What Is Basal Cell Carcinoma?

Basal cell carcinoma—also known as basal cell skin cancer—is the most common type of skin cancer in the U.S. Basal cell carcinoma begins in the basal cells of your skin. The most common cause of this condition is basal cell damage from exposure to ultraviolet (UV) light from the sun or tanning beds. 

The most common symptoms of basal cell carcinoma include a small sore or lesion that does not heal or a patch of scaly skin. Fortunately, when diagnosed in an early stage, basal cell carcinoma is very treatable. Your primary care provider and a dermatologist (or, a doctor who specializes in skin disorders) will likely work together to find the treatment options that are right for you.

Types of Skin Cancer

Basal cell carcinoma is the most common type of skin cancer among people living in the U.S. Other types of skin cancer include:

• Squamous cell carcinoma: The second most common type of skin cancer in the U.S. Like basal cell carcinoma, this type of cancer also causes a sore on your skin that looks like it won’t heal.
• Melanoma: A more serious type of skin cancer that appears as a dark brown or black mole.
• Merkel cell carcinoma: A rare type of skin cancer that appears as a bluish-red nodule on the skin.

Symptoms

Basal cell carcinoma lesions or sores usually develop on the areas of the skin that receive the most sunlight. This often includes the face, neck, scalp, and ears. If you notice a sore develop on your skin, it's important to look for the following signs:

• Open sore: A sore that does not heal over time or a lesion that oozes or begins to look crusty
• Scar-like growth: A flat, firm sore that looks like a scar that is typically yellow or flesh-colored
• Red patch: An area of the skin that feels itchy and looks raised and reddish in color
• Pearly bump: A small, shiny bump that is pink or red in color and has specks of blue and black coloring
• Growth with raised edges: A pink growth that is lower in the middle and raised around the edges
• Bleeding: A lesion that feels sensitive and may bleed easily

Causes

When the DNA in your basal cells in the skin becomes damaged, basal cell carcinoma can occur. DNA is the material in your cells that stores your genetic information. When there is damage to your DNA, your cells no longer grow and reproduce at a normal rate. 

Cells that have DNA damage may start to grow at an out-of-control rate, which can lead to cancer. The most common cause of skin cell damage is ultraviolet (UV) rays from the sun or a tanning bed. 

Risk Factors

The most significant risk factor for basal cell carcinoma is time spent in the sun. A 2014 study found that an estimated 90% of non-melanoma skin cancers are directly caused by sun exposure. 

You may also be at an increased risk of basal skin carcinoma if you:

• Have a personal or family history of skin cancer
• Were assigned male at birth
• Use tanning beds
• Are over the age of 50
• Experience chronic skin infections
• Live with an autoimmune disorder
  

Diagnosis

Basal cell carcinoma is a common type of cancer and most dermatologists are experts at recognizing the condition. If you are concerned about a sore that will not heal or any other abnormal area of the skin, it's important to see your healthcare provider or your dermatologist right away. They will likely start your appointment by performing a physical exam and asking about your medical history. 

If your dermatologist suspects skin cancer, they will typically recommend testing a sample of skin tissue with a biopsy—a common procedure that providers use to detect cancer. The most common types of biopsies providers use to diagnose skin cancer include:

• Shave biopsy: Shaves off the top layers of skin using a surgical blade
• Punch biopsy: Uses a round, metal tool to remove deeper layers of skin
• Excisional biopsy: Surgically extracts the entire tumor (for larger areas of concern)
• Incisional biopsy: Takes out part of the tumor
• Lymph node biopsy: Removes a sample of tissue from your lesion's nearest lymph node to determine if cancer cells have spread to other areas of the body

Once your healthcare provider obtains a sample of your tissue for a biopsy, they will send it to the lab where a pathologist (a specialist who examines bodies and body tissue) examines the sample under a microscope to check for cancer cells. 

Stages of Basal Cell Carcinoma 

Basal cell carcinoma is considered a slow-growing cancer. Dermatologists are usually able to diagnose it in an early stage before the cancer has spread to other areas of the body. 

To determine the stage of basal cell carcinoma, your healthcare team will use the TNM system:

• Tumor: Measures the size of the tumor and determines if it has grown deeper into the skin
• Node: Notes if cancer cells have spread to the lymph nodes 
• Metastasis: Determines if cancer has spread (metastasized) to other areas of the body
  

Treatment

The goal of basal cell carcinoma treatment is to cure the cancer. This involves removing the cancerous area from the skin and preventing it from coming back. 

A common treatment for basal cell carcinoma is surgery. A Mohs surgeon is a medical doctor who specializes in treating cancer with surgery. This type of provider may perform one of the following surgeries depending on your exact case of basal cell carcinoma:

• Excision: The surgeon removes the tumor and surrounding healthy skin with a surgical blade.
• Curettage and electrodesiccation: The dermatologist or surgeon uses a tool to scrape away cancer cells and then burns the skin to stop bleeding and prevent infection.
• MOHS surgery: The provider removes thin layers of your skin and examines them under a microscope until no cancer cells are visible. This type of surgery has the lowest recurrence rate. This means that it is the most effective at preventing cancer in the future. 
  

Rarely, basal cell carcinoma may spread to other areas of the body. If this happens, your healthcare team will discuss further treatment options with you. These options may include radiation therapy, immunotherapy, or chemotherapy.

How to Prevent Basal Cell Carcinoma 

Fortunately, many cases of basal cell carcinoma are preventable. To protect yourself against basal cell carcinoma, take precautions when spending time in the sun. The UV rays from the sun or tanning beds are responsible for the majority of basal cell carcinoma cases in the United States. 

To protect your skin from UV rays, take the following precautions:

• Take frequent breaks or sit in the shade when spending time outdoors
• Apply sunscreen with a high sun protective factor (SPF) before going outdoors, even in the winter
• Wear skin-protective clothing like a hat, sunglasses, and a long-sleeved shirt
• Refrain from using tanning beds

If you have a personal or family medical history of skin cancer, it's also a good idea to see your healthcare provider annually for a skin exam and screening.

Related Conditions 

Most cases of basal cell carcinoma are curable. However, once you have had basal cell carcinoma, your risk for other types of skin cancer increases. You are at higher risk of developing basal cell carcinoma again, squamous cell carcinoma, and melanoma in the future. For this reason, see your dermatologist regularly for skin checks.

Living With Basal Cell Carcinoma

Most people who develop basal cell carcinoma receive an early diagnosis and treatment. Because your risk of getting cancer increases if you've already had cancer, it’s still important to see your dermatologist regularly after you finish treatment or if your skin cancer has been cured. It's worth noting that while this condition is curable, incorporating prevention strategies for the future can reduce your risk of your cancer returning.