Although basal cell carcinoma is very common, the disease is highly curable. However, it may be fatal in patients, particularly elderly people, who fail to receive treatment in the early stages. People with suppressed immune systems are also at an increased risk of dying from the disease. 

According to the Centers for Disease Control and Prevention (CDC), approximately 95 percent of basal cell carcinomas can be cured when discovered in the early stages. Early detection is also important because left untreated the disease can cause severe damage and disfigurement.

The choice of therapy depends on the location, size and type of tumor, as well as the patient. Although the cure rate is excellent, different therapies have different rates of cancer return.

Common methods used in the treatment of basal cell carcinoma include:

• Electrodesiccation and curettage. This procedure involves anesthetizing the area and scraping the cancer with a curettage, a long thin instrument with a sharp edge. Once the tumor is removed, the area is treated with an electric needle to destroy any remaining cancer cells. This treatment method is commonly used to treat smaller basal cell carcinomas, measuring less than 5 millimeters (slightly less than 1/4 inch).
  
  
• Simple excision. This procedure involves removing the tumor while under local anesthesia with a surgical knife, along with a section of normal skin surrounding the tumor. The remaining skin is then stitched together. Lesions in delicate areas, such as the eyelid or lip require plastic surgery by a trained ophthalmologist or plastic surgeon.
  
  
• Mohs surgery. This procedure involves surgically "shaving" the layers of skin that the cancer may have invaded. The skin samples are then examined under a microscope. If the sample is malignant (cancerous), more sections of the tumor are removed and examined under a microscope. This process continues until a cancer-free skin sample is found, resulting in a ‘clean margin.’ This treatment method is useful in treating large, high-risk tumors or tumors on or near the eyes, ears, nose, scalp, forehead, fingers and genital area.
  
  
• Radiation therapy. This treatment method uses high-energy rays to destroy cancer cells and shrink tumors. It is useful in treating older patients with large tumors and tumors involving areas that are difficult to treat surgically (e.g., eyelids, nose, ears).
  
  
• Laser surgery. This procedure uses a focused laser beam to make cuts in tissue or to vaporize (burn off) cancer cells. It is sometimes used to treat very superficial tumors (tumors that have not extended too deeply under the surface of the skin). Because it does not destroy cancer cells that are located deep under the skin surface, the treatment requires close monitoring by the patient and dermatologist (a physician specializing in diseases of the skin).
  
  
• Cryosurgery. This procedure uses liquid nitrogen to freeze and destroy cancer cells. It is used to treat some small basal cell carcinomas, but is not typically used to treat large tumors or those located in certain areas of the nose, ears, eyelids, scalp or legs.
  
  
• Topical chemotherapy. Chemotherapy uses powerful drugs to destroy cancer cells. When used to treat basal cell carcinoma, chemotherapy is usually topical (applied to the skin in the form of a cream or lotion). Topical chemotherapy is often able to destroy cancer cells located near the skin surface, but unable to reach cancer cells that are located deep in the skin. This treatment is not used to treat cancer that has spread to other organs. The most common topical medication is 5-fluorouracil.
  
  
• Biological therapy. Also known as immunotherapy, biological therapy uses a patient’s immune system to destroy cancer cells. Substances normally found in the body are created in a laboratory and used to increase, direct or restore the body’s natural defense against the disease. In some forms of biological therapy, the substances are used to directly attack the cancer cells.
  
  One such biological agent used to treat some basal cell carcinomas is imiquimod. Used daily for several weeks, the drug comes in the form of a cream. When applied topically to the skin, imiquimod causes the body to react to the growth and triggers its destruction. Clinical trials of interferon have shown some success, but the treatment is more expensive and may produce troublesome side effects.
  
  
• Photodynamic therapy (PDT). This treatment method uses a drug and a specific type of laser to destroy cancer cells. A drug that is not active until it is exposed to light is injected into the patient’s vein. The drug then accumulates in the cancer cells than in the normal cells. Fiberoptic tubes are then used to deliver laser light to the cancer cells. After the drug is exposed to the light, it becomes active and destroys the cancer cells, while causing little damage to healthy tissue. The exact role of PDT in treating skin cancers continues to be studied by researchers.

Scientists continue to study a number of areas to further understand the causes, prevention and treatment of skin cancer. Clinical studies are examining the association of ultraviolet light and DNA changes that can result in skin cells becoming cancerous. Researchers are using this information to continually work toward the development of new treatment strategies for the disease.

Follow-up examinations are very important for basal cell carcinoma patients because the cancer can recur (come back). The recurrence may appear in the same place on the skin or new basal cell carcinomas can develop in another area of skin. According to the American Cancer Society (ACS), 35 to 50 percent of patients diagnosed with one basal cell carcinoma develop a new skin cancer within five years of the first diagnosis.

The ACS states that approximately 5 percent of basal cell carcinomas measuring less than 5 millimeters (slightly less than 1/4 inch) will return after treatment with electrodesiccation and curettage.  Approximately half of the tumors larger than 3 centimeters (slightly less than 1-1/4 inch) will recur within five years of the procedure.

Among patients treated with simple excision, the recurrence rate for tumors less than 1.5 centimeters (slightly less than 3/4 inch) is approximately 12 percent. For tumors measuring more than 3 centimeters (slightly less than 1 1/4 inch) the rate is about 23 percent.

Following treatment, the ACS recommends that patients have a skin examination every six months for five years, and then annually. Although the disease may recur, the cure rates for recurrent basal cell carcinoma are quite good. According to the ACS, the cure rate for basal cell carcinomas that have returned after treatment is approximately 96 percent when Mohs surgery is used, and approximately 50 percent for most other methods of treatment.