Common Cancer Definitions and Abbreviations

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S-phase fraction: A measure of the percentage of cells in a tumor that are in the phase of the cell cycle during which DNA is synthesized. The S-phase fraction may be used with the proliferative index to give a more complete understanding of how fast a tumor is growing.

Saline: A solution of salt and water.

Salpingo-oophorectomy: Surgical removal of the fallopian tubes and ovaries.

Salvage therapy: Treatment that is given after the cancer has not responded to other treatments.

Scalpel: A small, thin knife used for surgery.

Scan: A picture of structures inside the body. Scans often used in diagnosing, staging, and monitoring disease include liver scans, bone scans, and computed tomography (CT) or computerized axial tomography (CAT) scans and magnetic resonance imaging (MRI) scans. In liver scanning and bone scanning, radioactive substances that are injected into the bloodstream collect in these organs. A scanner that detects the radiation is used to create pictures. In CT scanning, an x-ray machine linked to a computer is used to produce detailed pictures of organs inside the body. MRI scans use a large magnet connected to a computer to create pictures of areas inside the body.

Scanner: In medicine, an instrument that takes pictures of the inside of the body.

Scintimammography: A type of breast imaging test that is used to detect cancer cells in the breasts of some women who have had abnormal mammograms, or who have dense breast tissue. Scintimammography is not used for screening, or in place of a mammogram. In this test, a woman receives an injection of a small amount of a radioactive substance called technetium 99, which is taken up by cancer cells, and a gamma camera is used to take pictures of the breasts. Also called Miraluma test and sestamibi breast imaging.

Screening: Checking for disease when there are no symptoms.

Screening mammogram: X-rays of the breasts taken to check for breast cancer in the absence of signs or symptoms.

Second primary cancer: Refers to a new primary cancer in a person with a history of cancer.

Second-line therapy: Treatment that is given when initial treatment (first-line therapy) doesn’t work, or stops working.

Second-look surgery: Surgery performed after primary treatment to determine whether tumor cells remain.

Secondary cancer: A term that is used to describe either a new primary cancer or cancer that has spread from the place in which it started to other parts of the body.

Segmental mastectomy: The removal of cancer as well as some of the breast tissue around the tumor and the lining over the chest muscles below the tumor. Usually some of the lymph nodes under the arm are also taken out. Also called partial mastectomy.

Seizure: Convulsion; a sudden, involuntary movement of the muscles.

Selection bias: An error in choosing the individuals or groups to take part in a study. Ideally, the subjects in a study should be very similar to one another and to the larger population from which they are drawn (for example, all individuals with the same disease or condition). If there are important differences, the results of the study may not be valid.

Selective estrogen receptor modulator: SERM. A drug that acts like estrogen on some tissues but blocks the effect of estrogen on other tissues. Tamoxifen and raloxifene are SERMs.

Sensitivity: When referring to a medical test, sensitivity refers to the percentage of people who test positive for a specific disease among a group of people who have the disease. No test has 100% sensitivity because some people who have the disease will test negative for it (false negatives).

Sensory: Having to do with the senses.

Sentinel lymph node: The first lymph node to which cancer is likely to spread from the primary tumor. When cancer spreads, the cancer cells may appear first in the sentinel node before spreading to other lymph nodes.

Sentinel lymph node biopsy: Removal and examination of the sentinel node(s) (the first lymph node(s) to which cancer cells are likely to spread from a primary tumor). To identify the sentinel lymph node(s), the surgeon injects a radioactive substance, blue dye, or both near the tumor. The surgeon then uses a scanner to find the sentinel lymph node(s) containing the radioactive substance or looks for the lymph node(s) stained with dye. The surgeon then removes the sentinel node(s) to check for the presence of cancer cells.

Sentinel lymph node mapping: The use of dyes and radioactive substances to identify the first lymph node to which cancer is likely to spread from the primary tumor. Cancer cells may appear first in the sentinel node before spreading to other lymph nodes and other places in the body.

Sepsis: The presence of bacteria or their toxins in the blood or tissues.

Septicemia: Disease caused by the spread of bacteria and their toxins in the bloodstream. Also called blood poisoning.

