What is squamous cell carcinoma?

Squamous cell carcinoma (SCC) is one of the most common forms of skin cancer. SCC is not as dangerous as melanoma, but it can spread to other parts of your body if not treated. Every year, people in Australia die from aggressive SCCs.

What are the types of squamous cell carcinoma?

Squamous cell carcinoma develops when the flat cells in the top layer of your skin (called squamous cells) grow and divide in an uncontrolled way.

You can get SCC wherever you have squamous cells — which is in many different parts of your body. However, typically they appear on parts of your skin that have been exposed to a lot of ultraviolet (UV) radiation from the sun or from tanning beds.

An early form of skin cancer, called Bowen's disease, which looks like a red, scaly patch, can also develop into an SCC if not treated.

SCC can be quite an aggressive cancer if left untreated. If you ever notice a sore, scab or scaly patch of skin that doesn’t heal within 2 months, see a doctor.

What are the symptoms of squamous cell carcinoma?

The first sign of an SCC is usually a thickened, red, scaly spot on your skin that doesn’t heal. You are most likely to find an SCC on the back of your hands, forearms, legs, scalp, ears or lips. If it’s on your lips, it can look like a small ulcer or patch of scaly skin that doesn’t go away.

Your SCC may also look like:

• a crusted sore
• a small ulcer or thickened scaly skin on the lips
• a patch of skin that's sore
• a firm, red lump
• a sore or rough patch inside your mouth
• a red, raised sore around your anus or genitals

An SCC will probably grow quickly over several weeks or months.

How is squamous cell carcinoma diagnosed?

If you think you might have an SCC, see your doctor. They may send you to see a dermatologist (a skin specialist).

If you go to a dermatologist, they will examine you and may take a small sample from the sore to test in the lab. This is known as a biopsy.

How is squamous cell carcinoma treated?

It is usually possible to completely remove your SCC. The best type of treatment for you will depend on the size and location of your SCC.

Usually, the doctor will remove your SCC using simple skin surgery. They will then look at the area under a microscope to check all the cancer has been removed. If it has spread, you might need radiotherapy afterwards.

Other ways of removing the SCC are:

• scraping it off then sealing the base of the wound with an electric needle or liquid nitrogen
• freezing it off

After treatment, you will need follow-up appointments with your doctor. You will be at greater risk of developing another skin cancer, so it’s more important than ever to protect your skin from the sun.

If your SCC has spread, you may be treated with an immunotherapy medicine given into your vein called cemiplimab.

When should I see my doctor?

Not all sores on your skin are skin cancer. But if you do develop skin cancer, the earlier it is treated, the better your outcome.

Most people find SCCs by checking their own skin. Check your skin regularly so you notice any changes.

See a doctor if:

• you have a sore that doesn't heal in 2 months
• you notice a new and unusual looking spot
• your existing spot changes in colour, size or shape
• you have a spot that is asymmetrical (irregular and not round or oval)
• you have a spot with an uneven border
• you have a spot with an unusual or uneven colour
• you have a spot that is larger than 7mm

Read the article Should I be checked for skin cancer?

Can I prevent squamous cell carcinoma?

The best way to prevent SCC is to avoid sunburn. Avoid going out in the sun when the UV Index is higher than 3, such as in the middle of the day. Seek shade, wear a hat, sunglasses and clothing that protects you from the sun, and always use an SPF30+ (or higher) sunscreen. Do not go to tanning salons.

If you are at very high risk of developing another skin cancer, your doctor may prescribe you specific vitamins.

Resources and support

• Sunsmart — a global UV app for information about sun safety, as well as up to date advice, resources and policies.
• Cancer Council Australia — for more information about sun safety and checking for and preventing skin cancers.
• The Australasian College of Dermatologists — for more information about SCCs.
• Bureau of Meteorology UV Index — for information about the UV index and sun protection times.