diagnosis and treatment of cancer.

melanin – pigments in the cells that produce the skin's colouring.

melanocytes – the cells that produce the skin's colouring (melanin).

melanoma – a skin cancer that begins in the melanocytes, the cells that produce the skin's colouring (melanin).

menopause – the ending of menstruation, usually occurring around the age of 50.

metastatic – cancer that has spread, through blood vessels or lymphatic channels, to other parts of the body.

micrometastases – deposits of cancer that are too small to be detected by imaging tests.

microsurgery – surgery performed under a microscope on parts of the body that are very small.

modified radical mastectomy – the removal of all breast tissue including the nipple, as well as some or all of the lymph nodes under the arm. Some of the muscles from the chest wall may also be removed.

myometrium – the layer of smooth muscle of the uterus.

needle biopsy – the removal of a sample of tissue or fluid using a needle. The sample is then examined under a microscope to see if cancer cells are present. If a wide needle is used, the procedure is called a core biopsy; if a fine needle is used, it is called a fine-needle aspiration biopsy.

neoadjuvant therapy – systemic or radiation therapy administered prior to the primary treatment.

non-invasive cancer – cancer that has not spread to surrounding tissue.

nonmelanoma – the most common skin cancer. Nonmelanoma cancers originate in the basal or squamous cells. They are called nonmelanoma because they develop from skin cells other than melanocytes.

non-small cell lung cancer – the most common types of lung cancer. The name describes the way these cancer cells look under a microscope.

open biopsy – a procedure in which the skin is cut and a lump or mass is removed along with the surrounding tissue. The tissue is then examined under a microscope.

outpatient basis – medical care provided to a patient who does not stay at the hospital overnight.

Pancoast tumour – a rare cancer of the upper part of the lungs. A Pancoast tumour can damage a nerve that passes from the upper chest into the neck.

Pap test (Pap smear) – a test, typically done in a doctor’s office, to check for the presence of infection and cancerous or pre-cancerous cells on the cervix. The doctor uses a speculum to see inside the vaginal canal, and scrapes some cells from the cervix, which are later examined under a microscope. Women should have pap tests regularly, as part of their routine physical exams.

paraneoplastic syndrome – the symptoms that occur when the cells of some cancers produce hormones or other substances that enter the bloodstream. These substances can cause problems with distant tissues and organs, even when the cancer has not spread to those tissues and organs.

partial mastectomy – surgery in which a cancerous breast lump and some of the surrounding tissue is removed. Lymph nodes under the arm may be removed as well. Also called a lumpectomy.

pathologist – a physician who specializes in diagnosing disease by studying tissue and cell changes.

pelvic exenteration – the surgical removal of the rectum as well as nearby organs in the pelvis, such as the bladder, uterus, cervix, vagina and nearby lymph nodes. Usually performed to remove cancer.

pelvic lymph node dissection – the surgical removal of some of the lymph nodes of the pelvis.

photodynamic therapy – treatment to kill cancer cells, using drugs that become active when exposed to light and a specific kind of light that is shone directly on the cancer.

pleura – the lining that surrounds and protects the lungs and the inside of the chest cavity.

polyp – a mushroom-like growth that protrudes from a mucous membrane. Polyps are usually benign, but cancer cells can develop inside some types of polyp.

polypectomy – a surgery to remove a polyp.

premature menopause – the ending of menstruation prior to the age of 40.

proctoscopy – a test used to examine the rectum to look for signs of disease, such as cancer. The doctor examines the inside of the rectum using a lighted tube called a proctoscope.

progesterone – a female sex hormone that prepares the uterus for pregnancy and the breasts for milk production.

progestin – any hormone that helps to prepare the uterus for egg implantation and pregnancy, such as natural progesterone or synethetic substances.

prosthesis – an artificial substitute for a missing part of the body.

punch biopsy – a procedure to remove a deep sample of skin by cutting through all the layers of the skin, including the dermis, epidermis and upper parts of the subcutis.

radiation oncologist – a physician specializing in the use of radiation to treat cancer.

radiation therapy – uses high-energy radiation to kill or shrink cancer cells. External beam radiation focuses radiation from outside the body onto the cancer. Local radiation involves placing a small pellet of radioactive material directly into or near the cancer. Systemic radiation therapy is given in liquid form (orally or by injection) and travels throughout the body.

radical hysterectomy – the removal of the uterus, the tissues next to the uterus (parametrium and uterosacral ligaments), the cervix and the upper part of the vagina next to the cervix. Sometimes the ovaries, fallopian tubes and nearby lymph nodes are removed as well.

radical mastectomy – removal of the entire breast, lymph nodes and muscles of the chest wall.

radiology department – the area of a hospital responsible for providing diagnostic imaging and treatments.

reconstructive surgery – an operation to reconstruct or restore the appearance of a part of the body that was previously removed or operated on.

rectal exam – a test used to examine the lower rectum. A doctor or health-care provider inserts a gloved finger into the rectum to feel for abnormalities. Also called a digital rectal exam or DRE.

recurrence – a relapse of cancer after successful treatment.

re-excision – a procedure to re-open and remove more tissue from a site where an initial excision was performed, to make sure that no cancer cells remain.

relative survival rates – a way of comparing the survival rate of patients with a given type and stage of cancer with the survival rate of people who do not have the cancer. Percentages are derived from figures that do not include patients who died of other diseases.

