How Serious Is Basal Cell Skin Cancer?

Basal cell skin cancer, also called basal cell carcinoma, is usually very curable, but it can cause disfigurement and complications if it's not treated. In the majority of cases, basal cell carcinoma is very treatable.

It is unusual for basal cell carcinoma to cause death. Approximately 2,000 people in the U.S. die each year from basal and squamous skin cancers. In most cases, people who die from these types of skin cancer tend to be older, immunosuppressed, or have been diagnosed at a very late stage. 

What Is Basal Cell Carcinoma?

Basal cell carcinoma is the most common form of skin cancer, with approximately 80% of skin cancers developing from basal cells. The epidermis (top layer of the skin) has three types of cells. The cells in the bottom layer of the epidermis are the basal cells.

Basal cells consistently divide to form new cells. These replace squamous cells, pushing old cells towards the skin's surface, where they die and slough off. Cancers that start in this bottom/basal layer of skin cells are called basal cell carcinoma.

Basal cell carcinoma is usually triggered by damage from ultraviolet (UV) radiation. This is most commonly from either exposure to the sun or tanning beds. UV radiation can damage basal cells, causing them to change and grow uncontrollably.

Types of Basal Cell Carcinoma

There are several types of basal cell carcinoma, including:

• Nodular basal cell carcinoma: Approximately 60-80% of all basal cell carcinomas that present on the face or head are nodular. It is the most common subtype, and it is also known as nodulocystic carcinoma. It presents as a shiny, smooth nodule. It may have a dip in the center, with rolled edges, and blood vessels are often seen to cross its surface.
• Superficial spreading basal cell carcinoma: Most commonly seen on the upper body, back, and shoulders, this type is more common in younger adults. It presents as shallow, scaly, irregular plaques that are pink or a similar color to the skin itself. Almost all superficial spreading basal cell carcinomas are secondary to sun damage.
• Sclerosing basal cell carcinoma (aka morphoeic basal cell or infiltrating basal cell skin cancer): This type can be challenging to diagnose. Most commonly seen on the face, it can look like a small, waxy, white scar that expands over time. It can be more dangerous or disfiguring because it is often not recognized as skin cancer until it has grown.
• Pigmented basal cell carcinoma: Most commonly occurs in people with a darker skin tone, particularly Asians. The pigmentation can be found in the different basal cell carcinoma subtypes and it can appear dark blue, dark brown, or black.

Staging Basal Cell Carcinoma

In most cases, basal cell carcinoma does not require staging because it rarely spreads. Staging is only applicable if your cancer is very large or has spread. It determines how severe the cancer is and how to treat it.

The TNM system is used most often to stage cancer:

• Tumor: Takes into consideration tumor size and if it has infiltrated into other structures nearby, such as bone. 
• Node: Describes cancer spread to the lymph nodes.
• Metastases: Identifies if cancer has spread to other distant body parts.

Staging

The stages are numbered and graded as follows:

• Stage 0: Cancer is found only in the original tumor in the skin. It is only in the epidermis and has not spread to the dermis. Stage 0 is also called Bowen's disease or carcinoma in situ.
• Stage 1: The tumor is 2 centimeters (cm) wide or smaller. It may have spread into the dermis, but not outside the skin. The tumor had no more than two high-risk features.
• Stage 2: The tumor is larger than 2 cm and may have spread from the epidermis into the dermis. It may also have high-risk features, such as perineural invasion (cancer has spread into the space around a nerve). Stage 2 tumors can also be any size with two or more high-risk features. 
• Stage 3: Cancer has spread to areas below the skin, such as into muscle, bone, cartilage, or lymph nodes, but only near the original tumor. It has not spread to distant organs.
• Stage 4: The tumor can be any size and may have spread to nearby lymph nodes. It has spread to distant organs like the brain or lungs, or has invaded the bones, or perineural invasion of the skull base.

Grading

Grading is a way to describe cancer based on its cellular appearance under a microscope.