Sequential treatment: One treatment after the other.

SERM: See Selective estrogen receptor modulator.

Seroma: Collection of fluid under the skin after surgery.

Serous: Having to do with serum, the clear liquid part of blood.

Serum: The clear liquid part of the blood that remains after blood cells and clotting proteins have been removed.

Serum albumin: The main protein in blood plasma. Low levels of serum albumin occur in people with malnutrition, inflammation, and serious liver and kidney disease.

Serum tumor marker test: A blood test that measures the amount of substances called tumor markers (or biomarkers). Tumor markers are released into the blood by tumor cells or by other cells in response to tumor cells. A high level of a tumor marker may be a sign of cancer.

Sestamibi breast imaging: See scintimammography (also called Miraluma test).

Severe myelosuppression: Severe reduction in the numbers of red blood cells, white blood cells, and platelets in the bone marrow. Severe myelosuppression is a side effect of some cancer treatments. Also called myeloablation.

SGOT: Serum glutamic-oxaloacetic transaminase. An enzyme found in the liver, heart, and other tissues. A high level of SGOT released into the blood may be a sign of liver or heart damage, cancer, or other diseases. Also called aspartate transaminase.

SGPT: Serum glutamate pyruvate transaminase. An enzyme found in the liver and other tissues. A high level of SGPT released into the blood may be a sign of liver damage, cancer, or other diseases. Also called alanine transferase.

Shave biopsy: A procedure in which a skin abnormality and a thin layer of surrounding skin are removed with a small blade for examination under a microscope. Stitches are not needed with this procedure.

Side effect: A problem that occurs when treatment affects healthy tissues or organs. Some common side effects of cancer treatment are fatigue, pain, nausea, vomiting, decreased blood cell counts, hair loss, and mouth sores.

Significant: In statistics, describes a mathematical measure of difference between groups. The difference is said to be significant if it is greater than what might be expected to happen by chance alone. Also called statistically significant.

Silicone: A synthetic gel that is used as an outer coating on breast implants and to make up the inside filling of some implants.

Simple mastectomy: Removal of the breast. Also called total mastectomy.

Simulation: In cancer treatment, a process used to plan radiation therapy so that the target area is precisely located and marked.

Single blind study: A type of clinical trial in which only the doctor knows whether a patient is taking the standard treatment or the new treatment being tested. This helps prevent bias in treatment studies.

Skeletal: Having to do with the skeleton (bones of the body).

Skeleton: The framework that supports the soft tissues of vertebrate animals and protects many of their internal organs. The skeletons of vertebrates are made of bone and/or cartilage.

Skin graft: Skin that is moved from one part of the body to another.

Skin patch: A bandage-like patch that releases medicine into the body through the skin. The medicine enters the blood slowly and steadily.

Social worker: A professional trained to talk with people and their families about emotional or physical needs, and to find them support services.

Solid tumor: An abnormal mass of tissue that usually does not contain cysts or liquid areas. Solid tumors may be benign (not cancerous), or malignant (cancerous). Different types of solid tumors are named for the type of cells that form them. Examples of solid tumors are sarcomas, carcinomas, and lymphomas. Leukemias (cancers of the blood) generally do not form solid tumors.

Sonogram: A computer picture of areas inside the body created by bouncing high-energy sound waves (ultrasound) off internal tissues or organs. Also called an ultrasonogram.

Specificity: When referring to a medical test, specificity refers to the percentage of people who test negative for a specific disease among a group of people who do not have the disease. No test is 100% specific because some people who do not have the disease will test positive for it (false positive).

SPECT: Single-photon emission computed tomography. A special type of computed tomography (CT) scan in which a small amount of a radioactive drug is injected into a vein and a scanner is used to make detailed images of areas inside the body where the radioactive material is taken up by the cells. SPECT can give information about blood flow to tissues and chemical reactions (metabolism) in the body.

Spiral CT scan: A detailed picture of areas inside the body. The pictures are created by a computer linked to an x-ray machine that scans the body in a spiral path. Also called helical computed tomography.

Stable disease: Cancer that is neither decreasing nor increasing in extent or severity.

