Home > Medical Reference > Patient Education

Ask the Expert

Get answers to your Melanoma questions.

Note: This is for informational purposes only. Doctors cannot provide a diagnosis or individual treatment advice via e-mail. Please consult your physician about your specific health care concerns.

Please install flash player to see this video.

Cancer Center Virtual Tour

Melanoma and other skin cancers - Nonmelanoma Skin Cancer

Description

An in-depth report on the causes, diagnosis, treatment, and prevention of melanoma and nonmelanoma skin cancers.

Alternative Names

Skin cancer; Squamous cell cancer; Basal cell cancer; Actinic keratosis; Nonmelanoma skin cancer

Nonmelanoma Skin Cancer:

Other types of skin cancer are referred to as nonmelanoma skin cancers The two most common types are called basal cell cancer and squamous cell cancer.

Basal Cell Cancer

Basal cell cancer starts in the lowest part of the epidermis, in round cells called basal cells. Basal cell is the most common form of skin cancer. It occurs in about 800,000 - 900,000 people every year. However, this cancer is far less likely to be fatal than melanoma. The death rate from nonmelanoma skin cancers has dropped about 30% over the past 30 years.

Basal cell cancer usually develops later in life in areas that have received the most sun exposure, such as the head, neck, back, and especially the nose. However, some basal cell cancers appear in areas not exposed to the sun.

Basal cell cancers have many different appearances:

They usually appear as a round area of thickened skin that does not change color or cause pain or itching.
Very slowly, the lesion spreads out and develops a slightly raised edge, which may be translucent and smooth. Rarely, basal cell cancers have a similar color to malignant melanomas.
Eventually, the center becomes hollowed and covered with a thin skin, which can become sore and open.
A form known as aggressive-growth basal cell cancer looks like a scar with a hard base. This type of cancer is more likely to spread and must be treated very aggressively.

Basal cell cancer is a cancerous (malignant) skin tumor involving basal skin cells. Basal cell skin cancers usually occur on areas of skin that are regularly exposed to sunlight or other ultraviolet radiation. Once a suspicious lesion is found, a biopsy is needed to diagnose basal cell cancer. Treatment varies depending on the size, depth, and location of the cancer.

Basal cell cancers are sometimes hard to tell from benign skin conditions. For instance, occasionally they arise in unexposed skin, where they may look like an ordinary mole, cyst, or pimple. They may be particularly difficult to tell apart from benign cysts when they occur near the eyes.

Usually, basal cells grow slowly. They are rarely deadly. Most basal cell cancers do not need to be treated as an emergency. However, because late treatment can cause disfigurement, they should be removed as early as possible.

Basal cell cancers that are most likely to spread include those that are larger than 1 centimeter, scar-like, and those located on the cheek, nose, neck, earlobe, eyelid, or temple.

Some studies have shown that people with basal cell cancer may be at higher risk for second cancers, including melanoma, cancer of the lip, salivary glands, larynx, lung, breast, and kidney, and non-Hodgkin's lymphoma. Those at higher risk for such cancers appear to be men and anyone diagnosed before 60 with basal cell cancer.

Squamous Cell Cancer and Bowen's Disease

Squamous cell cancer of the skin is even less common than basal cell cancers. About 200,000 to 300,000 people are diagnosed with this type of cancer each year.

Squamous cell cancer develops from flat, scale-like skin cells called keratinocytes, which lie under the top layer of the epidermis. Most squamous cell cancers occur on sun-exposed areas, especially the forehead, temple, ears, neck, and back of the hands. People who have spent considerable time sunbathing may develop them on their lower legs. Squamous cell cancers occur more often than basal cell cancers in African-Americans and Asians, and are more common in men than women.

Although squamous cell skin cancers usually can be removed completely with no risk of the cancer spreading, they are more likely to be invasive and to spread elsewhere in the body.

Types of squamous cell cancer:

Squamous cell carcinoma in situ (also called Bowen's disease) is the earliest form of this type of cancer. The cancer has not invaded surrounding tissue. Cancer areas appear as large reddish patches (often over 1 inch) that are scaly and crusted.
Invasive squamous cell carcinoma is highly likely to spread (metastasize). The skin cancer lesions can grow rapidly (over months) or slowly (over years). Eventually they break into an open wound (become ulcerated).

