Can Actinic Keratosis Turn into Cancer?

Actinic keratosis is caused by UV rays from the sun or tanning beds. It may morph into invasive skin cancer.

Actinic keratosis is caused by UV rays from the sun or tanning beds. The condition may morph into invasive squamous cell skin cancer.

Actinic keratosis (also called solar keratosis) is a skin condition characterized by scaly, rough, bumpy spots on the skin. It can progress to invasive squamous cell carcinoma, a type of skin cancer. Actinic keratosis is caused by ultraviolet (UV) light.

Symptoms of actinic keratoses include:

• Skin lesions 
  • Lesions usually occur in areas of long-term sun exposure, such as the face, ears, forearms, hands, and in bald men, the scalp
  • Lesions start as small, rough spots that have a “sandpaper-like” texture
  • Over time lesions get bigger, and become red and scaly
  • Most lesions measure about 3-10 mm, but they may grow to several centimeters in size 
  • Multiple lesions may occur in a single area, and these areas may collide and cover a larger area
• Other characteristics of the lesions may include:
  • Brown color (pigmented actinic keratosis)
  • Wasting away (atrophic)
  • Reddish or brown patches (Bowenoid)
  • Lichen planus–like rash and swelling
  • Production of a horn-like projection (cutaneous horn) above the skin surface

Actinic keratoses are caused by ultraviolet (UV) light, a component of sunlight and artificial light sources like tanning beds. 

Risk factors for developing actinic keratoses include:

• Fair skin that burns easily
• Skin that doesn’t tan easily
• Redheaded or blond hair color
• Blue or light-colored eyes
• Increased sun exposure
• Higher intensity sun exposure 
• Living in a sunny area
• Immunosuppression following organ transplantation, chemotherapy, AIDS, or leukemia
• Human papillomavirus 
• Age over 40
• A personal history of an actinic keratosis or skin cancer

The diagnosis of actinic keratosis is confirmed using a skin biopsy. A biopsy is also used to rule out invasive squamous cell carcinoma.

Another diagnostic tool for actinic keratosis is fluorescence with the use of a photosensitizing drug (methyl ester of 5-aminolevulinic acid [ALA], a precursor of protoporphyrin) commonly used during photodynamic therapy (PDT).

Treatment of actinic keratosis includes:

• Medications 
  • Topical 5-fluorouracil (5-FU) (Fluoroplex, Carac, Efudex, Tolak)
  • Imiquimod cream (Aldara 5% cream, Zyclara 3.75% cream)
  • Ingenol mebutate gel (Picato)
  • Topical diclofenac gel
• Photodynamic therapy (PDT)
  • Aminolevulinic acid (Levulan Kerastick, Ameluz)
• Surgery
  • Cryosurgery
  • Curettage, shave excision, and conventional excision (used for lesions that may indicate invasive cancer)
  • Cosmetic resurfacing procedures 
  • Medium and deep chemical peels
  • Dermabrasion
  • Ablative laser resurfacing

One study suggested that a low-fat diet may also lead to increased healing of existing actinic keratoses and decreased development of new ones.

The main complication of actinic keratosis is that lesions may progress into invasive squamous cell cancer. 

Actinic keratosis lesions are caused by ultraviolet (UV) exposure, so protecting the skin from the sun’s UV rays can help prevent the development of lesions. 

• Wear SPF 50 sunscreen, and reapply every 2 hours or after swimming or sweating
• Avoid the mid-day sun (from 10 a.m. to 4 p.m.)
• Wear sun-protective clothing such as a long-sleeved shirt, long pants, and a wide-brimmed hat
• Avoid tanning beds