When epithelial cells replicate out of control, health care providers refer to the unusual growth as an adenoma or epithelial neoplasm. Epithelial cells are found on the skin, in glands, organs, and vascular tissues, and in the lining of body cavities. Abnormal growths can form anywhere in the body and may be benign or malignant. Treatment of benign neoplasms depends on symptoms, but physicians prefer to treat malignant neoplasms more aggressively, in order to inhibit metastasis if possible.
The genetic codes in some cells do not contain the same rules of division found in normal cells. Instead of reproducing for repair or replacement purposes, an epithelial cell may continue to divide and grow beyond what is normal, becoming an epithelial neoplasm. The unusual growth may occur as an the result of an inherited trait or from exposure to environmental factors that include chemicals or radiation. Viruses can also contribute to genetic cellular abnormalities. These neoplasms might be firm or hard to the touch, and vary in coloration and size.
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Examples of benign epithelial neoplasms include simple moles on the skin and more complex uterine fibroid tumors. Benign neoplasms grow slowly while pushing normal tissue out of the way. These growths typically have well defined borders and are usually confined within a capsule. Upon microscopic examination, the cells within the mass may resemble those of surrounding tissue. Depending on the size of the neoplasm, it may include its own system of blood vessels.
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Malignant neoplasms, as opposed to those that are benign, usually have ill-defined borders, as the neoplasm often invades surrounding tissue, mixing normal cells with distinctly different ones. These tumors grow at a much faster rate than benign abnormalities, which sometime exist for years without diagnosis. Often, malignant masses have a combination of actively growing and necrotic cells, and can exhibit bleeding, inflammation, and infection. Malignant cells invade the normal tissues of glands, blood and lymph vessels, and muscles. Multiple growths may appear in the same area, but cells can also metastasize, detaching from the original tumor and traveling through the bloodstream and the lymphatic system, attaching and growing in other areas.
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Though a benign epithelial neoplasm is not usually dangerous, it might cause discomfort or interfere with organ function as the mass compresses surrounding tissue. Diagnosis and distinction between types of neoplasms may require imaging studies, needle biopsies, or surgical removal of part of the abnormal growth. Surgeons may remove a benign epithelial neoplasm that has become a nuisance, but malignant masses usually require more than on kind of therapy, depending on the location and extent of metastasis.