• Grade 1:  Low grade. Most of the cells look like normal cells.
• Grade 2: The cells have features of normal cells.
• Grade 3: High grade. The cells look very abnormal.

Serious Complications

If left untreated, basal cell carcinoma can spread across the skin tissue, and in some cases, may lead to disfigurement. Although rare, it can spread and metastasize to other parts of the body, such as the bones and lungs.

Further complications of basal skin cancer include:

• Risk of recurrence
• Increased risk of developing other types of skin cancer

Can Basal Cell Carcinoma Be Cured?

In the vast majority of cases, basal cell skin cancer can be cured. The survival rates are excellent; however, the exact statistics remain unknown. Unlike other cancers, basal and squamous cell skin cancers are not tracked by cancer registries, so the statistics are not available.

In some cases, basal skin cancer can recur. The risk of recurrence appears to be linked to the type of treatment used to treat the cancer.

Research has indicated that the recurrence risk is:

• Just above 10% after surgical excision
• Slightly less than 8% after electrodesiccation and curettage
• Approximately 7.5% after cryotherapy
• Less than 1% after Mohs micrographic surgery

Treatment options vary depending on the subtype, staging, and location of the basal skin cancer.

Medications

Medications used include:

• Chemotherapy: Anti-cancer drugs either injected into a vein or given orally in the mouth
• Targeted therapy: Drugs that specifically target proteins present in the cancer cells 
• Immunotherapy: Medicines that encourage your own immune system to identify and destroy cancer cells more effectively

Local treatments

Local treatments include:

• Cryotherapy: Liquid nitrogen is used to freeze and kill the cells.
• Laser surgery: Laser light is concentrated via a beam to vaporize cancer cells.
• Photodynamic therapy: A medication is applied to the skin. Then the skin is exposed to a special light-emitting device for several minutes to a few hours.
• Chemical peeling: A chemical is applied to the skin. killing the tumor cells over several days.
• Topical chemotherapy: Anti-cancer chemotherapy medication is applied directly to the skin.
• Immune response modifiers: They are designed to boost the body's immune response against cancer. This can cause it to shrink and disappear.

Surgical Removal

Surgical methods include:

• Curettage and electrodesiccation: The basal cell carcinoma is scraped from the skin using a technique called curetting. Electrodesiccation then uses heat to destroy any remaining cancer cells.
• Mohs micrographic surgery: A very thin layer of the skin, which includes the tumor, is removed. This sample is then checked under a microscope. If cancer cells remain, another layer is removed and examined. This procedure is repeated until no more cancer cells are seen under the microscope. 
• Wide excision: The basal cell skin cancer is removed surgically along with an area of normal-looking skin around it.

Radiation Therapy

Radiation therapy for skin cancer uses high-energy rays or particles to kill cancer cells.

Prevention

You can reduce your risk of developing basal cell carcinoma by undertaking preventative measures:

• Avoid the sun during the middle of the day when it is at it's strongest
• When out in the sun, look for shade to limit your UV exposure
• Wear a broad-spectrum sunscreen all year round—remember it doesn't have to be sunny for UV rays to damage your skin
• Take extra precautions near water, snow, and sand. UV rays can reflect off these, increasing the chance of sunburn
• Wear protective clothing.
• Wear protective sunglasses.
• Avoid tanning beds.
• Ensure children are protected from the sun.
• Check your skin regularly and report changes to your doctor.

A Word From Verywell

Basal cell carcinoma can appear differently from one person to another. This is why it is important to check your skin regularly and report any changes to your doctor. Skin cancers can be treated if found early, but they can spread, cause disfigurement, or metastasize if left untreated. 

Basal cell skin cancer has excellent survival rates when it is treated early. Regularly checking your skin will help you catch changes early.

The best way to lower your risk of developing basal cell skin cancer is through prevention. Protect yourself from harmful UV rays with sunscreen, sunglasses, and clothing as much as possible.