BASAL CELL CARCINOMA

Basal cell carcinoma (BCC) is the most common type of skin cancer in the United States. It accounts for approximately 80% of all skin cancers. It usually occurs on sun exposed areas such as head and neck region and upper trunk. It is slow growing and rarely spreads to internal organs, but can cause local tissue destruction.

Risk factors for BCC

• Ultraviolet (UV) radiation
  BCC typically affects fair-skinned Caucasians who have had a lot of sun exposure.  Repeated sun exposure to the basal cells (skin cells that form the lowest layer of the epidermis) causes them to become cancerous.  It may take 20 to 50 years from the time of UV damage to development of BCC.
• Approximately two-thirds of BCCs arise in sun-exposed areas of the body:  face, ears, scalp, neck, and upper trunk.  One-third of BCCs occur in non-sun exposed areas suggesting a genetic susceptibility.
  
• Other radiation: 
  X-ray and grenz-ray exposure.
  
• Chemicals:
  Chronic arsenic exposure, industrial coal tar and paraffin.
  
• Immunosuppression: 
  History of immunosuppression such as HIV, blood cancers (lymphomas), organ transplant or chronic immunosuppressive medications.
• Genetic predisposition: 
  Rare inherited disorders such as Xeroderma pigmentosum or Basal cell nevus syndrome.

Diagnosis of BCC:
BCC often presents as a non-healing bleeding sore, translucent firm papule, waxy scar or pink scaly patch. Most nodular BCCs can be diagnosed clinically.  However, a skin biopsy under local anesthetic can be performed and examined under a microscope for cancerous cells for confirmation.
 

Treatments of BCCs:
There is no one best method to treat all skin cancers.  The treatment for BCC depends on various factors:

• The type, size, location, and number of lesions to be treated.
  
• Whether it is primary or recurrent lesion.
  
• The health condition and preferences of the patient.

The end result is usually excellent for most of methods of treatment, with cure rate of 75% to 99%. 

Treatment options:

• Cryosurgery
  Destroy the cancerous cells with liquid nitrogen.
  
• Electrodessication and curettage
  Removes the skin cancer and some surrounding skin by scraping with a curette and the base is cauterized with an electric needle.
  
• Simple surgical excision
  The BCC is cut out (excised) with some healthy surrounding skin.  The wound is closed with stitches and the excised skin is examined under a microscope to verify clear margins (all cancer cells are removed).
  
• Mohs Micrographic surgery
  A special technique where the skin is microscopically examined in layers as it is removed.  This minimizes recurrence and the amount of healthy tissue that needs to be removed.  It is indicated mainly for lesions that are large, scar-like (morpheaform), have recurred after previously being treated, and are in cosmetically sensitive areas (T zone of the face, and ears).
  
• Radiation therapy
  X-rays or electron beam radiation damages cancer cells of large BCCs that cannot be removed surgically, or for elderly or debilitated patients who cannot tolerate surgery.
  
• Chemotherapy/Immune modulators
  Topical medications such as 5-fluorouracil (5-FU) and imiquimod applied to skin cancer as home treatment.
   

Prevention of BCC:
Sun protection with clothing, hats, and sunscreen is the best way to prevent development of skin cancers.  Have a complete skin examination periodically by your physician.  Examine your own skin every month and bring any new or unusual growths to the attention of your doctor.  BCCs that are detected early are easier to treat and result in less scarring.
 

References:
1.  www.aad.org
2.  www.skincancerfoundation.org