Symptoms
By Mayo Clinic staffAlthough squamous cell carcinomas usually develop on sun-exposed skin, they can occur anywhere on your body, including inside your mouth, on your anus, and on the genitals in both men and women. The appearance of the tumors can vary, but the most common forms include:
- A firm, red nodule on your face, lower lip, ears, neck, hands or arms, that may bleed sometimes
- A flat lesion with a scaly crust on your face, ears, neck, hands or arms
- A new ulceration or raised area on a pre-existing scar or ulcer
- An ulcer or flat, white patch inside your mouth
- A red, raised patch or ulcerated sore on or in the anus or on your genitals
Squamous cell carcinomas are usually slow growing and can be difficult to spot, especially when they appear on skin that has other signs of sun damage, such as changes in pigmentation, loss of elasticity and wrinkling. They can also be mistaken for actinic keratoses — rough, scaly, dark brown or pink patches that appear after years of sun exposure. A small number of actinic keratoses eventually develop into squamous cell carcinomas.
When to see a doctor
Squamous cell carcinomas may be difficult to distinguish from normal skin, especially in their early stages. Yet the sooner they're diagnosed and treated, the better the outcome. See your dermatologist if you have a sore or scab that doesn't heal in about two months or a flat patch of scaly skin that won't go away.
- Squamous cell carcinoma. The Skin Cancer Foundation. http://www.skincancer.org/squamous-cell-carcinoma.html. Accessed Feb. 17, 2011.
- Detailed guide: Skin cancer — basal and squamous cell. American Cancer Society. http://www.cancer.org/acs/groups/cid/documents/webcontent/003139-pdf.pdf. Accessed Feb. 17, 2011.
- Lim JL. Epidemiology and clinical features of cutaneous squamous cell carcinoma. http://www.uptodate.com/home/index.html. Accessed Feb. 17, 2011.
- Public health statement for arsenic. Agency for Toxic Substances and Disease Registry. U.S. Centers for Disease Control and Prevention. http://www.atsdr.cdc.gov/PHS/PHS.asp?id=18&tid=3. Accessed Feb. 18, 2011.
- Skin cancer treatment PDQ: Professional version. National Cancer Institute. http://www.cancer.gov/cancertopics/pdq/treatment/skin/HealthProfessional/AllPages/Print. Accessed Feb. 17, 2011.
- Common medications may increase sun sensitivity. The Skin Cancer Foundation. http://www.skincancer.org/common-medications-may-increase-sun-sensitivity.html. Accessed Feb. 18, 2011.


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