Leading Cancer Care

Cancer Dictionary

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Adenocarcinoma: Cancer that arises from glandular tissues. Examples include cancers of the breast, lung, thyroid, colon and pancreas.

Adjuvant Therapy: Chemotherapy used along with surgery or radiation therapy. It is usually used in cases where there is a high risk of hidden cancer cells remaining and may increase the likelihood of cure by destroying small amounts of undetected cancer.

Advanced Directives: Legal documents spelling out how you want your medical care to proceed, including living wills, do not resuscitate (DNR) orders and durable power of attorney.

Alopecia: Hair loss

Anemia: Having less than the normal number of red blood cells (hemoglobin) in the blood. This may be due to bleeding, lack of blood production by the bone marrow, chemotherapy side effects or to the brief survival of blood already manufactured. Symptoms include tiredness, shortness of breath and weakness.

Anorexia: Lack or loss of appetite.

Antibody: A protein in the blood that fights against an invading foreign agent (antigen). Each antibody works against a particular antigen.

Antiemetics: Drugs given to prevent or minimize nausea and vomiting.

Asymptomatic: Without obvious signs or symptoms of disease. Cancer may cause symptoms or warning signs but, especially in its early stages, cancer may develop and grow without producing symptoms.

Atypical: Not usual; abnormal.

Axilla: The armpit. Lymph nodes in the armpit are called the axillary nodes. Certain cancer, such as breast cancer, spread to the axillary nodes. Axillary lymph nodes are usually removed by surgery to determine if breast cancer is present and if treatment with chemotherapy is necessary.



Basal Cell Carcinoma: A form of skin cancer that grows very slowly and is curable in almost all cases with surgery or other local treatment.

Benign: An abnormal, noncancerous growth of tissue that does not spread to other parts of the body, as a cancerous tumor can do. Though generally not life-threatening, benign tumors can cause a wide range of problems and side effects.

Bilateral: Pertaining to both sides of the body.

Biopsy: Procedure where tissue is gathered for further testing. The microscopic examination of this tissue removed from the body is used to determine if cancer cells are present. Among the most common are needle aspiration biopsy, core needle biopsy, excisional biopsy, bone marrow biopsy and spinal tap.

Blood Cells: The red cells, white cells and platelets that make up the blood. They are made in the bone marrow.

Blood Cell Count: Also called a complete blood cell count (CBC). This test checks the number of red blood cells, white blood cells and platelets in a sample of blood.

Bolus (or push) chemotherapy: Administration of intravenous chemotherapy over a short period of time, usually five minutes or less. The other method is called infusion chemotherapy, which may last from 15 minutes to several hours or days.

Bone Marrow: The bones are hollow and their central cavity is occupied by marrow, a spongy tissue which plays a major role in the development of blood cells. Some forms of cancer can be diagnosed by examining bone marrow.

Bone Marrow Biopsy and Aspirate: A procedure in which a needle is inserted into a center of a bone, usually the hip, to remove a small amount of bone marrow for microscopic examination.

Bone Marrow Transplant (BMT): A supportive treatment in which a cancer patient’s bone marrow is replaced with healthy marrow. The main purpose of BMT in the treatment of most types of cancer is to enable the patient to be given very large, and potentially more effective, doses of chemotherapy or radiation, doses that cause severe damage to the bone marrow. There are three types of transplants: autologous (the patient’s own marrow is used); allogenic (the marrow comes from a sibling, parent or an unrelated donor whose marrow closely matches); and synogeneic (perfectly matched marrow that comes from an identical twin.)

Bone Scan: A picture of all the bones in the body taken about two hours after injection of a radioactive tracer. “Hot spots” indicate areas of bone abnormality that may indicate tumors. This test can help determine if cancer has spread to the bones, if therapy is working and if damaged bony areas are healing.

Brachytherapy: The use of a radioactive “seed” implanted directly into the tumor. This allows a very high but sharply localized dose of radiation to be given to a tumor while sparing surrounding tissue from significant radiation exposure.

Breast Self Exam (BSE): A simple procedure where an individual examines their own breast by feeling for masses and examining the skin and nipples for changes. It is recommended once a month between regular physician checkups.



Cachexia: Severe malnutrition; weakness and muscle wasting resulting from a chronic disease.

Cancer: A general term for more than 100 diseases characterized by the uncontrolled, abnormal growth of cells in different parts of the body that can spread to other parts of the body.

