Understanding Treatment of Non melanoma Skin Cancer

Each year in the United States, more than one million 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.

To reduce the likelihood of cancer recurrence—and the more extensive treatment that may be required to manage a recurrence—effective initial treatment is important. For a majority of patients, this involves treatment with one of several different types of surgery. “The benefits of surgery,” explains Anna Bar, MD, assistant professor of dermatologic surgery at Oregon Health & Science University, “are that it can be done in one day, it’s time tested, and it’s proven to be the most effective form of treatment with the highest cure rate.”

In certain cases other options may be considered. Nonsurgical approaches to the treatment of basal cell and squamous cell skin cancers include radiation therapy, topical medications, and still-experimental approaches such as photodynamic therapy.

What Is Nonmelanoma Skin Cancer?

Skin cancer is often divided into two broad categories: melanoma and nonmelanoma. Nonmelanoma skin cancer refers to several different types, but the most common are basal cell carcinoma and squamous cell carcinoma.

Basal cell carcinoma accounts for roughly 80 percent of all cases of nonmelanoma skin cancer.2 It most commonly develops on sun-exposed skin, with the head (particularly the nose) and the neck being the most common sites. This type of skin cancer very rarely metastasizes (spreads beyond the skin), but it can cause extensive local damage to the skin and the surrounding tissues.

Squamous cell carcinoma accounts for roughly 20 percent of all cases of nonmelanoma skin cancer.3 Squamous cell carcinoma is more likely than basal cell carcinoma to spread to lymph nodes or distant parts of the body, though this happens infrequently. Squamous cell carcinoma may be preceded by a precancerous condition known as actinic keratoses (also known as solar keratoses), which often appears as rough scaly patches on the skin.

An alarming trend in both melanoma and nonmelanoma skin cancers is that the frequency of these cancers is increasing—including the frequency in children and young adults.4,5 This increasing frequency is likely due to changing patterns of sun exposure. Sun exposure is an important risk factor for both melanoma6 and nonmelanoma skin cancer.2,3

Surgery for Nonmelanoma Skin Cancer

Surgery is the most extensively studied approach to treating nonmelanoma skin cancer, and it generally results in excellent cure rates. Furthermore, surgery for nonmelanoma skin cancer is usually done under local anesthesia. “Skin cancer surgery is one of the safest surgeries performed in the United States,” says Dr. Bar.

Depending on the size and the location of the cancer, the surgical procedure used may require only a few minutes (curettage and desiccation) or up to several hours (Mohs surgery).

Mohs Surgery

This procedure is complicated and requires expertise, but it is often recommended for the treatment of basal cell carcinoma or squamous cell carcinoma in cosmetically sensitive areas. In this procedure a doctor removes thin layers of skin one at a time and evaluates them for cancer while the patient waits. The doctor keeps removing layers of skin until he or she reaches a layer that is cancer-free. This procedure removes the least amount of normal tissue and also has the highest cure rates for both primary and recurrent cancers.7

“Mohs surgery is going to be used on areas where sparing tissue is paramount, such as the face,” explains Dr. Bar. Mohs is also a common approach to the treatment of recurrent skin cancer. “When a tumor is recurrent,” says Dr. Bar, “we often go straight to Mohs because many of the other modalities provide very poor cure rates for recurrent tumors.”

Excisional Surgery

Excisional surgery involves use of a scalpel to remove the cancer and some surrounding normal tissue. The tissue that is removed is sent to a lab, where the margins of the tissue are checked for cancer. If the margins are clear, it’s likely that the cancer was completely removed. “It’s a quicker procedure than Mohs because the patient doesn’t have to wait in the office while the tissue is checked,” says Dr. Bar. “The downside is that the patient could hear several days later that not all the cancer was removed.” The patient would then have to return for additional surgery.

