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An epithelial tumor is a cluster of irregularly-shaped cells growing specifically on the outer membrane of an organ, gland or body part. It may or may not be cancerous. Both internal and external organs have a single or multi-layer outer membrane known as an epithelium—a name that stems from the Latin prefix “epi” which means “on top of.” The epitheliums of the ovaries and salivary glands are typical areas where an epithelial tumor may be found. These tumors can also grow in the linings of breast tissue, colons, thyroid, and prostate.
If cancerous, an epithelial tumor is called a carcinoma. It is the most typical type of cancer. There are six different classes of cancerous epithelial tumors. The first is adrenocortical carcinomas, which includes any epithelial tumor found in the adrenal glands. Since the adrenal glands are responsible for regulating sex hormones such as estrogen, progesterone and testosterone, a tumor of this type in this gland can trigger a hormonal imbalance and result in a woman developing superficial male traits and a man developing female traits.
A deeper voice, more facial hair, and enlarged breasts can result from adrenal tumors. Such tumors, which are largely hereditary, also result in an overproduction of cortisol. Adrenal epithelial tumors do not respond well to chemotherapy and must be excised, medical reports suggest. If left to grow, this type of tumor frequently spreads to the lungs or liver.
The second class of these tumors consists of thyroid tumors. These cancerous growths emerge on the back of the neck in the thyroid gland. Men are more likely than women to be afflicted by this type of tumor. It is typically hard and may interfere with the function of vocal cords.
Nasopharyngeal carcinomas make up the third category of epithelial nodules. Like the thyroid tumor, this is a throat cancer. The general location for these rare growths is the top of the pharynx near the nasal cavity. Melanomas, skin cancers that afflict the cells producing melanin, are another epithelial tumor category. All other kinds of skin cancers make up the fifth class of epithelial tumors; these include squamous cell carcinomas and basal cell carcinomas.
Any other malignant epithelial tumors not included above fall into the sixth miscellaneous class. This last category includes carcinomas of the bronchi, cervix, and lungs. Cancers of the lining of the colon, bladder, and salivary glands are also included in this final catchall category. While primarily a risk for adults, more than 1,000 children are diagnosed with this type of tumor each year. The most common kind of epithelial tumors for adolescents are melanomas, adrenal tumors, and thyroid tumors.