SCC is the second most common form of skin cancer, and is caused by uncontrolled growth of cells in the skin’s upper layers (the epidermis). SCC varies in appearance but can look like scaly red patches, open sores, elevated growths with a central depression, or warts. These lesions may crust over or bleed. These malignant tumors can grow and become disfiguring and sometimes deadly if they aren’t treated.
More than 1 million cases of SCC are diagnosed each year in the U.S., and as many as 8,800 people die from SCC. The incidence of SCC is up 200% over the last three decades in the U.S.
Like basal cell carcinoma, SCC is mainly caused by cumulative ultraviolet (UV) exposure over the course of a lifetime. Daily exposure to natural sunlight, more intense exposure in the summer months, and the UV produced by tanning beds all add to the damage that can lead to SCC.
SCC may occur on any are of the body, including mucous membranes and genitals, but typically affects areas exposed to the sun such as the rim of the ear, lower lip, face, balding scalp, hands, arms and legs. Usually the skin in these areas reveals evidence of sun damage with wrinkles, pigment changes, freckles, “age spots”, loss of elasticity, and broken blood vessels.
Following a thorough examination with a dermatology provider, the diagnosis of SCC is confirmed with a biopsy. A biopsy is obtained by numbing the skin with local anesthetic and then removing a small piece of the tumor and submitting it to a lab where it is examined under a microscope. It is absolutely necessary to take a biopsy to make the diagnosis and determine the depth of invasion, so we can make the best choice of treatment options.
SCC Treatment Options
Electrodessication and Curettage
This treatment is reserved for tumors that are very small or superficial. After injecting local anesthetic, the tumor is scraped away with a curette — an instrument with a sharp, ring-shaped tip. After scraping, the site is dessicated (burned) with an electrocautery needle. The cure rate from this procedure is above 95%. The wound takes 3-4 weeks to completely heal and will leave behind a scar the size of the tumor. This procedure is less appropriate for invasive SCC, tumors in high-risk sites, or areas where a scar would be cosmetically undesirable.
After injecting local anesthesia, the provider uses a scalpel to remove the entire tumor along with a narrow border of normal looking skin as a safety margin. The skin is then closed with stitches and the specimen is sent to the laboratory to verify that all cancer cells have been removed. Cure rates from this procedure is above 95%. If all of the cells have not been removed, it may be necessary to perform a second procedure to get clear margins.
This outpatient procedure is delivered by a radiation oncologist in an outpatient facility. X-ray beams are directed at the tumor to destroy the cancerous cells. This procedure does not require any cutting or anesthetic. Total destruction of the tumor usually requires 20-30 treatments over the course of a few weeks. This treatment is ideal for tumors in areas where it would be difficult to do surgery, and also for elderly patients or those in poor health. Cure rates for radiation are approximately 90%.
Mohs’ Micrographic Surgery
This highly specialized surgical technique is reserved for the most serious tumors in specific areas on the face. The procedure requires the Mohs’ surgeon to remove a thin layer of tissue containing the tumor. While the patient waits, the tissue is sectioned, frozen and examined by the surgeon under a microscope. If cancer is present in any of the examined sections, the procedure is repeated until the examined areas are cancer free. Once the cancer has been completely removed, the surgeon will close the skin with stitches. The cure rate with Mohs’ surgery is greater than 99%, but the procedure should be reserved for only the most serious cancers in areas that are difficult to treat by other methods.
5-fluorouracil (5-FU) and imiquimod, are FDA-approved medications for treating actinic keratoses (“pre-cancers”) and superficial basal cell carcinomas. They have also been tested for the treatment of some types of superficial SCC. Successful treatment of Bowen’s disease, a non-invasive SCC, has been reported. However, invasive SCC should not be treated with 5-FU. There is some evidence that imiquimod is useful with certain invasive SCC tumors, but it is not FDA approved for that indication.
Imiquimod is FDA approved for the treatment of superficial BCCs, with cure rates between 80 and 90%. The cream is applied to the tumor 5 times per week for at least 6 weeks. This innovative treatment works by stimulating the patient’s immune system to produce interferon, a chemical that destroys the cancer.
5-Fluorouracil has be used for many years as chemotherapy for internal cancers. A cream version of this medication has been approved by the FDA for superficial BCC, with cure rates that are similar to imiquimod. The medication is applied to the tumor twice daily for 3-6 weeks. Side effects from patient to patient, but some degree of redness, irritation and inflammation will occur.
HOW TO AVOID SCC
Most skin cancers, including SCC, are curable when detected and treated early. However, it is best to prevent them in the first place and limit risk of developing more cancers in the future. At Paladin Dermatology, we recommend the following sun safety habits:
- Avoid direct sun exposure and seek the shade, especially between 10:00am and 4:00pm.
- Do not allow your skin to get red or burned in the sun.
- Avoid tanning in the sun and never use UV tanning beds.
- Cover up with clothing, including a broad-brimmed hat and UV blocking sunglasses.
- Use a broad spectrum (UVA and UVB) sunscreen with an SPF of 15 or higher every day. For extended exposure, use a water-resistant sunscreen with a SPF of 30 or higher. Make sure to reapply sunscreen every 2 hours, and immediately after swimming or with excessive sweating.
- Apply 1 ounce (two tablespoons) of sunscreen to your entire body 30 minutes before going outside.
- Keep newborns out of the sun. Sunscreen should be used on babies over the age of 6 months.
- Examine your skin head-to-toe every month.
- See us annually for a professional skin exam, and every 6 months if you’ve previously had a skin cancer.