Treating Nonmelanoma Skin Cancer

Basal cell carcinoma and squamous cell carcinoma, which are classified as nonmelanoma skin cancers, account for approximately 96% of all diagnosed skin cancers. Usually these cancers can be cured with minor surgery that is safely performed in a medical office or outpatient setting under local anesthesia.
 
The treatment method(s) used depends on the location, size, and microscopic characteristics of the tumor as well as the patient’s overall health, medical history, and age. When the diagnosis is squamous cell carcinoma, whether or not the cancer has spread must also be considered. Large tumors may require more extensive treatment since the cancer tends to envelop much of the tissue as it grows. Some squamous cell carcinomas, especially those on the lips and ears, have a high risk of spreading. In these cases, surgery may be followed by radiation or chemotherapy.

Cure rates range from 85% to 96% if the cancer has not spread. The prognosis is poor once the cancer has spread.

Surgical and non-surgical methods used to treat these two skin cancers include:

Surgical Methods
Curettage and electrodesiccation: Often used to treat small basal cell and squamous cell tumors, this surgical procedure involves scraping the tumor with a curette (a surgical instrument shaped like a long spoon) and then using an electric needle to gently burn or “cauterize” the remaining cancer cells and a margin of normal-looking tissue. This scraping and cauterizing process is typically repeated 3 times, and the wound tends to heal without stitches.

Curettage may be used alone or as the first part of a treatment plan that uses two or more procedures. Curettage and electrodesiccation is best suited for treating a primary lesion. It also may be useful in treating some recurrent lesions; however, it is not very effective in curing recurrent lesions found within scar tissue.

Cryosurgery: Used to treat some small primary basal cell and squamous cell tumors as well as a few recurrent lesions, cryosurgery involves freezing the tumor with liquid nitrogen or another cryogen to a temperature of at least -50 degrees Celsius, which equals -58 degrees Fahrenheit. The frozen cancer cells are destroyed by the freezing and slough off, allowing the underlying normal skin to heal. Local anesthesia is usually required because this freezing is much more intense than when cryosurgery is used to treat actinic keratoses (lesions that can form after many years of sun exposure and have the potential to progress to squamous cell carcinoma).

Cryosurgery is often recommended when a patient has a bleeding disorder or another form of surgery is not advisable. However, cryosurgery is not appropriate for all skin cancers. When a tumor is large or freezing could cause a nearby area to become deformed, cryosurgery is not recommended.

The cure rate when performed by a dermatologist who is trained and experienced in cryosurgery is generally very good.

Excision: Also known as simple surgical excision, this surgical procedure is used to treat both primary and recurrent tumors. It consists of surgically removing the tumor and an area of healthy looking skin (margin) around the tumor. In some cases, the wound does not require treatment and is allowed to heal on its own. When closure is necessary, the wound may be closed with stitches, skin from another area of the body (skin graft), or healthy skin moved from a nearby area (skin flap). After surgery, the excised tissue is examined under a microscope to see if any cancer cells were present in the skin that appeared cancer free. This is the same procedure used to perform an excisional biopsy; however, a wider area of tissue is removed during simple surgical excision.

Laser surgery: Laser surgery may be used in certain cases to vaporize superficial and multiple basal cell carcinomas and to excise or destroy squamous cell carcinoma. Laser surgery does not destroy cancer cells found deeper in the skin so close follow-up with a dermatologist is important.

Mohs micrographic surgery: This highly specialized surgical technique involves first removing the visible tumor and then successive layers of skin one at a time until microscopic examination no longer reveals cancer cells. This surgery is performed while the patient is under local anesthesia. Removing and examining each layer takes about one hour, with much of this time spent looking at the removed skin. Once skin cancer is no longer visible, the surgical wound is treated as needed. Methods include allowing the wound to heal naturally, closing the wound with stitches, covering the surgical site with skin from another area of the body (skin graft), and moving healthy skin from a nearby area to cover the surgical wound (skin flap).

Mohs surgery may be an effective treatment for most skin cancers. However, the length and intensity of this surgical procedure typically limit its use to treating recurring skin cancer; larger tumors; areas where it is essential to preserve as much skin as possible, such as an ear, eyelid, nose, lip, or hand; tumors in which it is difficult to determine where the cancer ends; and sites prone to recurrence. Mohs surgery has the highest reported five-year cure rate for both basal cell and squamous cell carcinoma.

Non-surgical Methods
When one of the above surgical methods is not appropriate due to the location of the tumor, patient’s medical history, or another factor, the following treatment methods are considered. Some of these methods, such as chemotherapy and radiation, may be used after surgery to attack cancer cells that may not be removed with surgery.