saline implant – a sac filled with sterile saltwater inserted under the skin of the chest wall, to restore or improve the shape of the breast.

sarcoma – a cancer in the supportive tissues, which includes bone, fat and muscle.

screening – the use of tests to detect a disease in people who do not have symptoms of that disease. Screening tests, such as routine Pap tests and mammograms, are performed to find disease at an early stage and improve the chance of curing it effectively.

sentinel lymph node biopsy – a procedure used to remove a lymph node and check for the spread of cancer (e.g. breast cancer or melanoma). The procedure involves injecting a radioactive dye into the region of the tumour. The dye is carried by the lymph system to the lymph node closest to the tumour. This node is called the sentinel node. Once the sentinel node is identified, a biopsy is taken. If the cancer has spread, this node is the most likely to contain cancer cells. If the sentinel node contains cancer, more lymph nodes are removed. If no cancer is found, further lymph node surgery may not be required.

sigmoidoscopy – a test that allows a doctor to look at the inside of the rectum and lower part of the colon for cancer, polyps and other abnormalities. The doctor uses an instrument called a sigmoidoscope, a thin, lighted tube with a lense on one end, which is inserted in the rectum. During the procedure, small growths may be removed or a biopsy may be taken.

simple (or total) mastectomy – surgery to remove the entire breast, but not the lymph nodes from under the arm or the muscle tissue from below the breast.

simple excision – a surgery in which the tumour is cut out, along with a small amount of normal (non-cancerous) tissue at the edges.

simple hysterectomy – the removal of the uterus (the body of the uterus and the cervix). The loose connective tissue around the uterus, called the parametrium, and the tissue connecting the uterus and sacrum, called the uterosacral ligaments, are not removed. Hysterectomies can be done in two ways: through an incision in the abdomen (an abdominal hysterectomy) or through the vagina (a vaginal hysterectomy).

small cell lung cancer (oat cell lung cancer) – an aggressive form of lung cancer. The cancer cells are small and can spread quickly. This type of cancer is usually related to smoking.

SPF (sun protection factor) – a scale used for rating sunscreen strength. The higher the SPF, the more protective the sunscreen. A sunscreen with an SPF of at least 15 provides the best protection from the harmful rays of the sun.

sputum – mucous or phlegm mixed with spit, coughed up from the lungs.

sputum cytology – the microscopic examination of cells in coughed up phlegm, to look for abnormalities.

squamous cell carcinoma – a form of skin cancer that begins in the upper layer of the epidermis and accounts for about 20 percent of all skin cancers. Squamous cell carcinoma typically appears on the areas of the body that are most exposed to the sun, such as the face, ears, neck, lips and backs of the hands, or within scars or skin ulcers elsewhere on the body. Less often, they form in the skin of the genital area.

squamous cells – cells found on the surface of the cervix and the skin.

staging – a system for assessing whether a tumour has spread and how far it has spread. The stage of the cancer helps determine how to treat the cancer.

stroma – supporting connective tissue.

subcutis – the deepest layer of the skin. The subcutis keeps in heat and has a shock-absorbing effect that helps protect the body's organs from injury.

surgical oncologist – a physician specializing in the use of surgery to treat cancer.

syndrome – a condition characterized by a group of symptoms.

systemic disease – a disease affecting the whole body.

systemic therapy – treatment, in the form of injections or pills, that travels through the bloodstream, in order to reach cancer cells that may have spread.

tamoxifen – a drug used to treat breast cancer, to prevent cancer in women who are at high risk for developing the disease, and to prevent recurrence. This synthetic hormone is sometimes prescribed to treat other cancers as well.

tissue expander – an empty sack implanted into the body to provide a pocket for a saline implant. Sterile saline is injected into the expander over a period of three to six months, after which the expander is removed and replaced with a saline implant.

tumour – an abnormal mass of tissue resulting from excessive cell division. A tumour can be malignant (cancerous) or benign (non-cancerous).

ultrahysterosonogram – a test that allows a doctor to check for any abnormalities in the lining of the uterus. Saline (salt water) is introduced into the uterus through a catheter before a transvaginal sonogram is done.

ultrasound – a diagnostic technique using sound waves to view different parts of the body, especially internal organs.

ultrasound-guided needle biopsy – a procedure where tissue is removed through a hollow needle. Ultrasound imaging is used to guide the needle to the site.

unilateral oophorectomy – the removal of one ovary.

unilateral salpingectomy – the removal of one fallopian tube.

ureters – the tubes that carry urine from the kidneys to the bladder.

UVA – ultraviolet radiation from the sun that can burn the skin and cause skin cancer. UVA rays pass further into the skin than UVB rays.

UVB – ultraviolet radiation from the sun that can cause sunburns and skin cancer. UVB rays are more likely to burn the skin than UVA rays.

vaccine therapy – a vaccine that can be injected into a patient’s skin to stimulate the immune system to selectively destroy a tumour or infectious micro-organism. When used to treat cancer, cancer cells are introduced into the body to encourage the body to recognize and destroy cancer cells.

vaginal hysterectomy – the removal of the uterus through the vagina.

vaginal stenosis – narrowing of the vagina due to scar tissue.

wart – a rough-surfaced growth on the skin, caused by a virus.

white blood cells – cells that circulate in the blood and various tissues and organs. They are part of the immune system, which fights infection in the body.