This glossary defines some of the medical and scientific terms commonly used by oncology physicians, nurses, researchers, and technicians.

Adjuvant Chemotherapy:
One or more anticancer drugs used in combination with surgery or radiation therapy as part of the treatment of cancer. Adjuvant usually means "in addition to" initial therapy.

Adjuvant Treatment:
Treatment that is added to increase the effectiveness of a primary therapy. In cancer, adjuvant treatment usually refers to chemotherapy or radiation therapy administered before or after surgery to increase the likelihood of cure.

One of two or more things, courses or propositions to be chosen. In applying this to cancer treatment this means making a choice to use some treatment other than what is traditionally offered by the medical community in the treatment of cancer itself.

Benign Tumour:
A tumour that is not cancerous. It is the opposite of a malignant or cancerous tumour.

Biological Therapy:
Treatment by stimulation of the body’s immune defence system. Most of these treatments are in the clinical research phase of development.

The surgical removal of a small piece of tissue for microscopic examination to determine if cancer cells are present. Biopsy is a very important procedure to determine the type of cells of which the tumour is made. Different cancer treatments may be used depending on the tumour cell type.

Bone Marrow Transplant (BMT):
A treatment of cancer that involves receiving high doses of chemotherapy and radiation (to kill all cancer cells in the body) and an infusion of healthy bone marrow (to help healthy new cells to grow). BMTs can be autologous which is the infusion of the patient’s own bone marrow or allogeneic which is the infusion of someone else’s bone marrow that is genetically similar.

Treatment with radioactive sources placed into or very near the tumour or affected area. It includes surface application, body cavity application (intracavitary), and placement into the tissue (interstitial). Sometimes this term is used interchangeably with "internal radiation therapy" or "radiation implant".

A procedure that involves placing a flexible tube with a camera at the end (called a fibroscope) down the nose or throat to visualize, and often take tissue specimens of the larynx, trachea, bronchus, and lungs.

CAT SCAN (Computerized Axial Tomography Scan):
A type of X-ray that yields a three-dimensional picture of the body that is about 100 times more sensitive than a standard X-ray. It can be given with or without contrast (medication given by drink or injection to enhance X-ray pictures).

CBC (Complete Blood Count):
A test to measure blood cells including:
WBC (white blood cells) – cells that fight infection.
RBC (red blood cells) – measured by the haemoglobin and haematocrit; these cells carry oxygen to your body’s tissues.
Platelets – cells that help form clots and prevent bleeding.

A general term for more than 100 diseases characterized by abnormal and uncontrolled growth of cells. The resulting mass, or tumour, can invade and destroy surrounding normal tissues. Cancer cells from the tumour can spread through the bloodstream or lymph system to start new cancers in other parts of the body.

A form of cancer that develops in tissues covering or lining organs of the body, such as the skin, the uterus, the lung, or the breast.

The use of drugs or hormones to kill cancer cells. Chemotherapy drugs can be given orally (by pills), by intravenous injections (into the vein), by subcutaneous injection (under the skin), by intramuscular injection (into the muscle), by intra-arterial injection (into the arteries), or topically (with creams and/or gels).

Clinical Trials:
In cancer research, a clinical trial is a study conducted with cancer patients, usually to evaluate a new drug or treatment. Studies are designed to find new and better ways to help cancer patients. Generally, cancer clinical research evaluates surgery, chemotherapy, and/or radiation therapy techniques. Methods of prevention, detection or diagnosis also may be the subject of clinical trials. Patients are never placed on a clinical trial without their permission.

A procedure that allows inspection and tissue sampling of the rectum and large intestine by inserting a flexible tube with an attached camera through the rectum.

Combination Chemotherapy:
Treatments using two or more chemotherapy drugs to achieve the most effective results.

An abnormal sac-like structure that contains liquid or semisolid material. A cyst may be benign (not harmful) or malignant (harmful).

Made-up of DNA and contained in every cell, they are sets of instructions that control biological development and function. You inherit genes as distinct units from your parents.

A scale of one to three indicating how much the tumour cells resemble normal cells (also referred to as differentiation). The lower the grade, the more the tumour cells resemble normal cells, which may mean a more favourable prognosis.

Hereditary Cancer:
A mutation carried in the reproductive cells that can be passed on from one generation to another. Only 5 – 10% of cancers are inherited.

Hormone Therapy:
Hormones are secreted naturally by various organs of the body to help regulate growth, metabolism, and reproduction. Hormones may be used alone to treat cancers or in combination with other chemotherapy drugs.

A concept of psychosocial and support care to meet the special needs of patient and their families during the terminal stages of illness. The care is provided both in outpatient and inpatient settings.

Study of the body’s mechanisms for resisting disease in the invasion of foreign substances.

A treatment that stimulates the body’s own defence mechanisms to combat disease, such as cancer. 

In Situ:
In place, localized and confined to one area; a very early stage of cancer.

Cancer that has spread from its place of origin to surrounding tissue.

Treatments done under specific standards set up by the scientific community. The treatments have some basis for being tested in humans, that they work against some animal cancers.

The surgical removal of the larynx or voice box, resulting in the loss of normal speech.

Cancer of the blood-forming tissues such as bone marrow, lymph nodes, and spleen. Leukaemia is characterized by the overproduction of abnormal, immature white blood cells.

