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THE SECOND MOST COMMON CANCER
Squamous cell carcinoma is the second most common skin cancer after basal cell carcinoma, affecting more than 100,000 Americans each year. It arises from the epidermis and resembles the squamous cells that comprise most of the upper layers of skin. Squamous cell cancers may occur on all areas of the body including the mucous membranes, but are most common in areas exposed to the sun.
Although squamous cell carcinomas usually remain confined to the epidermis for some time, they eventually penetrate the underlying tissues if not treated. In a small percentage of cases, they spread (metastisize) the distant tissuesand organs. When this happens, they can be fatal. Squamous cell carcinomas that metastasize most often arise from chronic inflammatory skin conditions or on the mucous membranes or lips.
Chronic exposure to sunlight causes most cases of squamous cell carcinoma. That is why tumors appear most frequently on sun-exposed parts of the body: the face, neck, bald scalp, hands, shoulders, arms, and back. The rim of the ear and the lower lip are specially vulnerable to the development of these cancers.
Squamous cell carcinomas may also occur where skin has suffered certain kinds of injury: burns, scars, long-standing sores, sites previosly exposed to X-rays or chemicals (such as arsenic and petroleum by-products).
Ocassionaly, squamous cell carcinoma arises spontaneously on what appears to be normal, healthy, undamaged skin. Some researchers believe a tendency to develp this cancer may be inherited.
Anyone with a substantial histoy of sun exposure can develop squamous cell carcinoma. But people who have fair skin, light hair, and blue, green, or gray eyes are at highest risk. Those whose occupations require long hours outdoors or who spend extensive leisure time in the sun are in particular jeopardy.
Certain precursor conditions, some of which result from extensive sun damage, are worth noting. They are sometimes associated with the later development of squamous cell carcinoma. They include:
These rough, scaly, slightly raised growths range in color from brown to red and in size up to one inch in diameter. They appear most often in older people.
This sun damage to the lips causes them to become dry, cracked, scaly, and pale to white. In affects mostly the lower lip, which typically receives more sun exposure that the upper lip
These white patches on the tongue or inside of the mouth have the potential to develop into squamous cell carcinoma.
This is considered by some to be a precancer and by others a superficial squamous cell cancer that has not yet spread. It appears as a persistent red-brown, scaly patch, which may resemble psoriasis or eczema.
Regardless of appearance, any change in a preexisting skin growth, or the development of a new growth or open sore that fails to heal, should prompt an immediate visit to a physician. If it is a precursor conditions, early treatment will prevent it from developing into a squamous cell carcinoma. Often, all that is needed is a simple surgical procedure or application of a topical chemotherapeutic agent.
After the physician´s examination, a biopsy will be performed to confirm the diagnosis of squamous cell carcinoma. This involves removing a piece of the affected tissue and examining it under a microscope. If tumor cells are present, treatment - usually surgery - is required.
Fortunately, there are several effective ways to eradicated squamous cell carcinoma. The choice of treatment is based on the type, size, location. and depth of penetration of the tumor, as well as the patient´s age and general state of heath.
Treatments can almost always be performed on an outpatient basis in a physician´s office or at a clinic. A local anesthetic is used during most procedures. Pain or discomfort is usually minimal with most techniques, and there is rarely much pain afterward.
When detected in its early stages, squamous cell carcinoma is easily treated. The larger the tumor has grown, however, the more extensive the treatment needed. Localized tumors that are not treated promptly can result in loss of an eye, ear, or nose, making early detection critical. Although squamous cell carcinoma only rarely metastasizes to vital organs, when it dos it is frequently fatal.
Because most treatment options involve cutting the skin, some scarring from removal of the tumor has to be expected. When a small tumor is removed, the result is usually cosmetically quite acceptable. Removal of a larger tumor, however, often reconstructive surgery, involving a skin graft or flap to cover the defect.
Anyone who had one squamous cell tumor faces an increased chance of developing another. That is because the damage the skin has already received from the sun cannot be reversed. Having had a basal cell carcinoma also makes it more likely that a squamous cell carcinoma will develop, because both types of skin cancer are usually caused by excessive sun exposure.
Even though a squamous cell tumor has been carefully removed, another may arise in the same place or nearby. These recurrences typically occur within the first to years after surgery. Squamous cell carcimonas on the nose, ears, and lips are specially prone to recurrence.
It is importan to periodically examine the entire body for warning signs of squamous cell carcinoma. The posibility of recurrence makes it crucial to pay particular attention to any previously treated site. Any changes noted should be shown immediately to a physician, preferably one who specializes in skin diseases. Even if no suspicious signs are noticed, sheduled follow-up visits are an essential part of post-treatment care.
The physician uses a scalpel to remove the entire growth and a surrounding border of what appears to be normal skin as a "safety margin", then closed the incision with sutures. The removed tissue is sent to the laboratory, where it is examined microscopically to ensure that all the malignant cells have been removed.
Currettage and Electroctrodesiccation
The physican scrapes the cancerous tissue away from the skin with a sharp, ring-shaped instrument called a curette, then uses an electric needle to burn the scraped area and a margin of normal skin around it. This two-step procedure is repeated several times, a deeper layer of tissue being scraped and burned each time, until the physican judges that no tumor remains.
The physician uses liquid nitrogen to destroy tumor tissue by freezing. No cutting is involved in this bloodless procedure, which may be repeated several times at the same visit to ensure total destruction of malignant cells. Easy to administer, cryosurgery is favored for patients with bleeding disorders or intolerance to anesthesia. Redness, swelling, blistering, and crusting can occur follow this treatment.
A radiation therapist directs X-ray beams at tumor. Total tumor destruction generally requires a series of treatments, usually several times a week. Radiation therapy may be used with elderly patients or with individuals whose overall heath is poor.
The surgeon successively removes very thin layers of the tumor. Each layer is immediatley examined under a microscope. Removal and microscopic examination are repeated until the site is tumor-free. Mohs micrographic surgery saves the greatest amount of healthy tissue and reduces the rate of local recurrence. It is most often used on tumors that have recurred and on those in locations that are difficult to treat (for example, the nose, ears, and around the eyes).
The laser beam is used either to excise the tumor, much as a scalpel does, or to destroy it by vaporization, in a procedure similar to electrodesiccation. The major advantage of this relatively new surgical technique is that seals blood vessels as it cuts, making it useful for patients with bleeding disorders.