Carcinoma: A form of cancer that develops in the tissues covering or lining organs of the body such as the skin, uterus, lungs or breast. Eighty to ninety percent of all cancers are carcinomas.

Carcinoma in situ: The earliest state of cancer, in which the tumor is still confined to the local area, before it has grown to a significant size or has spread. In situ carcinomas are highly curable.

Catheter: A tube made of rubber, plastic or metal that can be introduced into a body cavity to drain fluid or deliver fluids or medications.

CEA (Carcinoembryonic Antigen): A tumor marker in the blood that may indicate the presence of cancer. It may be elevated in some cancers, especially of the breast, bowel and lung. By monitoring the amount of CEA, doctors can detect the presence of these cancers and assess the progress of treatment.

Cervix: Any ‘necklike’ structure; usually refers to the neck of the uterus where cancer may occur.

Chemotherapy: The use of chemicals (drugs or medications) to kill malignant cells. Numerous drugs have been developed for this purpose and most act to injure the DNA of the cells. When the DNA is insured, the cells cannot grow or survive. Successful chemotherapy depends on the fact that malignant cells are somewhat more sensitive to the drugs than normal cells. Because the cells of the marrow, the intestinal tract, the skin and hair follicles are most sensitive to these drugs, injury to these organs cause the common side effects of chemotherapy (mouth sores, hair loss).

Clinical Trials: The procedure in which new cancer treatments are tested. The treatment is evaluated for its effectiveness in reducing or eliminating disease. A clinical trial may be done by the National Cancer Institute, a drug company, clinic or a hospital to determine the most effective dose of a drug, to compare different combinations of treatments, or to determine the effect of the drug on a tumor.

Colon: The part of the large intestine that extends from the end of the small intestine to the rectum.

Colonoscopy: A technique used to visually examine the entire colon by means of a lighted, flexible instrument, called a fiberoptic colonscope.

Colostomy: A surgical procedure that creates an artificial opening in the abdominal wall for elimination of body wastes from the colon. It can be either temporary or permanent.

Colony Stimulating Factor (CSF): A substance that stimulates the growth of bone marrow cells.

CT Scan: A CT (computerized tomography) scan creates cross section images of the body tissues and organs. A CT scan can be used to measure the size of the tumor before, during and after treatment.

Cycle of treatment: Designates an intensive, clustered period of chemotherapy and/or radiation. The treatment may be given for several days or weeks, and represents one cycle of treatment. The treatment plan may call for two, three or more cycles of treatment.

Cyst: An abnormal sac-like structure that contains liquid or semi-solid material; may be benign or malignant.

Cytology: Study of cells under a microscope. Cells that have been sloughed off or scraped off organs, such as the uterus, lungs, bladder or stomach, are microscopically examined for signs of cancer.



Debulking: A procedure that removes a significant part or most of a tumor in cases where it is not possible to remove all of it. This may make subsequent radiation or chemotherapy easier and more effective.

Digital Rectal Exam (DRE): A procedure in which the physician inserts a finger into the rectum to examine this area (as well as the prostate gland in men) for signs of cancer.

Diuretics: Drugs that increase the elimination of water and salts in the urine.

Do Not Resuscitate Order (DNR): A medical order telling medical personal and others involved in your care that they should not act to revive you in the event that your heart activity ceases.

Dose Limiting: A side effect, complications or risk that makes it impossible or unwise to exceed a specific dose of a chemotherapeutic agent.

Drug Resistance: The development of resistance in cancer cells to a specific drug or drugs. If resistance develops, a patient in remission from chemotherapy may relapse despite continued administration of anticancer drugs.

Durable Power of Attorney: Allows a specific family member to legally make all your decisions, personal and financial, for you in case you become incapacitated.

Dysphagia: Difficulty in swallowing; a sensation of food sticking in the throat.

Dyspnea: Difficulty or pain when breathing; shortness of breath.

Dysuria: Difficult or painful urination; burning on urination.



Electrolytes: Certain chemicals, including sodium, potassium, chloride and magnesium, found in the tissues and blood. They are often measured as an aid to patient care.

Endometrium: The inner mucous membrane that forms the uterine wall.

Endoscopy: Any procedure that uses a hollow tube-like instrument to visualize and biopsy otherwise inaccessible areas of the body, such as the esophagus, stomach, colon, bladder or lung.

