Basal Cell Carcinoma (Skin Cancer)

Basal cell carcinoma (BCC), also called basal cell skin cancer or basal cell cancer, is the most common type of skin cancer, accounting for almost 80 percent of all non-melanoma skin cancers. They start in the basal cells, which are microscopic cells in the outer layer of your skin — the epidermis. 

BCCs usually develop on sun-exposed areas, especially the face, head, neck and arms. They tend to grow slowly. It’s very rare for a basal cell cancer to spread to other parts of the body. But if BCC is left untreated, it can grow into nearby areas and invade the bone or other tissues beneath the skin. If not removed completely, BCC can come back in the same place on the skin. People who have had basal cell skin cancers are also more likely to get new ones in other places.  

Types & Stages

There are four main clinical types of basal cell carcinoma and each vary in their appearance and characteristics. They are:

• Nodular. This is the most common type, characterized by a shiny, translucent bump, often with visible small blood vessels. The center may ulcerate as it grows, forming a rough edge appearance.  
   
• Superficial. This type appears as a flat, scaly patch, often with a slightly raised border. It can be mistaken for eczema or psoriasis. 
   
• Morpheaform (also known as sclerosing, fibrosing or morphoeic). This type is characterized by a pale, scar-like area with poorly defined edges. It’s often more difficult to detect and can be more aggressive.
   
• Pigmented. This is a rare type of BCC that causes hyperpigmentation—meaning an area of your skin becomes darker than the skin surrounding it. This type contains melanin, giving it a brown or black color. It can resemble melanoma and its appearance can vary. 

Signs & Symptoms

Basal cell cancers usually develop on areas exposed to the sun, especially the face, head, neck and arms, but they can occur anywhere on the body.

• In people with lighter-colored skin, basal cell skin cancer can appear as:
  • small, pink or red, translucent, shiny, pearly bumps, which might have blue, brown or black areas
  • pink growths with raised edges and a lower area in their center, which might contain abnormal blood vessels spreading out like the spokes of a wheel
  • flat, firm, pale or yellow areas, similar to a scar
  • raised reddish patches that might be itchy
  • open sores (which may have oozing or crusted areas) that don’t heal or that heal and then come back
     
• They’re less common in people with darker skin color. When they do occur, they often have many of the same features (such as being translucent or shiny or having raised edges), although they’re often darker in color.
   
• Basal cell cancers are often fragile and might bleed after shaving or after a minor injury. If you have a sore or cut that is taking longer than a week or so to heal, check with your doctor.
   
• They can also develop as a flat area showing only slight changes from normal skin.

These and other types of skin cancers can also look different from the descriptions above. This is why it’s important to have a doctor check any new or changing skin growths.

Diagnosis

With skin self-exams and skin checks by a doctor — including a dermatologist — basal cell skin cancers can often be found early, making them easier to treat. Be sure to show your doctor any areas that concern you and ask them to look at areas that may be hard for you to see, like on your back.  

If you have signs or symptoms of basal cell carcinoma, your doctor will examine you and ask you questions about your health, your lifestyle and your family history. If your doctor suspects a spot may be BCC, a biopsy will be done. Your doctor may use one of these methods:

• Local excision/excisional biopsy. The entire suspicious area is removed with a scalpel under local anesthetic. Depending on the size and location of the suspicious area, this type of biopsy may be done in a doctor's office or as an outpatient procedure at a hospital. Your doctor will put in stitches to close the excision and cover the area with a bandage.
   
• Punch biopsy. For this, a tool that looks like a tiny round cookie cutter is used to remove a deeper sample of skin. Your doctor rotates the punch biopsy tool on the skin until it cuts through all the layers. The sample is then removed, and the edges of the biopsy site are stitched together.
   
• Shave biopsy. This biopsy procedure, also known as saucerization, shaves off the top layers of the skin with a small surgical blade. Any bleeding is then stopped by putting either an ointment or a chemical that stops bleeding on it, or by using a small electrical current to seal (cauterize) the wound.

The sample of skin is sent to a pathologist, who looks at it under a microscope to check for cancer cells. 

Treatment    

There are several types of treatment used to remove or destroy basal cell skin cancers. The options depend on factors such as the tumor size and location, and your age, general health and preferences. These cancers very rarely spread to other parts of the body, although they can still grow into nearby tissues and cause serious problems if not treated. Options include: 

• Surgery. If the tumor hasn’t already been removed in the biopsy procedure, other options are: 
   
  • Curettage and electrodesiccation: This is a common treatment for small BCCs that are at low risk for coming back after treatment. It might need to be repeated to help make sure all of the cancer has been removed.
     
  • Shave excision: Shaving off the top layers of the skin (including the tumor) with a small surgical blade might be another option for small BCCs that are at low risk for coming back after treatment.
     
  • Standard excision: This type of surgery, in which the tumor and a margin of normal skin around it are removed, is a common treatment for low-risk BCCs. It might also be an option for some BCCs at higher risk for coming back, especially if they’re on your trunk (chest or back), arms or legs.
     
