Squamous cell carcinoma of the lip often develops from a precancerous lesion called actinic cheilitis. Both conditions can cause changes in the color and texture of your lip. Your outlook is best with an early diagnosis and treatment.

Skin cancer is the most common type of cancer in the United States. Most diagnoses of skin cancer are squamous cell carcinoma or basal cell carcinoma.

Skin cancers typically start on skin that’s frequently exposed to the sun, such as the face, neck, and arms. Sometimes, they may develop from a precancerous lesion.

Actinic cheilitis is a type of precancerous lesion that can form on your lips. Over time, it may develop into squamous cell carcinoma.

Want to know more about actinic cheilitis and squamous cell carcinoma? Keep reading below to learn more about each condition, their signs and symptoms, and how they’re diagnosed and treated.

Actinic cheilitis (AC) is a precancerous lesion that affects the lips. It’s similar to another precancerous lesion called actinic keratosis, which can occur on other parts of the body.

AC occurs due to damage from excess exposure to ultraviolet (UV) radiation, such as from the sun. If left untreated, it can turn into squamous cell carcinoma.

The exact prevalence of AC isn’t known. Some researchers have estimated that it happens at a prevalence of 0.3% to 3.7%. However, a study in northwestern Spain reported a prevalence of 31.3% in adults 45 and older.

Squamous cell carcinoma (SCC) is a common type of skin cancer. It begins in squamous cells, which are flat cells found in the upper layer of your skin (epidermis).

SCC happens due to damage that accumulates over time from excess UV radiation exposure. On the lips, it can develop from an AC lesion.

It’s estimated that up to 1 million diagnoses of SCC are made in the United States each year. A 2023 study identified 8,625 diagnoses of SCC on the lips between the years 2000 and 2019.

What are the risk factors for actinic cheilitis and squamous cell carcinoma?

Because they have a common cause, AC and SCC share risk factors. These include:

  • excess exposure to UV radiation
  • geographical factors, specifically living in areas with higher UV radiation exposure, such as those:
    • close to the equator
    • at a high altitude
    • near to reflective surfaces like water, snow, or sand
  • occupations associated with high levels of UV radiation exposure, such as farmers, fishermen, or construction workers
  • older age
  • male sex
  • lighter skin, hair, and eyes
  • a previous history of skin precancers or cancers

The outlook for any precancer or cancer is best when it’s found and treated early. Because of this, it’s important to be able to recognize changes on or around your lips that could signal AC or SCC.

Actinic cheilitis symptoms and signs

AC most often affects the lower lip and is often painless. You may notice changes like:

  • an area of your lip that’s persistently dry or rough to the touch
  • a part of your lip that’s discolored, typically paler or yellow in color
  • thickened areas that may be scaly or crusty or appear as white patches
  • blurring of the border between the skin of your lip and the skin of your face
  • more noticeable folds and lines around your lips
  • tenderness, redness, or swelling

Squamous cell carcinoma symptoms and signs

The potential signs and symptoms of SCC on your lips include:

  • a sore or ulcer on your lip that doesn’t heal
  • a persistently scaly spot on your lip
  • a thickened area or a lump on your lip that you can feel
  • swelling, bleeding, or pain affecting your lip that’s not due to a known cause

Check out the pictures below to get a better idea of what AC and SCC can look like.

A doctor can diagnose AC by examining the lesion on your lip. However, because AC and SCC can appear very similar, they may still want to take a skin biopsy to check for cancer.

During a biopsy, a doctor will remove a small sample of tissue from your lip. Local anesthesia will be used for this, so you won’t feel any pain while the biopsy is collected.

Your biopsy sample is then sent to a lab to be analyzed. A specialized doctor called a pathologist will look at it under a microscope to check for signs of cancer.

If cancer cells are found in your biopsy sample, imaging tests may be ordered to check how far the cancer has spread.

AC and SCC can be treated differently. Below, we’ll explore the types of treatment that may be used for each.

Actinic cheilitis treatment

If you have AC, your doctor will want to remove the precancerous area on your lip to help prevent it from developing into SCC. There are a couple of ways that they may do this.