Eosinophil: A type of white blood cells that participates in allergic reactions and helps fight certain parasitic infections.

Erythema: Red patches on the skin. Erythema of the skin may be a sign of underlying infection or inflammation. Chemotherapy injections may also cause erythema of the skin. This usually disappears within several hours. Persistent redness of the skin at a chemotherapy site should be brought to the attention of a nurse or doctor.

Esophagitis: Soreness and inflammation of the esophagus due to infection, toxicity from radiation or chemotherapy, or some physical injury.

Estrogen: A female hormone secreted by the ovaries, which is essential for menstruation, reproduction and the development of secondary sex characteristics, such as breasts.

Estrogen-receptor (ER) assay: A test that determines whether the breast cancer in a particular patient is stimulated by estrogen.

Extravasation: Leakage into the surrounding tissues of intravenous fluids or drugs. Leakage of certain IV medications can damage the tissues.



Frozen Section: A technique in which tissue is removed by biopsy, then frozen, cut into thin slices, stained and examined under the microscope. A pathologist can rapidly examine a frozen section for an immediate diagnosis. This procedure is often done during surgery to help the physician decide the most appropriate course of action.



Granulocytes: A type of white blood cells which has a large number of granules in the cell body. Neutrophils, eosinophils and basophils are types of granulocytes.



Hematocrit: The percentage of the blood that is red blood cells. The normal level is about 37 to 42 in women and 40 to 45 in men. A low hematocrit is a sign of anemia.

Hematologist: A physician who specialized in the treatment of blood cell diseases.

Hematuria: Blood in the urine.

Hemoglobin: The portion of the RBC that carries oxygen. The normal value in women is from 12.5 to 14 grams, and in men about 13-15 grams.

Hepatomegaly: Enlargement of the liver.

Hodgkin’s Disease: A form of cancer that affects the lymph system. Hodgkin’s disease generally occurs in adults and can be successfully treated in the majority of patients.

Hospice: A program of caring for patients who are terminally ill. The focus of hospice care is not to cure the patient but to improve the quality of life for whatever time the patient has left and to make the dying process as comfortable and pain free as possible. Support is also offered to the patient’s family members.

Hysterectomy: The surgical removal of the uterus. May be combined with removal of the ovaries (oophorectomy).



Immunosuppression: A state in which the immune system does not function properly and its protective functions are inadequate. The patient is more susceptible to infections. This can occur as a result of intensive chemotherapy and radiation therapy. It can also occur because of disease states.

Immunotherapy: A treatment that stimulates the body’s own defense mechanism to combat disease, such as cancer.

Indwelling catheter: An indwelling catheter is a special tubing inserted into a large vein in the upper chest. The catheter is tunneled under the skin of the chest to keep it firmly in place. The external end of the catheter can be used to administer medications, fluids or blood products or to withdraw blood samples. Several types of catheters (Hickman, Broviac, etc) used for patients receiving chemotherapy and/or nutritional support.

Infusion: Administration of fluids and/or medications into a vein over a period of time.

Infusion Pumps: Small, preloaded mechanical devices used to continuously administer intravenous chemotherapy over a designated period of time.

Interferon: A natural body protein produced by a normal cell that is capable of killing cancer cells or stopping their unrestrained growth. Interferon was originally discovered as an antiviral agent, but has now been found to have some anti-cancer activity as well. Interferon may be artificially produced in large quantities using the technique of recombinant DNA.

In situ: A very early stage of cancer in which the tumor is localized in one area.

Intramuscular (IM): The injection of a drug into a muscle.

Intravenous (IV): The administration of drugs or fluids directly into a vein.

Invasive cancer: A stage of cancer in which cancer cells have spread to healthy tissue adjacent to the tumor.



Leukemia: Cancer of the blood-forming tissues (bone marrow, lymph nodes, spleen). Leukemia is characterized by the overproduction of abnormal, immature white blood cells.

Leukocytes: A synonym for white blood cells. (See White Blood Cells.)

Leukopenia: A decreased white blood cell count (below 5,000).

Living Will: A document outlining the care you want in the event that you become unable to communicate due to a coma or heavy sedation.

Localized: A cancer confined to the site of origin without evidence of spread.


Lumpectomy: Removal of a cancerous breast lump and the surrounding tissue without removing the entire breast. It is a less radical procedure than mastectomy and is usually followed by radiation treatment.

