– Your Source for Information About Cancer Diagnosis
Glossary of Terms

Five-year survival: A description of the percentage of patients who live at least five years after their cancer is diagnosed. Five-year relative survival rates exclude patients dying of other diseases, which means that anyone who died of another cause, such as heart disease, is not counted.

Adenocarcinoma: A cancer that develops from the glandular tissue of the body.

Anemia: Anemia is a lower-than-normal number of red cells in the blood. It is a common side effect of chemotherapy treatment. Red blood cells are important because they carry oxygen from the lungs to all other cells in the body. Shortness of breath, fatigue, and weakness are signs of anemia.

Biopsy: Removal of cells or tissues from the body so that a pathologist can examine the cells or tissue under a microscope, comparing them to normal cell.

Bone scan: A bone scans use nuclear medicine imaging to spot cancer in the bone. A radioactive substance is injected into a vein and is attracted to areas of cancer. Cancer will show positive uptake of the radioactive substance. The radioactivity (the signal) is recorded by a special camera as a picture. Previous trauma or fractures can elicit a positive signal as well.

Capsular invasion: Lymph nodes and some tumors have a capsule around them like a coating or outer layer. A pathologist can determine whether or not cancer cells have invaded into or through the capsule. Lymph node capsular invasion may be important in choosing radiation as a treatment option.

Carcinoma: A type of malignancy whose cells are derived from epithelium.

Carcinoma in situ: A cancer that has not spread to other parts of the body or invaded nearby tissue. Carcinoma in situ, an early form of cancer, is highly curable.

Chemotherapy: The use of drugs to destroy cancer cells. A person on chemotherapy may take one drug or a combination of drugs. Most often these drugs are given by vein using intravenous (IV) infusion. Some can be taken by mouth or given in a shot.

Chromosomal studies: The analysis of chromosome mutations, rearrangements, and associated imbalances by a pathologist to aid in diagnosing cancer and determining treatment and prognosis.

Chromosome: A structure in the nucleus of cells that contains genes. Humans usually have 23 pairs of chromosomes. Each parent contributes one chromosome to each pair, so children get half of their chromosomes from their mothers and half from their fathers.

Clonality: Tumors often contain more than one type of cell, but their abnormal growth is usually from a single population of cells. These abnormal cells are often clonal—that is, they are descended from a single progenitor cell.

CM (centimeter): A measure of length in the metric system. There are 100 centimeters in a meter and 2½ centimeters in an inch.

Core biopsy: A type of biopsy that uses a wide needle to extract out a cylindrical piece of tissue from the body or organ for examination by a pathologist.

Counts: Counts refer to the number of white cells, red cells, hemoglobin, hematocrit, and the number of platelets.

Cytogenetic: The study of chromosomes and genes within cells.

Differentiation: The degree or extent that cancer cells resemble normal cells and the cancer resembles normal tissue. Cancer cells that closely resemble the normal cells of the tissue it is derived from are termed well-differentiated. If the cancer cells are primitive appearing or bizarre in appearance, it is termed poorly differentiated or undifferentiated.

Distant metastasis: The spread of abnormal tissue growths (malignant or nonmalignant) in parts of the body remote from the site of the primary tumor.

DNA: The biological macromolecule that encodes genetic information and is contained in the chromosome. Chemically, DNA is a polynucleotide, a polymer made up of very many subunits (deoxyribonucleotides) linked in a linear sequence. The four sub-units are A, C, G, and T.

Dose dense: The more frequent administration of chemotherapy in order to more effectively kill rapidly dividing cancer cells.

Estrogen receptor: Breast cancer is often treated differently depending on whether the cancer cells are found to be Estrogen Receptor Positive (ER+) or Negative (ER-). ER+ cells have receptors for estrogen on their surface, and their growth often requires the presence of estrogen.

FNA: FNA stands for fine-needle aspiration. This is an extremely simple technique in which a needle is inserted into a lump (tumor), and a few tens to thousands of cells are drawn up (aspirated) into a syringe. These are smeared on a slide, stained, and examined under a microscope by the pathologist. A diagnosis can often be rendered in a few minutes. Tumors of deep, hard-to-get-to structures (pancreas, lung, and liver, for instance) are especially good candidates for FNA, as the only other way to sample them is with major surgery. Such FNA procedures are typically done by a radiologist under guidance by ultrasound or computed tomography (CT scan) and require no anesthesia, not even local anesthesia.