Linear Accelerator:
A machine that creates high-energy radiation to treat cancers, using electricity to form a stream of fast-moving subatomic particles.

Localized Cancer:
A cancer still confined to its site of origin.

A clear fluid that contains white blood cells and antibodies, and is circulated throughout the body by the lymphatic system.

Swelling of the hand and arm in some women who have had surgery for breast cancer; caused by extra fluid that may collect in tissues when underarm lymph nodes are removed or blocked.

Lymph Node:
A gland which produces lymph which normally acts as a filter of impurities in the body. It can trap cancer cells which may then develop into a new tumour.

Cancer that develops in the lymphatic system. The most common type of lymphoma is Hodgkin's Disease. All other lymphomas are called non-Hodgkin's lymphomas.

Malignant Tumour:
A tumour that has been determined to be cancerous. It is the opposite of a benign/non-cancerous tumour.

The image produced by a low-dose X-ray of the breast.

A screening and diagnostic technique that uses low-dose X-rays to find tumours in the breast. Mammography can reveal a tumour too small to be felt even by the most experienced physician.

An area of tissue surrounding a tumour which has been surgically removed. Clear margins, those without evidence of cancer, indicate that the surgeon has removed all of the microscopically visible cancer.

A very aggressive type of skin cancer that can spread to other areas of the body if not detected and treated early.

The spread of cancer cells to other areas of the body. The term metastases refers to these new cancer sites.

MRI (Magnetic Resonance Imaging):
A type of diagnostic ray that uses magnets to obtain clear, detailed pictures of specific body sections. MRIs can create a greater contrast between some soft tissues (such as in the brain) which usually makes it a better tool than a CAT Scan in such cases.

The period of time following chemotherapy, usually 7-10 days after chemotherapy, when blood counts drop, thereby increasing susceptibility to infection or bleeding.

Any new abnormal growth. Neoplasms may be benign or malignant, but the term is generally used to describe a cancer.

Certain stretches of cellular DNA that, when activated, contribute to the malignant transformation of cells.

A doctor who specializes in cancer treatment.

The science dealing with the physical, chemical and biological properties and features of cancer, including the causes and progression of the disease.

Oncology Clinical Nurse Specialist:
A nurse with advanced skills and knowledge about cancer care who assists patients and their families with treatment: from prevention and detection of cancer through treatment, follow-up, cure, or terminal care.

Oncology Nurse Practitioner:
A registered nurse with advanced education in cancer care who provides nursing and medical services to cancer patients and their families.

Palliative Treatment:
Therapy that relieves symptoms, such as pain, but does not alter the course of the disease. Its primary purpose is to improve the quality of life.

The study of disease through examination of body tissues and organs. This always includes a microscopic examination. Any tumour suspected of being cancerous must be diagnosed by pathologic examination.

Peripheral Blood Stem Cell Transplant (PBSC):
A newer type of transplant similar to bone marrow transplant (BMT) that instead uses a patient’s own circulating peripheral cells as opposed to cells inside the bone marrow.

An inert substance, such as a sugar pill. A placebo may be used in clinical trials to compare the effects of a given treatment against no treatment.

The reduction of cancer risk with cancer fighting agents. A change in life-style, such as not smoking, can help prevent lung and many other cancers.

Radioactive Implant:
A source of high-dose radiation that is placed directly into and around a cancer to kill the cancer cells.

Radiation Oncologist:
A physician with special training in the use of X-ray energy for the treatment of cancer.

Radiation Physicist:
A person trained to ensure that the radiation machine delivers the right amount of radiation to the treatment site.

Radiation Therapist:
A person with special training who runs the equipment that delivers the radiation. Sometimes called a radiation technologist.

Treatment of cancer with high-energy radiation. Radiation therapy may be the only treatment used, or it may be given before surgery to reduce the size of a cancer, after surgery to destroy any remaining cancer cells, or in conjunction with chemotherapy.

Recurrence (Local):
Reappearance of cancer at its original site after a period of remission.

Complete or partial disappearance of the signs and symptoms of disease in response to treatment; the period during which a disease is under control.

A cancer of connective tissue, bone or cartilage.

Side Effects:
Usually described as after-effects, or secondary effects, of treatment. For example, hair loss may be a side effect of chemotherapy; nausea may be a side effect of radiation therapy or chemotherapy. Most treatment-related side effects can be managed.

A process involving special X-ray pictures that are used to plan radiation treatment so that the area to be treated is precisely located and marked for treatment.

Sporadic Cancer:
Cancer that develops from random changes in the cells of the body during one’s lifetime – these changes can be due to environment toxins such as tobacco. Most cancers (90 – 95%) are sporadic.

An evaluation of the extent of disease, such as cancer. A classification based on stage at diagnosis helps determine appropriate treatment and prognosis.

Stereotactic Biopsy:
A pinpoint biopsy, usually of the breast or brain, using specific equipment to determine the coordinates of the tumour to be biopsied.

Stereotactic Radiosurgery:
A type of treatment that allows high doses of radiation to be given to small areas of the brain. This treatment uses a special frame to keep the patient’s head very still, and may require an overnight hospital stay for monitoring.

The removal of a malignant tumour in an operation. Surgery is the oldest and most frequently used cancer treatment.

An abnormal tissue swelling or mass; may be either benign or malignant.

Ultrasound Examination:
The use of high frequency sound waves to locate a tumour deep inside the body. Also called ultra-sonography.