Squamous cell carcinoma is a very common skin cancer, second only to basal cell carcinoma. It is a malignant cancer that affects the middle layer of the skin and may occur on any part of the body, including the mucous membranes, but appears most often in areas exposed to the sun, including the face, neck, and scalp. The lower lip and the rim of the ear are also common sites for squamous cell carcinoma to appear.
Squamous cell carcinoma is relatively slow growing, although it is more aggressive than basal cell carcinoma. It has a high cure rate, about 95 percent, if caught early and treated. Because it is a more aggressive cancer, if not treated it is more likely than basal cell carcinoma to continue to grow and spread to other parts of the body, including the internal organs.
Sun exposure is the most common cause of squamous cell carcinoma. You may want to read about skin cancer early detection.
Getting older and spending time in the sun without adequately protecting your skin are the biggest risk factors for squamous cell carcinoma. This cancer can also appear in places where your skin has been scarred, burned, or exposed to certain chemicals, or at the site of a chronic skin inflammation.
Most people who get squamous cell carcinoma are diagnosed after the age of 50, and most of these cancers are found on parts of the body that have received a lot of sun exposure. These include: the rim of the ear, lower lip, face, neck, scalp, shoulders, back, arms, and hands. But occasionally this cancer will occur on what appears to be healthy, undamaged skin. It is possible that the tendency to develop squamous cell carcinoma is inherited.
Risk factors include:
- Getting older
- Excessive sun exposure.
- Having fair skin; blond or red hair; and blue, green, or gray eyes
- Overexposure to X-rays or other types of radiation
- Exposure to certain chemicals, including arsenic
- Having a chronic skin inflammation
- Having sun-damaged skin areas with a precancerous condition, such as actinic keratosis.
A note about race: African Americans are much less likely than people with fair skin and light eyes to develop skin cancer, including squamous cell carcinoma, because their skin’s pigment provides protection from the sun. However, when dark skinned people do get skin cancer, it is usually squamous cell carcinoma, which appears in areas where they have had burn injuries or inflammatory skin conditions.
These are the warning signs for squamous cell carcinoma that you should watch for:
- Any change, such as crusting or bleeding, in an existing wart, mole, scar or other skin lesion
- A persistent open sore that does not heal and bleeds, crusts, or oozes
- A scaly, persistent reddish patch with irregular borders, which may crust or bleed
- A raised growth with a central depression, which may increase rapidly in size and may occasionally bleed.
You should examine your skin regularly to watch for changes in your skin and for new suspicious growths. Call your doctor if you notice any of the changes listed above under “Symptoms.”
Your doctor will examine any suspicious lesions on your skin and do a biopsy to determine whether or not they are squamous cell carcinoma.
If you have had squamous cell carcinoma in the past, you should be especially diligent in checking your skin and seeing your doctor for regular exams, as this cancer can reoccur in new sites.