Stage: The extent of a cancer in the body. Staging is usually based on the size of the tumor, whether lymph nodes contain cancer, and whether the cancer has spread from the original site to other parts of the body.

Stage I breast cancer: The tumor is 2 centimeters or smaller and has not spread outside the breast.

Stage II breast cancer: Stage II is divided into stage IIA and stage IIB based on tumor size and whether it has spread to the axillary lymph nodes (the lymph nodes under the arm). In stage IIA, the cancer is either no larger than 2 centimeters and has spread to the axillary lymph nodes, or between 2 and 5 centimeters but has not spread to the axillary lymph nodes. In stage IIB, the cancer is either between 2 and 5 centimeters and has spread to the axillary lymph nodes, or larger than 5 centimeters but has not spread to the axillary lymph nodes.

Stage IIA breast cancer: Stage II breast cancer is divided into stages IIA and IIB. In stage IIA, (1) no tumor is found in the breast, but cancer is found in the axillary (under the arm) lymph nodes; or (2) the tumor is 2 centimeters or smaller and has spread to the axillary lymph nodes; or (3) the tumor is larger than 2 centimeters but not larger than 5 centimeters and has not spread to the axillary lymph nodes.

Stage IIB breast cancer: Stage II breast cancer is divided into stages IIA and IIB. In stage IIB, (1) the tumor is larger than 2 centimeters but not larger than 5 centimeters and has spread to the axillary (under the arm) lymph nodes; or (2) the tumor is larger than 5 centimeters but has not spread to the axillary lymph nodes.

Stage III breast cancer: Stage III is divided into stages IIIA and IIIB. In stage IIIA breast cancer, the cancer (1) is smaller than 5 centimeters (2 inches) and has spread to the lymph nodes in the armpit, which have grown into each other or into other structures and are attached to them; or (2) is larger than 5 centimeters and has spread to the lymph nodes in the armpit. In stage IIIB breast cancer, the cancer (1) has spread to tissues near the breast (skin, chest wall, including the ribs and the muscles in the chest); or (2) has spread to lymph nodes inside the chest wall along the breast bone.

Stage IIIA breast cancer: Stage III breast cancer is divided into stages IIIA, IIIB, and IIIC. In stage IIIA, (1) no tumor is found in the breast, but cancer is found in axillary (under the arm) lymph nodes that are attached to each other or to other structures; or (2) the tumor is 5 centimeters or smaller and has spread to axillary lymph nodes that are attached to each other or to other structures; or (3) the tumor is larger than 5 centimeters and has spread to axillary lymph nodes that may or may not be attached to each other or to other structures.

Stage IIIB breast cancer: Stage III breast cancer is divided into stages IIIA, IIIB, and IIIC. In stage IIIB, the cancer may be any size, has spread to tissues near the breast (the skin or chest wall, including the ribs and muscles in the chest), and may have spread to lymph nodes within the breast or under the arm.

Stage IV breast cancer: Cancer has spread to other organs of the body, most often the bones, lungs, liver, or brain.

Staging: Performing exams and tests to learn the extent of the cancer within the body, especially whether the disease has spread from the original site to other parts of the body. It is important to know the stage of the disease in order to plan the best treatment.

Standard of care: In medicine, treatment that experts agree is appropriate, accepted, and widely used. Health care providers are obligated to provide patients with the standard of care. Also called standard therapy or best practice.

Standard therapy: See Standard of care (also known as best practice).

Statistically significant: Describes a mathematical measure of difference between groups. The difference is said to be statistically significant if it is greater than what might be expected to happen by chance alone. Also called significant.

Stem cell: A cell from which other types of cells develop. Blood cells develop from blood-forming stem cells.

Stem cell transplantation: A method of replacing immature blood-forming cells that were destroyed by cancer treatment. The stem cells are given to the person after treatment to help the bone marrow recover and continue producing healthy blood cells.

Stereotactic biopsy: A biopsy procedure that uses a computer and a 3-dimensional scanning device to find a tumor site and guide the removal of tissue for examination under a microscope.