Click the icon to see an image of squamous cell cancer.

Getting prompt treatment is important, because squamous cell cancers are more likely than basal cell cancers to spread to local lymph nodes.

Squamous cell cancers most likely to spread include:

Deep lesions (larger than 2 cm in diameter), or patches with poorly defined borders
Large lesions
Lesions that keep returning
Squamous cell cancer on the hands, neck, earlobe, eyelid, lips, or temple
Squamous cell cancer that develops in ulcers
Squamous cell cancer that develops on skin areas that have been treated with radiation or exposed to cancer-killing chemicals (chemotherapy)

People with squamous cell cancers seem to be at higher risk for other cancers, including:

Bladder cancer
Breast cancer in women
Leukemia
Lung cancer
Melanoma
Non-Hodgkin's lymphoma
Testicular and prostate cancer in men

People who have had basal cell or squamous cell skin cancers face a two-fold increase in their risk of developing other types of cancer, such as lung, color or breast cancers. The younger people are when they get nommelanoma skin cancer, the higher their risk for developing other cancers.

Resources

www.aad.org -- American Academy of Dermatology
www.cancer.org -- American Cancer Society
www.asds.net -- American Society for Dermatologic Surgery
www.mpip.org -- Melanoma Patients' Information Page
www.cancer.gov -- National Cancer Institute
www.nccn.org -- National Comprehensive Cancer Network
www.skincancer.org -- The Skin Cancer Foundation
www.epa.gov/sunwise/uvindex.html -- UV index information

References

Abbasi NR, Yancovitz M, Gutkowicz-Krusin D, Panageas K, Googe P, King R, et al. Utility of lesion diameter in the clinical diagnosis of cutaneous melanoma. Arch Dermatol. 2008;144:469-474.

American Cancer Society. Cancer Facts and Figures 2008. Atlanta, GA: American Cancer Society; 2008.

Anderson L, Schmieder GJ, Werschler WP, et al. Randomized, double-blind, double-dummy, vehicle-controlled study of ingenol mebutate gel 0.025% and 0.05% for actinic keratosis. J Am Acad Dermatol. 2009;60(6):934-43.

Basal cell and squamous cell cancers: NCCN Medical Practice Guidelines and Oncology;V.1.2009. Accessed July 15, 2009.

Braathen LR, Szeimies RM, Basset-Seguin N, Bissonnette R, Foley P, Pariser D, et al. Guidelines on the use of photodynamic therapy for nonmelanoma skin cancer: an international consensus. International Society for Photodynamic Therapy In Dermatology, 2005. J Am Acad Dermatol. 2005;56:125-143.

Brantsch KD, Meisner C, Schonfisch B, Trilling B, Wehner-Caroli J, Rocken M, et al. Analysis of risk factors determining prognosis of cutaneous squamous-cell carcinoma: a prospective study. The Lancet Oncology. 2008;9:713-720.

Clinical practice guideline for melanoma: NCCN Medical Practice Guidelines and Oncology;V.2.2009. Accessed July 15, 2009.

Cyr PR. Atypical Moles. Am Fam Physician. 2008;78(6):735-40. Review.

deBerker D, McGregor JM, Hughes BR. Guidelines for the management of actinic keratoses. Br J Dermatol. 2007;156:222-230.

Eggermont AM, Suciu S, Santinami M, et al: EORTC Melanoma Group. Adjuvant therapy with pegylated interferon alfa-2b versus observation alone in resected stage III melanoma: final result of EORTC 18991, a randomised phase III trial. Lancet. 2008;372(9633):117-26.

Garcia C, Polette E, Crowson AN. Basosquamous carcinoma. J Am Dermatol. 2009;60(1):137-43.

Goodson AG, Grossman D. Strategies for early melanoma detection: Approaches to the patient with nevi. J Am Acad Dermatol. 2009;60(5):719-35: quiz 736-8. Review.

Guadagnolo BA, Zagars GK. Adjuvant radiation therapy for high-risk notal metastases from cutaneous melanoma. Lancet Oncol. 2009;10(4):409-16.