Curettage and Desiccation

“This is just a five-minute procedure,” says Dr. Bar. After numbing the area, the physician scrapes the lesion and then uses an electric current to stop the bleeding and kill the remaining cancer cells. “It’s commonly used on nonaggressive subtypes of skin cancer when they’re located in lower-risk areas such as the body,” says Dr. Bar. “It can also be useful on certain areas of the face. It’s a very quick procedure, and there’s a very low risk to it. It has an acceptably good cure rate for most lesions—about 85 percent. The disadvantage is that we’re not checking the tissue; we’re just nonspecifically scraping away the skin cancer and using the cautery to destroy the remainder of the tumor cells.”

Nonsurgical Approaches to Treatment

Asked why there’s a need for nonsurgical approaches to the treatment of nonmelanoma skin cancer, Dr. Bar responds, “Despite the proven cure rates of surgery—with Mohs it’s somewhere around 98 to 99 percent for a primary basal cell or squamous cell skin cancer—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.” She also points out that people shouldn’t choose a nonsurgical approach simply because they’re afraid of surgery. “Part of the reason that people are worried about surgery is because there are many perceived risks of surgery, and some of them are misconceptions. Skin cancer surgery is extremely safe, and it’s performed almost exclusively under local anesthesia.” Additionally, reconstructive techniques used by fellowship-trained Mohs surgeons are highly advanced and designed to restore appearance after surgery.

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.8 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 a 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.9 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 information about the effectiveness of Aldara in the treatment of superficial basal cell carcinoma.10 Common side effects of Aldara include local skin reactions such as redness, flaking, erosion, swelling, itching, and scabbing or crusting.9 Less common side effects include systemic reactions such as headache or flulike symptoms.

Topical Chemotherapy

A topical form of the chemotherapy drug Efudex® (5-fluorouracil; 5-FU) 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, so it may not destroy deeper cancer cells.11 Side effects of topical 5-FU include local reactions such as stinging, redness, swelling, ulceration, and erosion.11

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.12 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 the treatment of certain 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.12 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.12 The advantages of the procedure are that it can be used to treat large areas of the skin and it 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.13

Getting the Best Care

Although nonmelanoma skin cancer is generally easier to treat that many other cancers, it should not be underestimated. “Even though nonmelanoma skin cancer is rarely deadly,” says Dr. Bar, “I’ve seen longstanding skin cancers destroy noses and eat through bone. Squamous cell carcinoma can metastasize and be deadly. It’s important to realize that we’re dealing with a cancer, and cancers can behave unpredictably; they don’t always follow the rules.” Prompt treatment by a well-qualified physician is critical to a good outcome. “A board-certified dermatologist and/or a fellowship-trained Mohs surgeon are your best resources when you’re dealing with skin cancer,” says Dr. Bar.

  1. Cancer Facts & Figures 2007. American Cancer Society Web site. Available at: Accessed December 16, 2007.
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  3. Alam M, Ratner D. Cutaneous squamous-cell carcinoma. New England Journal of Medicine. 2001;344(13):975-83.
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  7. Skin Cancer Treatment (PDQ): Health Professional Version. National Cancer Institute Web site. Available at: Accessed December 16, 2007.
  8. Neville JA, Welch E, Leffell DJ. Management of nonmelanoma skin cancer in 2007. Nature Clinical Practice Oncology. 2007;4(8):462-69.
  9. Wagstaff AJ, Perry CM. Topical imiquimod: A review of its use in the management of anogenital warts, actinic keratoses, basal cell carcinoma and other skin lesions. Drugs. 2007;67(15):2187-210.
  10. Bath-Hextall FJ, Perkins W, Bong J, Williams HC. Interventions for basal cell carcinoma of the skin. Cochrane Database of Systematic Reviews. 2007;(1):CD003412.
  11. Lee S, Selva D, Huilgol SC, Goldberg RA, Leibovitch I. Pharmacological treatments for basal cell carcinoma. Drugs. 2007;67(6):915-34.
  12. Fien SM, Oseroff AR. Photodynamic therapy for non-melanoma skin cancer. Journal of the National Comprehensive Cancer Network. 2007;5(5):531-40.
  13. Skin Cancer Treatment (PDQ): Patient Version. National Cancer Institute Web site. Available at: Accessed December 16, 2007.
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