Stereotactic body radiation therapy: A radiation therapy technique that uses special equipment to position the patient and precisely deliver a large radiation dose to a tumor and not to normal tissue.

Stereotactic external-beam radiation: A radiation therapy technique for brain tumors that uses a rigid head frame attached to the skull. The frame is used to help aim high-dose radiation beams directly at the tumors and not at normal brain tissue. This procedure does not involve surgery. Also called stereotactic radiation therapy, stereotactic radiosurgery, and stereotaxic radiosurgery.

Stereotactic injection: A procedure in which a computer and a 3-dimensional scanning device are used to inject anticancer drugs directly into a tumor.

Stereotactic radiation therapy: Stereotactic external-beam radiation.

Stereotactic radiosurgery: Stereotactic external-beam radiation.

Stereotaxic radiosurgery: Stereotactic external-beam radiation.

Stereotaxis: Use of a computer and scanning devices to create 3-dimensional pictures. This method can be used to direct a biopsy, external radiation, or the insertion of radiation implants.

Sterile: Free from germs.

Steroid drug: A type of drug used to relieve swelling and inflammation. Some steroid drugs may also have antitumor effects.

Steroid therapy: Treatment with corticosteroid drugs to reduce swelling, pain, and other symptoms of inflammation.

Stomatitis: Inflammation or irritation of the mucous membranes in the mouth.

Subcutaneous: Beneath the skin.

Subcutaneous port: A tube surgically placed into a blood vessel and attached to a disk placed under the skin. It is used for the administration of intravenous fluids and drugs; it can also be used to obtain blood samples.

Subjective improvement: An improvement that is reported by the patient, but cannot be measured by the healthcare provider (for example, "I feel better").

Superficial: Affecting cells on the surface. Not invasive.

Support group: A group of people with similar disease who meet to discuss how better to cope with their disease and treatment.

Supportive care: Care given to improve the quality of life of patients who have a serious or life-threatening disease. The goal of supportive care is to prevent or treat as early as possible the symptoms of the disease, side effects caused by treatment of the disease, and psychological, social, and spiritual problems related to the disease or its treatment. Also called palliative care, comfort care, and symptom management.

Supraclavicular lymph node: A lymph node located above the clavicle (collarbone).

Surgeon: A doctor who removes or repairs a part of the body by operating on the patient.

Surgery: A procedure to remove or repair a part of the body or to find out whether disease is present. An operation.

Surgical oncologist: A doctor who performs biopsies and other surgical procedures in cancer patients.

Survival rate: The percentage of people in a study or treatment group who are alive for a given period of time after diagnosis. This is commonly expressed as 5-year survival.

Symptom: An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.

Symptom management: See Supportive care (also called palliative care or comfort care).

Symptomatic: Having to do with symptoms, which are signs of a condition or disease.

Syndrome: A set of symptoms or conditions that occur together and suggest the presence of a certain disease or an increased chance of developing the disease.

Synergistic: In medicine, describes the interaction of two or more drugs when their combined effect is greater than the sum of the effects seen when each drug is given alone.

Syringe: A small hollow tube used for injecting or withdrawing liquids. It may be attached to a needle in order to withdraw fluid from the body or inject drugs into the body.

Systemic: Affecting the entire body.

Systemic chemotherapy: Treatment with anticancer drugs that travel through the blood to cells all over the body.

Systemic disease: Disease that affects the whole body.

Systemic therapy: Treatment using substances that travel through the bloodstream, reaching and affecting cells all over the body.

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Tachycardia: Rapid beating of the heart, usually defined as greater than 100 beats per minute.

Tachypnea: Rapid breathing.

Targeted therapy: A type of treatment that uses drugs or other substances to identify and attack specific cancer cells without harming normal cells. A monoclonal antibody is a type of targeted therapy.

Telangiectasia: The permanent enlargement of blood vessels, causing redness in the skin or mucous membranes.

Terminal disease: Disease that cannot be cured and will cause death.

Therapeutic: Having to do with treating disease and helping healing take place.

Therapy: Treatment.

