Each year in the U.S., more than 1,000,000 people are diagnosed with basal cell or squamous cell skin cancers.1 Unlike melanoma, these types of skin cancer are rarely deadly. They can, however, cause extensive tissue destruction and disfigurement, and they commonly occur in cosmetically sensitive areas such as the face.
For a majority of patients, effective initial treatment involves one of several different types of surgery. In certain cases, however, other options may be considered. Nonsurgical approaches to the treatment of basal cell and squamous cell skin cancers include radiation therapy, topical medications (medications applied to the skin), and still experimental approaches such as photodynamic therapy.
Asked why there’s a need for nonsurgical approaches to the treatment of nonmelanoma skin cancer, Dr. Anna Bar—Assistant Professor of Dermatologic Surgery at Oregon Health & Science University—responds, “Despite the proven cure rates of surgery…there’s always interest in noninvasive treatments, and there’s always progress in medicine. The nonsurgical approaches are especially useful in treating actinic keratoses, which are precursors of cancer. They’re also useful in treating some of the more superficial types of skin cancer, and they may prove to be useful in people who are too frail to even come to the doctor’s office to go through surgery.” Dr. Bar notes, however, that these other procedures haven’t been studied as extensively as surgery has been: “That’s one of the limitations of our knowledge base right now.”
Radiation therapy: Radiation therapy uses high-energy rays to damage or kill cancer cells by preventing them from growing and dividing. This treatment may be appropriate for older, debilitated patients who cannot tolerate extensive surgery or in cases where surgery may be very disfiguring.2 Radiation therapy may also be useful in the adjuvant (post-surgery) treatment of patients with aggressive skin cancers. “Radiation therapy requires multiple trips to the doctor’s office because radiation is typically not given all at once in big dose; it’s given in fractionated doses,” says Dr. Bar. She also notes that radiation therapy typically is not used to treat skin cancer in young people because of the risk of subsequent skin cancers in the radiation-treated area.
Aldara® (imiquimod): Aldara is a topical medication that stimulates the immune system to respond to the cancer.3 Aldara is approved for the treatment of actinic keratoses, superficial basal cell carcinoma, and external genital warts. A recent review of treatments for basal cell carcinoma notes that while early results for Aldara are promising, results from an ongoing study of surgery versus Aldara will provide additional important information about the effectiveness of Aldara in the treatment of superficial basal cell carcinoma.4Common side effects of Aldara include local skin reactions such as redness, flaking, erosion, swelling, itching, and scabbing or crusting.5 Less common side effects include systemic reactions such as headache or flu-like symptoms.
Topical chemotherapy: A topical form of the chemotherapy drug 5-fluorouracil (5-FU; Efudex®) is approved for the treatment of actinic keratoses and superficial basal cell carcinoma. A limitation of topical 5-FU is that it doesn’t appear to penetrate very deeply into the skin, and may not destroy deeper cancer cells.6Side effects of topical 5-FU include local reactions such as stinging, redness, swelling, and ulceration, and erosion.6
Photodynamic therapy: Photodynamic therapy involves the use of a drug (generally one that is applied directly to the skin) that collects in cells and makes them sensitive to particular wavelengths of light.7 Cancer cells tend to absorb more of the drug than normal cells. When light is then shined on the treated area, it leads to the destruction of the cancer cells.
Photodynamic therapy is approved in the United States for treatment of certain of types of actinic keratoses on the face or scalp. Although it has not been approved in the United States for the treatment of basal cell carcinoma or squamous cell carcinoma, studies suggest that it can be effective in patients with an early stage of squamous cell carcinoma (particularly patients with large or multiple lesions, or with lesions in difficult-to-treat areas) or superficial basal cell carcinoma.7 Dr. Bar cautions that cure rates for some types of basal cell carcinoma and squamous cell carcinoma appear to be poor. Common side effects include burning, itching, or stinging during the light application and for some time afterward.7 Advantages of the procedure are that it can be used to treat large areas of the skin and provides a good cosmetic outcome.
Cryotherapy: Cryotherapy involves the use of liquid nitrogen to freeze cancer cells. It is more commonly used to treat actinic keratoses than basal cell or squamous cell carcinomas. Cryotherapy is convenient and less expensive than several other treatment approaches, but it can cause loss of pigment in the treated area as well as scarring. 8
4 Bath-Hextall FJ, Perkins W, Bong J, Williams HC. Interventions for basal cell carcinoma of the skin. Cochrane Database of Systematic Reviews 2007, Issue 1. Art. No.: CD003412. DOI: 10.1002/14651858.CD003412.pub2.
8 National Cancer Institute. Skin Cancer (PDQ®): Treatment. Health Professional Version. Available at: http://www.cancer.gov/cancertopics/pdq/treatment/skin/HealthProfessional (accessed November 28, 2007)