Hexsel, CL, Bangert SD, Hebert AA, et al. Current sunscreen issues: 2007 Food and Drug Administration sunscreen labelling recommendations and combination sunscreen/insect repellent products. J Am Dermatol. 2008;59(2):316-23. Review.

Lachiewicz AM, Berwick M, Wiggins CL, Thomas NE. Survival differences between patients with scalp or neck melanoma and those with melanoma of other sites in the surveillance, epidemiology, and end results (SEER) program. Arch Dermatol. 2008;144:515-521.

Lange JR, Fecher LA, Sharfman WH, et al. Melanoma. In: Abeloff MD, Armitage JO, Nierderhuber JE, Kastan MB, McKenna WG, eds. Abeloff's Clinical Oncology. 4th ed. Philadelphia, Pa: Churchill Livingstone; 2008:chap 73.

Lautenschlager S, Wulf HC, Pittelkow MR. Photoprotection. The Lancet [early online publication]. May 3, 2007.

Markovick SN, Erickson LA, Rao RD, Weenig RH, Pockaj BA, Bardia A, et al. Malignant melanoma in the 21st century, part 1:epidemiology, risk factors, screening, prevention, and diagnosis. Mayo Clin Proc. 2007;82:364-380.

Markovick SN, Erickson LA, Rao RD, Weenig RH, Pockaj BA, Bardia A, et al. Malignant melanoma in the 21st century, part 2: staging, prognosis, and treatment. Mayo Clin Proc. 2007;82:490-513.

Morton CA, mckenna KE, Rhodes LE:British Association of Dermatologists Therapy Guidelines and Audit Subcomittee and the British Photodermatology group. Guidelines for topical photodynamic therapy: update. Br J Dermatol. 2008;159(6):1245-66. Review.

Morton DL, Thompson JF, Cochran AJ Mozzillo N, Elashoff R, Essner R, et al. Sentinel-node biopsy or nodal observation in melanoma. N Engl J Med. 2006;355:1307-1317.

Olsen CM, Zens MS, Stukel TA, et al. Nevus density and melanoma risk in women: to test the divergent pathway hypothesis. Int J Cancer. 2009;124(4):937-44.

Ridky TW. Nonmelanoma skin cancer. J Am Acad Dermatol. 2007;57:484-501.

Savel MS, Wong SI. Review of evidence-based support for pretreatment imaging in melanoma. J Natl compr Canc netw. 2009;7(3):281-9. Review.

Suh KY, Bolognia JL. Signature nevi. J Am Acad Dermatol. 2009;60(3):508-14. Review.

Telfer NR, Colver GB, Morton CA. Guidelines for the Management of Basal Cell Carcinoma. BJD. 2008;159:35-48.

Tran KT, Wright NA, Cockerell CJ. Biopsy of the pigmented lesion-when and how. J Am Acad Dermatol. 2008;59(5):852-71. Review.

Treatment for Metastatic Ocular Melanoma. NCI Cancer Bulletin. March 7, 2006;3(10):8.

Vestergaard ME, Macaskill P, Holt PE, et al. Dermoscopy compared with naket eye examination for the diagnosis of primary melanoma: a meta-analysis of studies performed in a clinical setting. Br J Dermatol. 2008;159(3):669-76.

Warycha MA, Zakrzewski J, Ni Q, et al. Meta-analysis of sentinal lymph node positivity in thin melanoma. Cancer. 2009;115(4):869-79.

Wood GS, Gunkel J, Stewart D, et al. Nonmelanoma skin cancers: basal and squamous cell carcinomas. In: Abeloff MD, Armitage JO, Nierderhuber JE, Kastan MB, McKenna WG, eds. Abeloff's Clinical Oncology. 4th ed. Philadelphia, Pa: Churchill Livingstone; 2008:chap 74.

Zeichner JA, Stern DW, Uliasz A, et al. Placebo-controlled double-blind randomized pilot study of imiquimod 5% cream applied once per week for 6 months for the treatment of actinic keratoses. J Am Acad Dermatol. 2009;60(1):59-62.

Reviewed last on: 7/30/2009
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.