Glossary of Terms

Benign Tumor (mild or kind) A tumor with limited growth. It does not invade surrounding normal tissue nor does it spread (metastasize) to other tissues.
Biopsy The removal of tumor tissue for submission to a pathologist.
Cancer A malignant tumor. Some cancers may not be very aggressive being very slow to spread and others may be very aggressive spreading early in their course. (See grade).
Carcinoma A malignant tumor of the epithelium (tissue that covers the surface of a body organ- e.g. the outer layer of the skin is epithelial tissue).
Chemotherapy The use of medication (drugs) to treat a malignant tumor. The medication may be given orally or by injection. Effects on the patient are variable and depends on the medication given and the dosage used.
Clean Margins A determination by the pathologist's tissue review that the tumor tissue has been completely removed by the surgeon. This cannot be guaranteed but is determined as well as possible.
Cytology The sampling of tissue with a small needle and syringe. The sample is placed on a slide, stained and examined under a microscope. This is a simple procedure that in most cases can be done quickly and without sedation. Cytology tutorial.
Effusion Excess fluid inside a body cavity such as the abdomen or chest.
Grade A numeric way of expressing the degree of differentiation (maturity) of a tumor. Tumors are usually graded on a scale of 1 - 3. Grade 1 tumors are most like the normal surrounding tissue and are less aggressive. Grade 3 tumors are the least mature and tend to be the most aggressive.
Histopathology See Pathologist's Tissue Review.
Hypercalcemia Excess levels of calcium in the blood.
Localized Tumor A tumor that is confined to one area.
Lymph Node (lymph gland) An oval or round nodule located in many areas throughout the body that contain cells called lymphocytes. The lymph node acts as a "filter" against infectious agents such as bacteria and to some degree malignant tumor cells that come from areas of the body that are close to the lymph node.
Malignant Tumor (cancer) A tumor that invades surrounding normal tissue and can spread (metastasize) to other tissues.
Metastasis The spread of a malignant tumor to sites that are away from the primary tumor. Metastasis may be local (to a nearby lymph node) or distant (to the lungs or other organs in the body).
Neoplasm A new growth. A growth that exceeds that of surrounding normal tissue.
Oncology The study of tumors.
Palliation To decrease the size of the tumor and/or alleviate the discomfort associated with the tumor. This usually results in a comfortable and significantly increased comfortable lifespan and better quality of life over what would be obtained without treatment.
Paraneoplastic Syndromes
Effects on the body of an animal caused by the tumor but not due to the physical presence of the tumor. These effects are usually due to substances secreted by the tumor and include effects such as hypercalcemia, anemia, decreased appetite and weight loss.
Pathologist's Tissue Review The microscopic evaluation of tumor tissue that has been removed by the surgeon. The pathologist determines the type of tumor, its degree of aggressiveness (grade), and the completeness of excision.
Primary Tumor The original tumor that has developed in a patient.
Radiation Therapy The use of high energy xrays to treat a tumor. Radiation may be given from a distance (teletherapy) by a machine very much like a machine used to take ordinary radiographs or it may be given directly into the tumor (brachytherapy). Side effects occur only at the site of radiation and are usually mild. See web page on Radiation Therapy for a more complete discussion.
Regional Lymph Node(s) A lymph node(s) that is near the primary tumor.
Sarcoma A malignant tumor of connective or mesenchymal tissue. (tissue that supports outer tissues -e.g. bone or muscle).
Stage A numeric way of expressing the extent of a tumor within a patient's body. Tumors are usually staged between 1 and 4 or 5. The higher the stage, the more extensive the tumor. A stage one tumor is still localized to a single area. A stage four or five tumor has spread to distant sites in the body. For example, a stage one tumor may involve only a small area of the mouth and a stage four tumor may involve the mouth, local lymph nodes and the lungs. (See TNM)
TNM The letters used to denote the areas of involvement of a tumor while staging. T refers to the Tumor. A T1 tumor is small and not invasive. A T4 tumor is large and invasive. N refers to the Lymph nodes. N0 is a lymph node that is not involved with tumor, N1 is a freely moveable lymph node that is involved by the tumor and N3 is a non-moveable lymph node that is involved by the tumor. M refers to distant Metastasis (such as the lungs or liver). M0 means there is no metastasis and M1 means there is distant metastasis.
Tumor (neoplasm) A swelling
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