  • Mohs surgery. Also known as Mohs micrographic surgery or MMS, it’s especially useful for treating BCCs that are at higher risk for coming back. This type of surgery is done by a specially trained dermatologist or surgeon. In this procedure, the skin (including the BCC) is removed in very thin layers. Each layer is quickly frozen and looked at with a microscope. If cancer cells are seen, the doctor removes another layer of skin. This is repeated until a layer shows no signs of cancer. This is a slow process, often taking several hours, but it means that more normal skin near the tumor can be saved, which can help the area look better after surgery.
     
• Radiation therapy. It’s often a good option for treating people who aren’t able (or don’t want) to have surgery, as well as for treating tumors on the eyelids, nose or ears, which can be hard to treat surgically. Radiation might also be a good option for some older people if curing the cancer may not be as important as controlling it over the long term (and limiting side effects). Radiation is also sometimes used after surgery if it’s not clear that all of the cancer has been removed, or if there’s a higher risk that the cancer might come back.
   
• Other local and topical treatments. These are sometimes options for treating superficial BCCs (tumors that haven’t grown too deeply into the skin) and include:
   
  • Freezing (cryotherapy). They can be removed by freezing them with liquid nitrogen. Your health care provider applies the substance to the affected skin, which causes blistering or peeling. As your skin heals, the damaged cells slough off, allowing new skin to appear. It takes only a few minutes and can be done in your doctor’s office. 
     
  • Photodynamic therapy. Your doctor might apply a light-sensitive chemical solution to the affected skin and then expose it to a special light that will destroy the BCC. 
     
  • Topical chemotherapy. This is an anti-cancer medicine that is put directly on the skin (usually in a cream or ointment) rather than being taken by mouth or given as an IV into a vein. Because the drug is only applied to the skin, it doesn’t spread throughout the body, so it doesn’t cause the same side effects as the other types of  chemotherapy. 
     
  • Immune response modifiers. Some topical creams can boost the body’s immune response against some very early basal cell cancers, causing them to shrink and go away. 
     
• Targeted therapy or immunotherapy for advanced basal cell cancers. This is an option in rare cases where basal cell cancer spreads to other parts of the body or can’t be cured with surgery or radiation therapy. It can often shrink or slow its growth.

Causes & Risk Factors

Several risk factors make a person more likely to get basal cell skin cancer. These include: 

• Exposure to ultraviolet (UV) light. This includes sunlight, tanning beds and sun lamps.
   
• Having light-colored skin. Anyone can get skin cancer, but people with light-colored skin have a much higher risk than people with naturally darker skin color. White people with fair (light-colored) skin that freckles or burns easily, blue or green eyes, and naturally red or blonde hair are at especially high risk.
   
• Albinism. This is an inherited lack of protective skin pigment. People with this condition may have pink-white skin and white hair. They have a very high risk of getting sunburns and skin cancer, so they need to be extra careful to protect their skin.
   
• Age. The risk increases as people age likely because of the buildup of sun exposure over time. But these cancers are becoming more common in younger people as well probably for the same reason.
   
• Gender. Men are more likely than women to get basal cell cancers of the skin. This is thought to be due mainly to getting more sun exposure.
   
• Exposure to certain chemicals. This includes large amounts of arsenic—an element found naturally in well water in some areas and used in making some pesticides and in some other industries. Workers exposed to coal tar, paraffin and certain types of petroleum products may also have an increased risk of skin cancer.
   
• Radiation exposure. People who have had radiation treatment have a higher risk of developing skin cancer in the area where the radiation was focused. This is particularly a concern in children who have had radiation treatment for cancer.
   
• Previous skin cancer. People who have had a basal or squamous cell cancer have a much higher chance of developing another one.
   
• Long-term or severe skin inflammation or injury. Scars from severe burns, areas of skin over serious bone infections, and skin damaged by some severe inflammatory skin diseases are more likely to develop skin cancers (mostly squamous cell cancers), although this risk is generally small.
   
• Xeroderma pigmentosum (XP). This very rare inherited condition reduces the ability of skin cells to repair DNA damage caused by sun exposure. People with this disorder often develop many skin cancers, starting in childhood.
   
• Basal cell nevus syndrome (also known as nevoid basal cell carcinoma syndrome or Gorlin syndrome). In this rare congenital (present at birth) condition, people develop many basal cell cancers over their lifetime. People with this syndrome may also have abnormalities of the jaw (and other bones), eyes and nervous tissue.  Most often basal cell nevus syndrome is inherited from a parent. In families with this syndrome, those affected often start to develop basal cell cancers as children or teens. Exposure to UV rays can increase the number of tumors these people get.
   
• Other genetic syndromes. These have also been linked with an increased risk of skin cancer:
  • Epidermolysis bullosa
  • Fanconi anemia
  • Muir-Torre syndrome
  • Rothmund-Thomson syndrome
  • Bloom syndrome
  • Werner syndrome
     
• A weakened immune system. This can occur from certain diseases or medical treatments, including in people infected with HIV, the virus that causes AIDS. 

Screening

With skin self-exams and skin checks by a health care professional like a dermatologist, basal cell skin cancers can often be found early. When skin cancers are found early, they are likely to be easier to treat.