Formalin: A colorless solution of formaldehyde in water, used chiefly as a preservative for tissue specimens. Formalin is used to preserve tissues so that they may be processed and examined under the microscope by a pathologist.

Frozen section: This technique allows a pathologist to examine histologic sections within a few minutes of removing a specimen from the patient. A tissue section is rapidly frozen, cut very thin, stained, and examined under a microscope. A skilled pathologist and a knowledgeable surgeon can work together to use the frozen section's rapid availability to the patient's great benefit during surgery.

Gene: Cells contain genes, which are pieces of DNA that contain information for making proteins. Genes contain information on hereditary characteristics such as hair color, eye color, and height, as well as whether one is at higher risk for developing certain diseases.

Genetic analysis: The study of a sample of DNA to look for mutations (changes) that may increase risk of disease or affect the way a person responds to treatment.

Grade: The degree of differentiation of tumor cells. Low grade cancers are well differentiated while high grade cancers are poorly differentiated.   There are several grading systems for cancer;  these systems divide cancers into those with:

  • Least abnormality (well differentiated)
  • Intermediate features (moderately differentiated)
  • Greatest abnormality (poorly differentiated)

A pathologist performs the grading by examining the biopsy specimen under the microscope. Knowing the grade is important because higher grade cancers tend to grow and spread more quickly and have a worse prognosis. The grade is based on features of individual cells as well as how the cells are arranged together.

Gross: The pathologist begins the examination of the specimen by dictating a description of the specimen as it looks to the naked eye. This is the gross exam or the gross. Some pathologists may refer to the gross exam as the macroscopic.

H and E: H and E stands for Hematoxylin and Eosin. This is the standard tissue stain which all pathologists use. Each tissue will stain with varying combinations of both stains. If the tissue has more of a blue to purple hue, it is termed basophilic, preferentially staining with hematoxylin. If the tissue has a pink to red hue, it is termed eosinophilic, preferentially staining with eosin. A tissue that is neither strongly eosinophilic nor basophilic is termed amphophilic.

Her-2/neu: HER-2/neu is human epidermal growth factor receptor 2, a protein that is involved in growth and replication of a cell. Some cancers have abnormal HER-2/neu proteins, which are believed to be involved in the unregulated multiplication of cancer cells.

Histology: The study or examination of tissues or cells under a microscope.

Hormone receptor test: A test to measure the amount of certain proteins, called hormone receptors, in cancer tissue. Hormones can attach to these protein receptors. The hormones cause changes to take place in the cell. A high level of hormone receptors may mean that hormones help the cancer grow.

Hormones: Chemicals secreted by glands. Hormones circulate in the bloodstream and control certain cellular actions. Some cancers need hormones to grow or have increased growth in the presence of hormones.

Immune System: The system within the body that recognizes and fights foreign cells and disease.

Immunohistochemistry: A method for staining tissue sections. Antibodies to specific proteins on cells in are used as probes to analyze tissues and identify specific types of cells, especially for diagnosis of specific types of cancer.

Immunosuppression: Suppression of the immune response may be the result of cancer, drugs/chemotherapy, or radiation.

In situ: In the normal location. An in situ tumor is a cancer that is confined to its site of origin and has not invaded neighboring tissue or gone elsewhere in the body.

In toto: To submit the entire biopsy for microscopic examination by a pathologist.

Inked margins: Often a pathologist will ink the outside of a tumor in order to accurately see the margins under the microscope. By examining the inked margins under a microscope, a pathologist can determine whether or not the entire tumor has been removed.

Invasion: When cancer cells have penetrated a border called the basement membrane and have entered the surrounding tissue.

Lymph node: Lymph nodes are small, oval glands (there was a question about the use of gland) found throughout the body. They act as filters and fight infection. Cancer cells often spread to other parts of the body through the lymphatic system.

Lymphatic invasion: When cancer cells have invaded into and are present within lymphatic vessels. This finding may be important in prognosis.

Lymphedema: A condition in which excess lymphatic fluid collects in tissues, causing swelling, pain, numbness, or a limited range of motion in the arms or legs. This often occurs when many lymph nodes are removed for the treatment or staging of cancer, or lymph nodes are treated with radiation therapy. Lymphedema most often occurs in the arms if lymph nodes under the arm are removed or radiated, or in the legs if lymph nodes in the groin are removed or radiated.

