Squamous cell carcinomas detected at an early stage and removed promptly are almost always curable and cause minimal damage. However, left untreated, they eventually penetrate the underlying tissues and can become disfiguring. A small percentage even metastasize to distant tissues and organs and can become fatal. Therefore, any suspicious growth should be seen by a physician without delay. A tissue sample (biopsy) will be examined under a microscope to arrive at a diagnosis. If tumor cells are present, treatment is required.
Fortunately, there are several effective ways to eradicate 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 health.
Treatment 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 surgical procedures. Pain or discomfort is usually minimal with most techniques, and there is rarely much pain afterwards.
Mohs Micrographic Surgery
Using a scalpel or curette (a sharp, ring-shaped instrument), the physician removes the visible tumor with a very thin layer of tissue around it. This layer is immediately checked under a microscope thoroughly. If tumor is still present in the depths or peripheries of this surrounding tissue, the procedure is repeated until the last layer viewed under the microscope is tumor-free. Mohs saves the greatest amount of healthy tissue, appears to reduce the rate of local recurrence, and has the highest overall cure rate — about 94-99 percent — of any treatment for squamous cell carcinoma. It is frequently used on tumors that have recurred, are poorly demarcated, or are in hard-to-treat, critical areas around the eyes, nose, lips, and ears, as well as the neck, hands and feet. After removal of the skin cancer, the wound may be allowed to heal naturally or be reconstructed using plastic surgery methods.
The physician uses a scalpel to remove the entire growth, along with a surrounding border of apparently normal skin as a safety margin. The wound around the surgical site is then closed with sutures (stitches). The excised tissue is then sent to the laboratory for microscopic examination to verify that all cancerous cells have been removed. The accepted cure rate for primary tumors with this technique is about 92 percent. This rate drops to 77 percent for recurrent squamous cell carcinomas.
Curettage and Electrodesiccation (Electrosurgery)
The growth is scraped off with a curette, and burning heat produced by an electrocautery needle destroys residual tumor and controls bleeding. This procedure is typically repeated a few times, a deeper layer of tissue being scraped and burned each time to help ensure that no tumor cells remain. It can produce cure rates approaching those of surgical excision for superficially invasive squamous cell carcinomas without high-risk characteristics. However, it is not considered as effective for more invasive, aggressive squamous cell carcinomas or those in high-risk or difficult sites, such as the eyelids, genitalia, lips and ears.
The physician destroys the tumor tissue by freezing it with liquid nitrogen, using a cotton-tipped applicator or spray device. There is no cutting or bleeding, and no anesthesia is required. The procedure may be repeated several times at the same session to help ensure destruction of all malignant cells. The growth becomes crusted and scabbed, and usually falls off within weeks. Redness, swelling, blistering and crusting can occur following treatment, and in dark-skinned patients, some pigment may be lost. Inexpensive and easy to administer, cryosurgery may be the treatment of choice for patients with bleeding disorders or intolerance to anesthesia. However, it has a lower overall cure rate than the surgical methods. Depending on the physician's expertise, the 5-year cure rate can be 95 percent or higher with selected, generally superficial squamous cell carcinoma; but cryosurgery is not often used today for invasive squamous cell carcinoma because deeper portions of the tumor may be missed and because scar tissue at the cryotherapy site might obscure a recurrence.
X-ray beams are directed at the tumor, with no need for cutting or anesthesia. Destruction of the tumor usually requires a series of treatments, administered several times a week for one to four weeks, or sometimes daily for onemonth. Cure rates range widely, from about 85 to 95 percent, and the technique can involve long-term cosmetic problems and radiation risks, as well as multiple visits. For these reasons, this therapy is mainly used for tumors that are hard to treat surgically, as well as patients for whom surgery is not advised, such as the elderly or those in poor health.
Photodynamic Therapy (PDT)
PDT can be especially useful for growths on the face and scalp. A photosensitizing agent, such as topical 5-aminolevulinic acid (5-ALA), is applied to the growths at the physician's office; it is taken up by the abnormal cells. The next day, the patient returns, and those medicated areas are activated by a strong light. The treatment selectively destroys squamous cell carcinomas while causing minimal damage to surrounding normal tissue. However, the treatment is not yet FDA-approved for squamous cell carcinoma, and while it may be effective with early, noninvasive tumors, overall recurrence rates vary considerably (from 0 to 52 percent), so the technique is not currently recommended for invasive squamous cell carcinoma. Redness and swelling are common side effects. After treatment, patients become locally photosensitive for 48 hours where the 5-ALA was applied, and must avoid the sun.
The skin's outer layer and variable amounts of deeper skin are removed using a carbon dioxide or erbium YAG laser. This method is bloodless, and gives the physician good control over the depth of tissue removed. It actually seals blood vessels as it cuts, making it useful for patients with bleeding disorders, and it is also sometimes used when other treatments have failed. But the risks of scarring and pigment loss are slightly greater than with other techniques, and recurrence rates are similar to those of PDT. The technique is not yet FDA-approved for squamous cell carcinoma.
5-fluorouracil (5-FU) and imiquimod, both FDA-approved for treatment of actinic keratoses and superficial basal cell carcinomas, are also being tested for the treatment of some superficial squamous cell carcinomas. Successful treatment of Bowen's disease, a noninvasive squamous cell carcinoma, has been reported. However, invasive squamous cell carcinoma should not be treated with 5-FU. Some trials have shown that imiquimod may be effective with certain invasive squamous cell carcinomas, but it is not yet FDA-approved for this purpose. Imiquimod stimulates the immune system to produce interferon, a chemical that attacks cancerous and precancerous cells.
NOT TO BE IGNORED
Squamous cell carcinomas usually remain confined to the epidermis (the top skin layer) for some time. However, the larger these tumors grow, the more extensive the treatment needed. They eventually penetrate the underlying tissues, which can lead to major disfigurement, sometimes even the loss of a nose, eye or ear. A small percentage — estimates run from 2 to almost 10 percent - spread (metastasize) to distant tissues and organs. When this happens, squamous cell carcinomas frequently can be life-threatening. About 2,500 deaths result each year in the U.S.
Metastases most often arise on sites of chronic inflammatory skin conditions and on the ear, nose, lip, and mucosal regions, including the mouth, nostrils, genitals, anus, and the lining of the internal organs.
Because most treatment options involve cutting, some scarring from the tumor removal should be expected. This is most often cosmetically acceptable when the cancer is small, but removal of a larger tumor often requires reconstructive surgery, involving a skin graft or flap to cover the defect.