Thermography: In medicine, a procedure in which a heat-sensing infrared camera is used to record the surface heat produced by different parts of the body. Abnormal tissue growth can cause temperature changes, which may show up on the thermogram. Thermography may be used to diagnose breast cancer and other tumors.

Third-line therapy: Treatment that is given when both initial treatment (first-line therapy) and subsequent treatment (second-line therapy) don’t work, or stop working.

Thoracentesis: Removal of fluid from the pleural cavity through a needle inserted between the ribs.

Thoracic: Having to do with the chest.

Thrombocyte: A type of blood cell that helps prevent bleeding by causing blood clots to form. Also called a platelet.

Thrombocytopenia: A decrease in the number of platelets in the blood that may result in easy bruising and excessive bleeding from wounds or bleeding in mucous membranes and other tissues.

Thrombohemorrhagic event: A process that involves either a blood clot or bleeding, such as a heart attack or stroke.

Thrombophlebitis: Inflammation of a vein that occurs when a blood clot forms.

Thrombosis: The formation or presence of a blood clot inside a blood vessel.

Time to progression: A measure of time after a disease is diagnosed (or treated) until the disease starts to get worse.

Tissue: A group or layer of cells that together perform a specific function.

Tissue flap reconstruction: A flap of tissues is surgically relocated from another area of the body to the chest, and formed into a new breast mound.

TNM staging system: A system for describing the extent of cancer in a patient’s body. T describes the size of the tumor and whether it has invaded nearby tissue, N describes any lymph nodes that are involved, and M describes metastasis (spread of cancer from one body part to another).

Tomography: A series of detailed pictures of areas inside the body; the pictures are created by a computer linked to an x-ray machine.

Topical: On the surface of the body.

Topical chemotherapy: Treatment with anticancer drugs in a lotion or cream applied to the skin.

Total mastectomy: Removal of the breast. Also called simple mastectomy.

Toxic: Having to do with poison or something harmful to the body. Toxic substances usually cause unwanted side effects.

Toxin: A poison produced by certain animals, plants, or bacteria.

Trace element: A chemical found in very small amounts in a given substance. Organisms need certain trace elements to survive.

Tracer: A substance (such as a radioisotope) used in imaging procedures.

Transdermal: Through the skin.

Transformation: The change that a normal cell undergoes as it becomes malignant.

Transfusion: The infusion of components of blood or whole blood into the bloodstream. The blood may be donated from another person, or it may have been taken from the person earlier and stored until needed.

Treatment field: In radiation therapy, the place on the body where the radiation beam is aimed.

Tumor: An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancerous), or malignant (cancerous). Also called neoplasm.

Tumor board review: A treatment planning approach in which a number of doctors who are experts in different specialties (disciplines) review and discuss the medical condition and treatment options of a patient. In cancer treatment, a tumor board review may include that of a medical oncologist (who provides cancer treatment with drugs), a surgical oncologist (who provides cancer treatment with surgery), and a radiation oncologist (who provides cancer treatment with radiation). Also called a multidisciplinary opinion.

Tumor burden: Refers to the number of cancer cells, the size of a tumor, or the amount of cancer in the body. Also called tumor load.

Tumor debulking: Surgically removing as much of the tumor as possible.

Tumor infiltrating lymphocyte: A white blood cell that has left the bloodstream and migrated into a tumor.

Tumor initiation: A process in which normal cells are changed so that they are able to form tumors. Substances that cause cancer can be tumor initiators.

Tumor load: See tumor burden.

Tumor marker: A substance sometimes found in the blood, other body fluids, or tissues. A high level of tumor marker may mean that a certain type of cancer is in the body. Examples of tumor markers include CA 125 (ovarian cancer), CA 15-3 (breast cancer), CEA (ovarian, lung, breast, pancreas, and gastrointestinal tract cancers), and PSA (prostate cancer). Also called biomarker.

Tumor necrosis factor: A type of biological response modifier (a substance that can improve the body's natural response to disease). Three types of tumor necrosis factor have been identified: alpha, beta, and gamma. Tumor necrosis factor seems to play a role in the breakdown of cancer cells.

Tumor promotion: A process in which existing tumors are stimulated to grow. Tumor promoters are not able to cause tumors to form.