Lytic lesion: Destruction of an area of bone due to a disease process, such as cancer.

Melanoma: Melanoma is a type of cancer occurring in the cells that color the skin called melanocytes.

Malignant/Malignancy: Refers to a property of diseases in which a group of cells display uncontrolled growth (division beyond the normal limits), invasion (intrusion on and destruction of adjacent tissues), and sometimes metastasis (spread to other locations in the body via lymph.)

Margins: The edges or borders of a tumor.

Metastasis: The spread of a disease process from one part of the body to another.

Microinvasion: Invasion of in situ carcinoma into tissue that is immediately adjacent the cancer. This is the earliest stage of cancer invasion.

Microscopic: The microscopic description or the "micro" is a narrative description of the findings gained from examination of the glass slides under the microscope.

Mitotic count: Refers to the number of cells (as seen under the microscope) undergoing cell division; generally, a higher mitotic count indicates a more active aggressive cancer.

MM (millimeter): A measure of length in the metric system. A millimeter is one thousandth of a meter. There are 25 millimeters in an inch.

MRI: MRI stands for Magnetic resonance imaging. An MRI creates three-dimensional sectional images similar to CT scanning. An MRI differs from a CT scan in that it does not use ionizing radiation, but instead uses a powerful magnet to transmit radio waves through the body. Images then appear on a computer screen. Doctors use MRI to diagnose and stage cancer. A contrast medium (a dye) may be used in MRI imaging to enhance the picture.

Mutation: A change in the usual DNA sequence of a particular gene that prevents the gene from working normally. Certain cancers have specific mutations.

Myelosuppression: is the term used to Ddescribes the decrease in numbers of circulating white blood cells (WBC), red blood cells (RBC), and platelets. Myelosuppression is often a side effect of treatment with chemotherapy and/or radiation therapy.

N/C ratio: Nuclear to cytoplasmic ratio is a feature the pathologist often uses to determine the grade of a tumor. Generally, aggressive tumors have high N/C ratios.

Necrosis: Necrosis is the death of cells and/or tissue. Often, necrosis is present in areas of cancer as they out grow their blood supply.

Negative:The term negative means no. A biopsy negative for cancer means it is not cancer. A test negative for a tumor marker or a receptor means the tumor marker is not present or the cancer does not have the receptor.

Neoplasm: New growth. An abnormal proliferation of cells or tissue that usually grows more rapidly than normal. Neoplasms show partial or complete lack of structural organization and functional coordination with the normal tissue, and usually form a distinct mass of tissue, which may be either benign (benign tumor) or malignant (cancer).

Neutropenic: Refers to lower-than-normal number of neutrophils (infection-fighting white blood cells) in the blood. It is a common side effect of chemotherapy treatment. Neutrophils fight infection, so a person with a low neutrophil count will be more at risk for developing infection. Pathologists check the number of neutrophils when they measure the white blood cell count; the result is often referred to as the ANC, or absolute neutrophil count. If the neutrophil count is too low, chemotherapy may have to be postponed for a few days.

Pap test: A procedure in which cells are scraped from the cervix for examination under a microscope. It is used to detect cancer and changes that may lead to cancer. A Pap test can also show noncancerous conditions, such as infection or inflammation. Also called a Pap smear.

Particle beam radiation therapy: Particle or proton beam radiation therapy is a type of radiation therapy that uses protons as the source of radiation rather than x-rays. Protons can pass through healthy tissue without damaging it.

Pathologist: A pathologist is a physician who examines tissues and cells to identify and diagnose disease

Pathology: The study of disease. Pathology has been defined as "that branch of medicine which treats of the essential nature of disease."

Perineural invasion: When cancer cells have invaded into and around nerves. This finding may be important in prognosis.

PET scan: PET scan stands for Positron emission tomography. PET scans use whole-body imaging to allow doctors to view cellular activity of tissues inside the body. A sugar labeled with a radioactive isotope is injected into the patient’s vein. The scanner takes measurements of the cells as they use the sugar. The measurements produce a picture. Cancer cells use more of the labeled sugar than normal tissues. This increase will appear on the picture.

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

Port, port-a-cath: An implanted device through which blood may be withdrawn and chemotherapy infused without repeated needle sticks. A port is also a safer means of administering certain chemotherapeutic drugs.

