Precancerous Conditions

Skin cancer is characterized by changes to the skin or to an existing mole. Skin cancer can begin as a noncancerous skin lesion that develops into a more dangerous cancerous lesion. Recognizing and treating precancerous skin conditions in their early stages reduces your risk of developing skin cancer.

Types of Precancerous Lesions of the Skin

Recognizing precancerous lesions is critical to the early detection of skin cancer. Perform frequent self-checks and report any new growth or change in an existing mole to your health care provider. Your doctor or dermatologist should do regular skin cancer checks, particularly if you’re at high risk.

Atypical moles called dysplastic nevi can appear anywhere on the body and are more likely than typical moles to develop into melanoma skin cancer. Changes in size or shape should be monitored as well as the appearance of asymmetrical borders or multiple colors.

Some individuals have atypical mole syndrome, a condition characterized by many moles, including both large moles and several atypical moles. A family history of atypical moles or skin cancer further increases melanoma risk.

Actinic keratosis is a skin lesion that can develop into squamous cell carcinoma if it’s left untreated. It occurs most often in older people with a history of long-term sun exposure. Actinic keratoses appear on areas of the body frequently exposed to the sun, such as the arms, face or a bald scalp. Lesions are:

  • One eighth of an inch to one inch in diameter
  • Red, pink or flesh-colored
  • Rough or sandpaper-like to the touch
  • Scaly or crusty-looking.

Treating a Precancerous Lesion

Because any lesion can become cancerous, removal is often the safest option. The appearance of actinic keratosis or an atypical mole is not itself a cause for alarm, but such lesions may be indicators of a higher risk for skin cancer.

Treatment involves the removal or destruction of precancerous cells to prevent a lesion from growing or developing into skin cancer. Your physician will recommend one of these treatments, depending on the type of lesion and its size:

  • Chemical peeling, which destroys abnormal cells and promotes new cell growth
  • Cryotherapy, which uses liquid nitrogen to freeze the lesion
  • Curettage or dermabrasion, which scrapes off abnormal cells
  • Surgical excision of the lesion and surrounding tissue
  • Topical creams, which can destroy abnormal cells.

In the case of atypical mole syndrome, individuals should be monitored closely by a dermatologist for skin cancer at least once a year, and more often if the patient is at high risk.


American Academy of Dermatology. (2010). Atypical nevus. Retrieved June 24, 2010, from

Mayo Clinic. (2009). Actinic keratosis. Retrieved June 24, 2010, from

The Skin Cancer Foundation. (2010). Actinic keratosis: The most common precancer. Retrieved June 24, 2010, from

The Skin Cancer Foundation. (2010). Dysplastic nevi: Atypical moles and risk of melanoma. Retrieved June 24, 2010, from