Definition of Premalignant
Premalignant:
Pertaining to tissue that is not yet malignant, but is poised to become malignant. Appropriate clinical and laboratory studies are designed to detect premalignant tissue while it is still in a premalignant stages. A large battery of techniques are generally available to remove or kill the tissue, thereby preventing the development of cancer. The proper treatment method depends on the particular premalignant tissue involved. Following are a few examples of premalignant growths:
Colon Growth: Polyp
A premalignant growth called a polyp occurs in the
colon in two forms. One form has a stem with an umbrella-like top. This type of polyp resembles a mushroom. The second form has no stalk, only the umbrella top. Although the causes of most polyps are not yet fully fathomed, it is known that an inherited disease called familial adenomatous polyposis (FAP) can lead to the development of hundreds of colon polyps in a person with FAP.
Skin Growth: Actinic Keratosis
Premalignant tissue on the skin occurs as a scaly
patch slightly elevated above the surface. The patch, usually red or brown,
is rough and horny. Prolonged and frequent exposure to sunlight is the
primary cause of this type of premalignant condition. The technical term
for such a patch is actinic keratosis. ("Actinic" refers to sunlight or
radiation; for example, an actinic burn would be caused by exposure to the
sun's rays or to X-rays, not by exposure to fire. "Keratosis" refers to the
rough, horny appearance of tissue.)
Cervix Growth: Dysplasia
Premalignant tissue in the cervix, the neck of the
womb, may involve cells that begin to alter their shape and size, a condition
known as dysplasia. ("Dys-" means "bad" and "-plasia" means "condition.")
Such cells are present only in the outer layer of tissue. If those cells
become cancerous, they attack the inner, deeper tissues. Factors that contribute
to the development of cervical growths include sexual activity early in life,
frequent sexual activity with many partners, herpes infections, inattentive
health care, and multiparity (being the mother of more than one child).
Lung Growth: Squamous Metaplasia
Premalignant tissue in the lung can occur in the
form of squamous metaplasia -- flat, scaly, plate like cells with irregular
shapes . ("Squamous" means "scaly" and "meta-" means "change.") If these
cells turn cancerous, they invade deep tissue. Chronic damage to
the lungs can contribute to the development of lung growths.
Breast Growths: Abnormal Cells in Milk Ducts
Premalignant tissue may occur in the milk ducts of the breasts in the form of cells that grow abnormally. Advancing age, a family history of breast tumors, diabetes, high blood pressure, exposure to radiation, and first-time motherhood after age 40 have all been implicated
as risk factors for breast tumors.
Mouth Growths: Leukoplakia and Erythroplakia
Premalignant tissue in the mouth may appear as patches of
white tissue (leukoplakia) or red tissue (erythroplakia). These
formations appear on mucous membranes. If they do not go away after 10
to 20 days, the patient should have a doctor take a tissue sample (biopsy)
for analysis.
Last Editorial Review: 1/26/2000 7:50:00 AM
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