Lymphedema: Swelling, usually of an arm or leg, caused by obstructed lymphatic vessels. It can develop because of a tumor or as a side effect of surgery or radiation.

Lymph Node: One of the many small, bean-shaped structures of the immune system linked by lymphatic vessels throughout the body. They make and store many different immune cells that fight infection.

Lymphocytes: A type of white blood cells which fight viral infections.

Lymphoma: Cancers that develop in the lymphatic system – the network of lymph nodes and vessels that transport lymph fluid.



Malignant: Cancerous. Two qualities of malignancies are the tendency to penetrate the tissues or organ in which it originated, and to break off and spread elsewhere (‘metastasize’).

Mammogram: An x-ray procedure used in the screening and diagnosis of breast cancer which can reveal a tumor in the breast long before it can be felt.

Mastectomy: Surgical removal of the breast.

Melanoma: A type of skin cancer. While most skin cancers rarely spread to other areas of the body and are easily treated and cured, melanomas can be more aggressive if not detected early.

Metastasis: The spread of cancer from one part of the body to another by way of the lymph system or bloodstream. Cells in the new tumor are like those in the original tumor.

Monocytes: A type of white blood cells that assist in fighting infection. The monocyte, along with the neutrophil, are the two major microbe-eating and killing cells in the blood.

MRI (Magnetic Resonance Imaging: This techniques details cross sectional images of body structures. It differs from a CT Scan in that the patient is not exposed to x-rays. The signals generated in the tissues in response to the magnetic field are converted by computer into images of body structures.

Mucositis: Inflammation of the mucous membranes. Soreness, like ‘canker sores’, can develop in the mouth as a side effect of chemotherapy.

Myeloma: A cancer of the protein-producing plasma cells of the bone marrow. Multiple bone lesions are common.



Nadir: The lowest point to which while blood cell or platelet counts fall after chemotherapy. This usually occurs 1-2 weeks after the chemotherapy is given.

National Cancer Institute (NCI): A research center in Bethesda, Maryland that conducts clinical research on new cancer treatments throughout the United States.

Neoplasm: An abnormal growth or tumor.

Neuropathy: Malfunction of a nerve, often causing numbness, tingling or pain (sensory nerve) or weakness (motor nerve). It is sometimes a side effect of chemotherapy drugs.

Neutropenia: A blood condition characterized by the virtual absence of neutrophils, one type of white blood cells that is crucial to the body’s defense against infection. Neutropenia can be caused by chemotherapy, radiation therapy or by cancer itself.

Neutrophils: This blood cell is the main cell that combats infections. Often, it is not present in sufficient quantities in patients with acute leukemia or after chemotherapy, which increased their susceptibility to infection.

Nodule: A small solid mass.



Oncologist: A physician who specializes in cancer therapy. Medical oncologists are Internists with expertise in chemotherapy and the handling of medical problems that arise during treatment for cancer. Radiation oncologists specialize in the use of radiation to treat cancer.



Palliative Treatment: The use of medical remedies to relieve pain, symptoms and/or prevent further complications rather than to cure.

Performance Status: A measurement of how well a cancer patient is functioning. Index numbers are used to document and record functional status, as opposed to other measurements that indicate the size of the tumor or the stage of the cancer. The index numbers are based on activities a patient is able to do and how well they can take care of their day to day activities without the assistance of others.

Petechiae: Pinhead-sized sites of bleeding in the skin. This type of bleeding results from a very low platelet count. These small hemorrhages are frequently seen on the legs, feet, trunk and arms.

PET Scan (Positive Emission Tomography): A body scan where small doses of radioactive material are administered. Tumors take up the material more avidly that normal tissues so a PET scan is used to see how far a cancer has spread.

Placebo: 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.

Platelet: One of the three kinds of circulating blood cells. Platelets are responsible for creating the first part of the blood clot. The normal platelet count is about 150,000 to 300,000.

Polyps: A nodular growth of tissue developing in the lining of a cavity, such as a colon, the nose or the vocal cords. Polyps may be benign or malignant.

Poorly differentiated: A tumor that under the microscope has little or only a slight resemblance to the normal tissue from the same organ.

Port: A small disc with a small center (about the size of a quarter) that is surgically placed just below the skin in the chest or abdomen. A tube coming out of the side of the port is inserted into a large vein to administer substances directly into the bloodstream. By passing a needle through the skin into the disc, fluid, drugs or blood products can be given without worrying about finding an adequate peripheral vein.

