Basal Cell Carcinoma

Ninety percent of all skin cancers in the United States are basal cell carcinoma. This type of cancer typically appears on the head, face, neck, hands, or arms. It can often be removed completely during a biopsy, with no further treatment required. While basal cell carcinoma is curable in most cases, people who have had this type of skin cancer have a higher-than-average risk of developing other skin cancers.

 

What Is Basal Cell Carcinoma?

There are several types of skin cancer. The most common forms are basal cell carcinoma followed by squamous cell carcinoma. These forms of cancer are often referred to as nonmelanoma skin cancer to differentiate them from a third type of cancer called melanoma. Melanoma is less common, more deadly, and more likely to spread throughout the body.
 
Ninety percent of all skin cancers in the United States are basal cell carcinoma. This type of cancer grows slowly and rarely spreads to other areas. Basal cell carcinoma can occur anywhere, but is typically found on the:
 
  • Head
  • Face
  • Neck
  • Hands
  • Arms.
 
Most basal cell carcinomas can be cured. However, people with this type of skin cancer have a higher risk for developing other skin cancers.
 

Understanding the Skin

The skin is the body's largest organ. The skin:
 
  • Protects against heat, sunlight, injury, and infection
  • Helps control body temperature
  • Stores water, fat, and vitamin D.
 
The skin has several layers, but the two main layers are the epidermis (the upper or outer layer) and the dermis (the lower or inner layer).
 
Skin cancer begins in the epidermis, which is made up of three kinds of cells, including:
 
  • Squamous cells: Thin, flat cells that form the top layer of the epidermis.
  • Basal cells: Round cells located under the squamous cells.
  • Melanocytes: Found in the lower part of the epidermis, these cells make melanin, the pigment that gives skin its natural color. When skin is exposed to the sun, melanocytes make more pigment, causing the skin to tan, or darken.
 

Risk Factors

Basal cell carcinoma risk factors include:
 
  • Being exposed to a lot of natural or artificial sunlight
  • Having scars or burns on the skin
  • Being exposed to arsenic
  • Having chronic skin inflammation or skin ulcers
  • Being treated with radiation
  • Taking immunosuppressive drugs (for example, after an organ transplant)
  • Having actinic keratosis
  • Having a fair complexion (blond or red hair, fair skin, green or blue eyes, history of freckling).
 

Symptoms

Not all changes in the skin are a sign of basal cell carcinoma, but a doctor should be consulted if changes in the skin are seen (see Signs of Skin Cancer).
 

Diagnosing Basal Cell Carcinoma

Tests or procedures that examine the skin are used to detect and diagnose basal cell carcinoma. Common procedures include a skin examination or a biopsy.
 
Skin Examination
During a skin examination, a doctor or nurse will check the skin for bumps or spots that look abnormal in color, size, shape, or texture.
 
Biopsy
In a biopsy, all or part of the abnormal-looking growth is cut from the skin and viewed under a microscope by a pathologist to see if cancer cells are present. The three types of skin biopsies are:
 
  • Shave biopsy: A sterile razor blade is used to shave off the abnormal-looking growth
  • Excisional biopsy: A scalpel is used to remove the entire growth
  • Punch biopsy: A special instrument called a punch or a trephine is used to remove a circle of tissue from the abnormal-looking growth.
 

Treatment Options

Treatment for most basal cell carcinoma involves some kind of surgery. Generally, the cancer is removed completely during biopsy and no further treatment is required. In most cases, basal cell carcinomas are curable, but people who have had the disease have a higher-than-average risk of developing another basal cell carcinoma.
 

Preventing Basal Cell Carcinoma

The best way to prevent basal cell carcinoma is to protect yourself from the sun. Doctors suggest that people of all ages limit their time in the sun and avoid other sources of ultraviolet (UV) radiation. Recommendations for basal cell carcinoma prevention include:
 
  • It is best to stay out of the midday sun (from mid-morning to late afternoon) whenever you can. You also should protect yourself from UV radiation reflected by sand, water, snow, and ice. UV radiation can go through light clothing, windshields, windows, and clouds.
 
  • Wear long sleeves and long pants of tightly woven fabrics, a hat with a wide brim, and sunglasses that absorb UV.
 
  • Use sunscreen lotions. Sunscreen may help prevent basal cell carcinoma, especially broad-spectrum sunscreen (to filter UVB and UVA rays) with a sun protection factor (SPF) of at least 15. However, it is still important to avoid the sun and wear clothing to protect your skin.
 
  • Stay away from sunlamps and tanning booths.
 

A Summary of Basal Cell Carcinoma

Key points to keep in mind regarding basal cell carcinoma include:
 
  • Basal cell carcinoma is a disease in which malignant (cancerous) cells form in the tissues of the skin
  • Skin color and exposure to sunlight can affect the risk of developing basal cell carcinoma and actinic keratosis
  • Basal cell carcinoma often appears as a change in the skin
  • Tests or procedures that examine the skin are used to detect and diagnose basal cell carcinoma
  • Certain factors affect prognosis (chance of recovery) and treatment options for basal cell carcinoma.
Written by/reviewed by: Arthur Schoenstadt, MD
Last reviewed by: Arthur Schoenstadt, MD