Chemotherapy: If squamous cell carcinoma spreads beyond the skin to the lymph nodes or to other organs, systemic (affects entire body) chemotherapy may be used to kill the cancer cells. In systemic chemotherapy, a cancer medication is taken orally (by mouth), injected, or infused so that it can travel through the body and kill the cancer cells. Chemotherapy also destroys normal cells, and this can lead to side effects, such as nausea and hair loss. Once chemotherapy stops, the side effects usually disappear.

Immunotherapy: Immunotherapy uses the patient’s own immune system to fight the cancer. In mid-2004, a topical (applied to the skin) medication called imiquimod was approved by the U.S. Food and Drug Administration (FDA) for patients who have superficial basal cell carcinoma (one of the four types of basal cell carcinoma) and a normal immune system.

Imiquimod comes in cream form and is approved for treating superficial basal cell carcinoma (sBCC) tumors with a maximum diameter of 2.0 centimeters. Use is limited to certain areas of the body. Patients typically apply the cream once a day for approximately 5 to 7 weeks. If imiquimod is an option, your dermatologist will determine how often imiquimod should be applied. As the medication works, local skin reactions, such as redness, swelling, erosion, scabbing, scaling, and crusting occur. These are a normal and expected part of treatment. In a recent research study, a few patients with sBCC experienced headache, upper respiratory tract infection, or back pain. Patients must be willing to apply the medication as instructed and return for follow-up visits. The dermatologist will need to examine the area to see if the tumor has been destroyed. This determination should not be made by the patient, patient’s family, or friends.

It is important to know that imiquimod does not work for every patient, and another form of therapy may be necessary. The ability of imiquimod to sustain long-term clearance is still not known, and ongoing studies are evaluating the long-term effectiveness of this medication.

Radiation therapy: Radiation may be used to treat an older adult who has a large tumor; tumors that cover a large area; or a tumor that is difficult to surgically remove because of location, such as one on an eyelid, nose, or ear. Radiation therapy gradually destroys the cancer cells through repeated exposure to radiation. Usually, 15 to 30 treatments are needed.

Treatment is typically reserved for older adults because radiation has been shown to cause skin cancer years after exposure. Side effects can include the skin becoming dry, red and itchy; hairlessness near the treated area; and greater susceptibility to infection. Nausea, diarrhea, or vomiting may be seen when the treated area is near the abdomen. After treatment, fatigue can occur.

Palliative Care
The purpose of palliative care is to relieve symptoms and improve a patient’s quality of life, not cure the cancer. Patients with all stages of cancer may receive palliative care. For example, a medication used to control nausea during chemotherapy is a form of palliative care because it is treating a symptom not the cancer. Patients with advanced cancer and those who chose not to fight the cancer often receive palliative care to help control the symptoms and pain.

Investigational Methods
Researchers continue to look for more effective and safe methods for treating basal cell and squamous cell carcinoma. While many new treatments are being explored, the following methods are currently being studied in large clinical trials or have some clinical use:

Immunotherapy: Imiquimod, which is currently FDA approved for the treatment of superficial basal cell carcinoma and actinic keratoses, is being evaluated for its effectiveness in treating squamous cell carcinoma and nodular basal cell carcinoma (one of the four types of basal cell carcinoma). The ability of imiquimod to sustain long-term clearance also is being studied.

Photodynamic therapy: This form of therapy treats the tumor with a photosensitizing chemical. Treatment consists of two phases. First, the photosensitizing chemical, which is allowed to interact with the tumor for several hours, is applied. During the second phase, the treated area is then exposed to light of a certain wavelength. This may be useful for treating superficial basal cell and squamous cell carcinomas.

Follow up and Prevention: Key Part of Treatment
While both basal cell and squamous cell carcinoma have high cure rates when the cancer is detected and treated early, these skin cancers can recur. Those who have had one or more skin cancer lesion are at increased risk of developing another one within the next year or so. For these reasons, skin cancer patients should:

• Perform regular self-examinations of their skin

• Keep all appointments with a dermatologist for follow-up examinations

• Practice sun protection

If you notice a new lesion or believe that the removed tumor has recurred, see a dermatologist immediately. Early detection and removal offer the best chance for a cure.

References:
American Academy of Dermatology’s Guidelines of Care for Basal Cell Carcinoma

American Academy of Dermatology’s Guidelines of Care for Cutaneous Squamous Cell Carcinoma

Geisse, J et al. “Imiquimod 5% cream for the treatment of superficial basal cell carcinoma: Results from two phase III, randomized, vehicle-controlled studies.” Journal of the American Academy of Dermatology. 2004 May;50(5):722-33.

All content solely developed by the American Academy of Dermatology