The first is to use nonsurgical treatments to destroy the precancerous cells without affecting your lips too much. Phototherapy and topical creams containing 5-fluorouracil or imiquimod are examples of nonsurgical treatments for AC.

Surgical treatments may include destroying the precancerous cells with extreme cold or with heat from a laser (ablation). A vermilionectomy, or lip shave, removes the red surface of the lip and may be recommended in some situations.

The treatment used depends on the extent of the lesion and how abnormal its cells appear under a microscope. Nonsurgical treatments may be used for mild lesions, while surgical treatments may be used in moderate to severe cases.

Squamous cell carcinoma treatment

Surgery is one of the main treatments used for SCC. For lesions affecting more sensitive areas like the face, Mohs surgery will likely be used. This approach aims to remove all of the cancer while keeping healthy skin intact.

In Mohs surgery, the lesion and a small area of healthy skin are removed. This will then be checked in a lab while you wait. If cancer cells are still present, the surgeon will continue to remove small areas of skin until no cancer can be seen.

SCC that has spread deeper into the tissue of your lip may need more extensive surgery than Mohs.

Radiation therapy is also a potential treatment option. A doctor may recommend this treatment if you cannot have surgery or if they’re concerned that some cancer still remains after surgery.

If SCC has spread further than your lips, you may need additional treatments, such as:

If you’ve been diagnosed with AC or SCC, you may be wondering what your outlook is.

Outlook for people with actinic cheilitis

A 2021 review of 36 studies looked into the outcomes of AC. It found that laser ablation and vermilionectomy had the best clinical and aesthetic outcomes.

These two treatment methods were also associated with fewer recurrences of AC. Meanwhile, the researchers noted that phototherapy was linked with more AC recurrences.

Early treatment is important to prevent AC from developing into SCC. It’s estimated that AC progresses to SCC in 6% to 10% of cases, although this percentage is higher, 10% to 30%, in some reports.

Regardless of the exact progression rate, about 95% of SCCs develop from an existing AC.

Outlook for people with squamous cell carcinoma

The outlook for SCC is best when it’s diagnosed and treated early. Delaying treatment can mean that the cancer has a higher chance of growing larger and spreading further in the body, which can make treating it effectively more difficult.

SCC on the lips may spread faster than when it’s on other areas of the skin. A 2021 study notes that the rate at which lip SCC spreads (metastasizes) is four times higher than in other skin areas.

It can be difficult to tell the difference between AC and SCC. That’s why it’s important to get medical help if you’ve developed an unusual lesion on your lip.

AC or SCC lesions don’t go away and may change over time. Pain, bleeding, or changes in the color or texture of your lip are all further signs it’s time to see a doctor.

Going to a primary care provider is a good first step. They may refer you to a dermatologist, who is a doctor who specializes in skin health.

Both precancerous lip lesions and lip cancer are highly preventable. You can reduce your risk by limiting your exposure to UV radiation. Consider the following:

  • using lip care products with an SPF 30 or higher when you’re going to be outside and reapplying it regularly
  • finding shade when you need to be outside during the day
  • wearing a wide-brimmed hat or sunglasses that can protect your face from the sun
  • avoiding tanning beds
  • performing monthly skin self-exams, including those on your lips
  • seeing a dermatologist yearly for a skin exam

Now let’s look at some answers to frequently asked questions about lip lesions and lip cancer.

How fast can lip cancer spread?

According to the American Academy of Dermatology, SCC often grows slowly. Some research notes that SCC that grows rapidly is associated with a poorer outlook. Additionally, SCC impacting the lips may spread faster.

Is cancer in the lips curable?

Yes, lip cancer is highly curable if it’s found early. Early stage lip cancers are often smaller and easier to remove completely than other skin cancers.

SCC can develop from AC, which is a precancerous lip lesion. Both conditions are caused by damage from exposure to UV radiation.

The treatment for AC can be nonsurgical or surgical. However, surgery is the main form of treatment for SCC.

Outlook for AC and SCC is best with early diagnosis and treatment. Both types of lesions can appear similar, so be sure to see a doctor if you notice a persistent lip lesion associated with bleeding, pain, or changes in color or texture.