Primary tumor: The place where a cancer first starts to grow. Even if it spreads elsewhere, it is still known by the place of origin.

Prognosis: A statement about the likely outcome of disease in a particular patient. In cancer, it is based on all available information about the type of tumor, staging, therapeutic possibilities, expected results and other personal or medical factors.

Prostate: A gland located at the base of the bladder in males.

Prostate Specific Antigen (PSA): A protein in the blood produced by the prostate tissue that serves as a tumor marker.

Protocol: The outline or plan for a treatment program.



Radiation Therapy:> The use of high-energy radiation from x-rays, gamma rays, neutrons, protons or other sources to kill cancer cells or shrink tumors.

Radical Mastectomy: Removal of the entire breast along with underlying muscle and the lymph nodes of the armpit (axilla). In a modified radical mastectomy, the underlying (pectoral) muscles are left in place.

Radical Prostatectomy: Surgical removal of the prostate and the surrounding tissue.

Rectum: The last five or six inches of the colon leading to the anus.

Recurrence: The reappearance of a disease after treatment had caused it to apparently disappear.

Red blood cells (RBC): Cells in the blood that bring oxygen to tissues and take carbon dioxide from them.

Regression: The shrinkage of a cancer usually as a result of therapy.

Relapse: The reappearance of cancer after a disease-free period.

Remission: The partial or complete shrinkage of cancer usually occurring as the result of therapy. Also a period when the disease is under control. A remission is not necessarily a cure.



Sarcoma: A form of cancer that arises in the supportive tissues, such as bone, cartilage, tendons or muscle.

Sigmoidoscopy: The visual inspection of the rectum and lower colon by passing a tubular instrument called a sigmoidoscope thru the anus.

Spinal Tap: Removal of a small amount of fluid that bathes the brain and spinal cord for microscopic examination for cancer cells or other conditions.

Squamous Cell Carcinoma: A form of skin cancer that usually appears as red, scaly patches or nodules typically on the lips, face or tips of ears. It can spread to other parts of the body if untreated.

Staging: An organized process of determining how far a cancer has spread. Staging involves a physical examination, blood tests, x-rays, scans and sometimes surgery. Knowing the stage helps determine the most appropriate treatment and the prognosis.

Stem Cells: These are primitive cells in marrow that are important in making red blood cells, white blood cells and platelets. Generally, the stem cells are largely found in the marrow but some leave the marrow and circulate in the blood.

Stomatitis: Inflammation and soreness of the mouth. This is sometimes a side effect of chemotherapy or radiation.



Thrombocytopenia: An abnormally low number of platelets (thrombocytes) – less than 150,000 – due to disease, reaction to a drug or toxic reaction to treatments. Bleeding can occur if there are too few platelets, especially if the count falls to less than 20,000.

Thrush: A fungal infection of the mouth, tongue or throat. It is usually manifested by white patches of fungal colonies on the surface of the oral tissues and may be painful.

Toxicity: Refers to the undesirable and harmful side effects of a drug. Based on the toxicity, the amount of the drug a patient can safely take can be determined.

Tumor: A lump, mass or swelling. A tumor can be benign or malignant.

Tumor Marker: A chemical substance found in increased amounts in the body fluids of some cancer patients. The presence of a tumor marker in the blood for specific cancer can be an indication that cancer is present in the body. Tumor markers can be used as part of the diagnosis process but generally cannot provide a definitive diagnosis. Tumor markers are also used to monitor the progress of treatment as well as possible recurrence of cancer after treatment.



Undifferentiated: A tumor that appears “wild” under the microscope, not resembling the tissue of origin. These tumors tend to grow and spread faster than well-differentiated tumors, which do resemble the normal tissue they come from.



Vesicant drugs: Chemotherapeutic agents that can cause significant tissue irritation and soreness if they leak outside the vein during an infusion.



Well-differentiated: A tumor that under the microscope resembles normal tissue from the same organ.

White blood cells (WBC): Cells in the blood that fight infection. These are composed of monocytes, lymphocytes, neutrophils, eosinophils and basophils. The normal count is 5,000 to 10,000. It may be elevated or depressed in a wide variety of diseases. Chemotherapy and radiation usually cause low white counts.