Positive: The term positive means yes or affirmative. A biopsy positive for cancer means yes, it is cancer. A test positive for a tumor marker or a receptor means yes, the tumor marker is present or yes, the cancer has the receptor.

Progesterone receptor (PR): Progesterone is a protein found inside the cells of the female reproductive tissue, some other types of tissue, and some cancer cells. The hormone progesterone will bind to the progesterone receptorsinside the cells and may cause the cells to grow.

Radiation beams: Radiation therapy may come from a machine outside of the body as external beams of radiation.

Radiation burn: Sometimes, external beams of radiation can burn the skin over time. Radiation burn is very similar to a sunburn.

Radiation pneumonitis: Inflammation of lung tissue that is a side effect, or caused by, exposure to external beam radiation therapy.

Radiation seeds: Radiation therapy may come from radioactive material placed in the body near cancer cells (internal radiation therapy).A form of brachytherapy (or internal radiation treatment), radiation seed implantation delivers radiation directly to the tumor through implants (seeds) inside the body rather than from a machine outside the body (external beam radiation).

Radiation therapy: The use of radioactive substances for the treatment of diseases. Radiation therapy, sometimes called radiotherapy, x-ray therapy radiation treatment, cobalt therapy, electron beam therapy, or irradiation uses high energy, penetrating waves or particles such as x rays, gamma rays, proton rays, or neutron rays to destroy cancer cells or keep them from reproducing.

Radical resection: Surgical resection, or removal or an organ or body part, that takes the blood supply and lymph system supplying the organ along with the organ.

Receptor: A molecule inside or on the surface of a cell that binds to a specific substance and causes a specific physiologic effect in the cell. A pathologist can perform special tests to determine if a cancer has certain receptors. These tests will determine the type of treatment as well as the prognosis.

Regional lymph node: A lymph node in the area of a cancer to which cancer may spread. This spread to a regional lymph node is determined by a pathologist who examines the node under a microscope to see whether cancer cells are present.

Representative section: A section of tissue taken by the pathologist that represents what he or she saw upon gross examination. This section will be examined under the microscope in order to make a diagnosis.

Sarcoma: A type of cancer that is derived from cells that make up connective tissues, bones, and muscle.

Secondary infection: Patients with cancer who are treated with chemotherapy, radiation therapy, and/or surgery are at increased risk of developing an infection. White blood cell lines required to fight infections are markedly decreased due to chemotherapy. There are many possible causes of infection in the patient with cancer. For example, certain cancers interfere with the body's immune system and cause immunosuppression increasing the risk of infection to the patient. These cancer types include acute leukemia, chronic lymphocytic leukemia, multiple myeloma, Hodgkin disease, and non-Hodgkinlymphoma. Certain therapies used to treat cancer, such as chemotherapy (which interrupts bone marrow production of white blood cells, red blood cells, and platelets), radiation therapy, bone marrow transplantation, and treatments using corticosteroids, can lead to infection in the patient with cancer. Such infections are secondary, or due to, cancer or cancer treatments.

Sentinel lymph node: The first lymph node to receive drainage from a tumor site.

Serum tumor markers: The serum tumor marker test is 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. Tumor markers can be used for screening, diagnosis, assessing response to therapy, and monitoring for cancer recurrence.

Special stains: Staining the tissue sections with dyes gives contrast to the tissues and makes it possible to study fine details under the microscope. Special stains are used to demonstrate a specific structure, material, or cell componentfound in the tissue.

Stage: Extent or progression of a disease such as cancer. Staging determines the extent of the disease, or how far the cancer has spread. The stage is determined after performing a series of diagnostic tests, which may include x-rays, scans, and sometimes surgery. Knowing the stage of the cancer will help your doctor decide the best treatment course.

Thrombocytopenic: Thrombocytopenia is an abnormally low number of platelets (thrombocytes) circulating in the blood. Bleeding and/or bruising may occur if the platelet count is especially low. Thrombocytopenia is a common side effect of chemotherapy treatment.

Transurethral resection: A surgical procedure to remove tissue from the prostate using an instrument inserted through the urethra. Sometimes pathologists get transurethral resection of bladder tissue (also called TURP.)

Ultrasound: A radiological technique using very high frequency sound waves for imaging internal organs. The signal is emitted from a transducer placed in contact with the skin and is reflected back, detected, and used to form the image.

Vascular invasion: When cancer cells have invaded into and are present within blood vessels. This finding may be important in prognosis.


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