Actinic cheilitis causes dryness and thickening typically along the line that separates the lips from the skin of the face, otherwise known as the lower vermillion border.
Chronic sun damage is often the cause of actinic cheilitis.
Actinic cheilitis is a precancerous condition caused by damage to the lip epithelium, which is the outer most tissue layer. The condition itself is not considered a serious health concern, but it increases the risk of skin cancer.
Most people with actinic cheilitis develop similar symptoms. About 90 percent of cases involve the lower lip, although the condition can also develop on the upper lip.
Common signs of actinic cheilitis include:
- overall dryness
- scaly plaques or scab-like lesions
- thin, delicate patches of skin
- loss of the demarcation between the lower lip and surrounding skin
- tenderness or soreness
- fissuring or skin breakage and separation
- leukokeratosis or white scaly patches
- more noticeable or prominent lip folds or lines
- tightness and wrinkled skin
Actinic cheilitis goes by several other names. Commonly used alternatives include:
- solar cheilitis
- actinic cheilosis
- actinic cheilitis with histological atypia
- actinic keratosis of the lip
- sailor's lip or farmer's lip
The lip epithelium is less pigmented and also thinner than the outer layer of the facial skin next to it. This makes it far more vulnerable to damage from the ultraviolet rays of the sun.
Excessive or chronic exposure to shortwave UV-B rays, a type of ultraviolet radiation found in sunlight, can damage lip cell DNA and cause abnormalities.
Actinic cheilitis occurs when these abnormalities cause dry, scaly patches to form on the border of the lip.
Listed below are some of the known causes of actinic cheilitis and risk factors for the condition:
- Chronic sun exposure: The more often the lips are exposed to sunlight, the more likely damage is to occur.
- Severe sunburn: Sunburn further damages skin cells and causes them to divide and regenerate, increasing the chances of cellular mutations.
- Sex: Three times more men than women develop actinic cheilitis.
- Fair skin: A majority of those with actinic cheilitis are white or fair-skinned. Rates are very high in people with albinism or those with skin pigment disorders.
- Tropical, subtropical, or desert environments: Regions near the equator have increased ultraviolet exposure. Tropical and desert regions also typically have more sunny, warm days that encourage being outdoors.
- Jobs that involve being outdoors: Jobs or hobbies that require being outdoors in the sun for more time increase the risk of sun damage. Lifeguards, construction workers, hikers, marathon runners, farmers, and sailors may have a higher chance of developing actinic cheilitis.
- Age: Usually the result of chronic or long-term sun damage, the condition mostly impacts adults.
- Smoking: Smoking or chewing tobacco can weaken the lip epithelium and make it more vulnerable to sun damage.
- Actinic prurigo: This rare, itchy photosensitivity condition causes the skin to be more sensitive to sun damage.
- Excessive alcohol use.
- Oncogenic human papillomavirus, the virus that causes warts.
- Immune disorders or immunosuppressing medications: Medications that weaken and suppress the immune system usually increase the risk of sun damage.
- Everted lower lip: When the lip is turned more outward instead of inward.
Aside from the symptoms and changes to physical appearance, actinic cheilitis also increases the risk of developing more serious health conditions.
Actinic cheilitis is considered precancerous because the mutated cells are abnormal but not yet cancerous. However, abnormal cells are usually more prone to further damage than healthy cells. When abnormal cells are damaged, the chances of more mutations and the development of cancerous ones is greatly increased.
An estimated 10 to 20 percent of actinic cheilitis cases lead to malignant carcinoma within 20 years of diagnosis. Also, between 15 and 35 percent of carcinomas caused by actinic cheilitis spread to other tissues.
Potential complications of actinic cheilitis include:
- invasive squamous cell carcinoma
- intraepidermal carcinoma, also known as squamous cell carcinoma in situ or Bowen disease
Anyone with symptoms of actinic cheilitis should talk with a doctor to rule out additional complications. A doctor should examine the lips soon after symptoms begin to establish a baseline and monitor the progression.
Actinic cheilitis is usually relatively harmless on its own, but some symptoms are considered warning signs of skin cancer.
Actinic cheilitis symptoms associated with skin cancer include:
- extreme tenderness or soreness
- an ulcer that will not heal
- continuously enlarging raised skin patches
Actinic cheilitis will require a skin biopsy. This procedure involves removing cells from the affected area for microscopic examination.
Characteristics commonly used to diagnose or confirm the condition include:
- skin dysplasia, also called abnormal skin cell growth
- inflammation in the dermis or the layer of skin tissue just below the top layer
- loss of skin elasticity
- skin thickening, usually in patches
- atrophy, also known as cell shrinkage, causing the skin to appear wrinkled
Limiting further sun exposure is usually the most important part of treatment.
Moisturizers and staying hydrated can often help reduce symptoms of dryness.
For acute cases, the affected patches can heal after following these treatment rules for a few days or weeks.
For chronic cases, it may take months for the symptoms to go away. Chronic patches need to be protected from the sun at all times.
There are some prescription medications used for the treatment of actinic cheilitis, but a dermatologist first needs to examine each lesion to see if that is going to be an effective option.
In severe cases, the affected tissues may need to be removed. Advanced options include:
- laser ablation, where a laser removes the outer layers of sun-damaged skin
- cryotherapy, where the affected patches of skin are frozen off
- vermilionectomy, where the outer layer of the lip is surgically removed
- electrocautery, where an electrical current is used to remove the abnormal patch
Regardless of the treatment plan used, cases of actinic cheilitis should be carefully monitored by a doctor. The frequency of checkups will be informed by the severity of the condition, the treatment used, and the dermatologist's recommendation. Follow-up visits could range from every couple of months to once or twice per year.
Avoiding excessive or long-term unprotected sun exposure is the best way to prevent actinic cheilitis.
Sun protection tips for the lips include:
- applying sunscreen to the body and face daily, even if not spending a long time outside
- applying lip balms or moisturizers that contain sunscreen, frequently throughout the day, especially when in the sun
- wearing a wide-brimmed hat and light, long-sleeved clothing in the sun
- growing a beard or mustache in the case of men
Other ways to reduce the risk of developing actinic cheilitis include:
- stopping smoking or chewing tobacco
- avoiding excessive alcohol use
- avoiding tanning beds
- avoiding creams, facial washes, and medications that thin the skin
- using extra caution in the sun when on immunosuppressing or anti-inflammatory medications
- treating cases of oncogenic human papillomavirus or the wart virus properly
- keeping hydrated, especially when in the sun