Tumor suppressor gene: A type of gene (unit of heredity passed from parent to offspring) that helps control cell growth. Blocking the action of tumor suppressor genes may lead to cancer.

Tumor-derived: Taken from an individual's own tumor tissue; may be used in the development of a vaccine that enhances the body's ability to build an immune response to the tumor.

Tumor-specific antigen: A protein or other molecule that is unique to cancer cells or is much more abundant in them. These molecules are usually found in the plasma (outer) membrane, and they are thought to be potential targets for immunotherapy or other types of anticancer treatment.

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Ulcer: A break on the skin or on the surface of an organ. An ulcer forms when the surface cells die and are cast off. Ulcers may be associated with cancer and other diseases.

Ulceration: The formation of a break on the skin or on the surface of an organ. An ulcer forms when the surface cells die and are cast off. Ulcers may be associated with cancer and other diseases.

Ultrasonogram: A computer picture of areas inside the body created by bouncing high-energy sound waves (ultrasound) off internal tissues or organs. Also called a sonogram.

Ultrasonography: A procedure in which high-energy sound waves (ultrasound) are bounced off internal tissues or organs and make echoes. The echo patterns are shown on the screen of an ultrasound machine, forming a picture of body tissues called a sonogram. Also called ultrasound.

Ultrasound: See ultrasonography.

Uncontrolled study: A clinical study that lacks a comparison (i.e., a control) group.

Unconventional cancer treatments: Approaches that use substances or methods of treating cancer that have not been shown to be effective by accepted scientific methods, such as carefully designed clinical trials.

Undifferentiated: A term used to describe cells or tissues that do not have specialized ("mature") structures or functions. Undifferentiated cancer cells often grow and spread quickly.

Unilateral: Having to do with one side of the body.

Unresectable: Unable to be removed with surgery.

Upper GI series: A series of x-rays of the esophagus. The x-ray pictures are taken after the person drinks a solution that contains barium. The barium coats and outlines the esophagus on the x-ray. Also called an esophagram and barium swallow.

Urea nitrogen: A chemical in the blood produced by the breakdown of protein. Urea nitrogen is removed from the blood by the kidneys. Blood urea nitrogen (BUN) tests are sometimes done to see how well the kidneys are working.

Uric acid: A waste product left over from normal chemical processes in the body and found in the urine and blood. Abnormal buildup of uric acid in the body may cause a condition called gout. Increased levels of uric acid in the blood and urine can be a side effect of chemotherapy or radiation therapy.

Urinalysis: A test that determines the content of the urine.

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Vascular endothelial growth factor: VEGF. A substance made by cells that stimulates new blood vessel formation.

VEGF: See Vascular endothelial growth factor.

Venipuncture: The puncture of a vein with a needle for the purpose of drawing blood. Also called phlebotomy.

Vital: Necessary to maintain life. Breathing is a vital function.

Vitamin: A key nutrient that the body needs in small amounts to grow and stay strong. Examples are vitamins A, C, and E.

Vomit: To eject some or all of the contents of the stomach through the mouth.

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Watchful waiting: Closely monitoring a patient's condition but withholding treatment until symptoms appear or change. Also called observation.

WBC: White blood cell. Refers to a blood cell that does not contain hemoglobin. White blood cells include lymphocytes, neutrophils, eosinophils, macrophages, and mast cells. These cells are made by bone marrow and help the body fight infection and other diseases.

White blood cell: See WBC.

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X-ray: A type of high-energy radiation. In low doses, x-rays are used to diagnose diseases by making pictures of the inside of the body. In high doses, x-rays are used to treat cancer.

X-ray therapy: The use of high-energy radiation from x-rays to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy) or from materials called radioisotopes. Radioisotopes produce radiation and can be placed in or near the tumor or in the area near cancer cells. This type of radiation treatment is called internal radiation therapy, implant radiation, interstitial radiation, or brachytherapy. Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that circulates throughout the body. X-ray therapy is also called radiation therapy, radiotherapy, and irradiation.

Xerostomia: Dry mouth. It occurs when the body is not able to make enough saliva.