Nonmelanoma Skin Cancer: Introduction

What is cancer?

Cancer is when cells in the body change and grow out of control. To help you understand what happens when you have cancer, let’s look at how your body works normally. Your body is made up of tiny building blocks called cells. Normal cells grow when your body needs them, and die when your body does not need them any longer.

Cancer is made up of abnormal cells that grow even though your body doesn’t need them. In most cancers, the abnormal cells grow to form a lump or mass called a tumor. If cancer cells are in the body long enough, they can grow into (invade) nearby areas. They can even spread to other parts of the body (metastasis).

What is nonmelanoma skin cancer?

Skin cancer is a disease that begins in the cells of the skin. The area of skin with the cancer is often called a lesion. There are several types of skin cancer (carcinoma). Melanoma is the most serious. But there are others that are known as nonmelanoma skin cancer. These include:

  • Basal cell carcinoma

  • Squamous cell carcinoma

  • Merkel cell carcinoma

  • Cutaneous T-cell lymphoma

  • Kaposi sarcoma

Basal cell carcinoma and squamous cell carcinoma are by far the most common.

Understanding the skin

Anatomy of the skin

The skin is the largest organ of the body. Skin protects us from heat, sunlight, injury, and infection. It also stores water and fat, and makes vitamin D. The skin has 3 layers:

  • The outer layer called the epidermis

  • The middle layer called the dermis

  • The inner layer called the subcutis (subcutaneous)

The epidermis is made of flat cells called squamous cells. Round basal cells are under the squamous cells. The lower part of the epidermis has pigment-producing cells called melanocytes. These cells darken the skin when exposed to the sun.

The dermis has blood vessels, lymphatic vessels, hair follicles, and glands. Some of these glands make sweat, which helps keep the body cool. Other glands make an oily substance called sebum. Sebum helps keep the skin from getting dry. Sweat and sebum reach the skin's surface through tiny openings called pores.

The subcutis and the lowest part of the dermis form a network of collagen and fat cells. This layer conserves heat and helps protect the body's organs from injury.

What are the different types of nonmelanoma skin cancer?

Basal cell carcinoma

Basal cell carcinoma, also known as basal cell cancer, is the most common type of skin cancer. It begins in basal cells in the deepest part of the epidermis. It often starts in areas of skin exposed to the sun, such as the face, head, neck, arms, and hands. The cancer lesion often appears as small, raised, shiny, or pearly bumps, but it can have various kinds of appearance. They tend to grow slowly and rarely spread to other parts of the body.

Nearly all basal cell cancers can be treated and cured. In some cases they may come back after treatment. Although this type of cancer rarely spreads to other parts of the body, if not treated it can extend below the skin to the bone. This can cause serious damage to the bone. Having a basal cell carcinoma also puts you at higher risk for other types of skin cancer.

Basal cell carcinoma forms in places exposed to the sun. A lesion often looks raised, shiny, or pearly.

Squamous cell carcinoma

Squamous cell carcinoma, also known as squamous cell cancer, is the second most common type of skin cancer. It begins in flat cells called squamous cells in the upper part of the epidermis. Like basal cell cancer, it often starts in areas of skin exposed to the sun, such as the face, head, neck, arms, and hands. But it can also start in other parts of the body, such as skin in the genital area. Squamous cell carcinoma lesions often appear as a rough or scaly reddish patch on the skin that tends to grow quickly. But it can also have various kinds of appearance.

Squamous cell carcinoma is more likely to grow and spread to other parts of the body than basal cell carcinoma, although this is still uncommon. Most squamous cell carcinoma is found early enough to be treated and cured.

Squamous cell carcinoma can form in places exposed to the sun. A lesion often looks like a rough or scaly reddish patch.

Merkel cell carcinoma

Merkel cell cancer is a rare type of skin cancer. Merkel cells are types of cells in the upper layer of the skin. The cells are very close to nerve endings, and help the skin sense light touch. Merkel cell cancer occurs when these cells grow out of control. Merkel cell cancer can be dangerous because it tends to grow quickly. It can be hard to treat if it spreads beyond the skin.

Merkel cell cancer tumors are most often found on sun-exposed areas of skin, such as the face, neck, and arms. But they can start anywhere on the body. They usually appear as firm, shiny skin lumps that do not hurt. The lumps may be red, pink, or blue. They tend to grow very quickly.

Cutaneous T-cell lymphoma

Cutaneous T-cell lymphoma is a type of cancer that starts in blood cells called T-lymphocytes. These are white blood cells that are part of your immune system. They normally fight infection in the body. The cancer then affects the skin (cutaneous). It causes scaly patches or bumps. The cancer is also known as lymphoma of the skin. It is a type of non-Hodgkin lymphoma.

It is usually a slow-growing cancer. It develops over many years. The two most common types of this cancer are mycosis fungoides and the Sezary syndrome.

Talk with your healthcare provider

If you have questions about nonmelanoma skin cancer, talk with your healthcare provider. Your healthcare provider can help you understand more about this cancer.

Risk Factors

Nonmelanoma Skin Cancer: Risk Factors

What is a risk factor?

A risk factor is anything that may increase your chance of having a disease. Risk factors for a certain type of cancer might include smoking, diet, family history, or many other things. The exact cause of someone’s cancer may not be known. But risk factors can make it more likely for a person to have cancer.

Things you should know about risk factors for cancer:

  • Risk factors can increase a person's risk, but they do not necessarily cause the disease. 

  • Some people with 1 or more risk factors never develop cancer. Other people can develop cancer and have no risk factors.

  • Some risk factors are very well known. But there is ongoing research about risk factors for many types of cancer.

Some risk factors, such as family history, may not be in your control. But others might be things you can change. Knowing the risk factors can help you make choices that might lower your risk. For example, sun exposure is a risk factor  for many types of skin cancer, and you can protect yourself from the sun.

Who is at risk for nonmelanoma skin cancer?

The most common risk factors for nonmelanoma skin cancer include:

  • Sun exposure. The sun's ultraviolet (UV) rays can damage your skin and lead to skin cancer. The more time you spend in the sun, the greater your chances are of getting skin cancer. This risk is even higher for people who live closer to the equator or who live at higher altitudes, where the sun's rays are stronger.

  • Use of tanning booths and sunlamps. These artificial sources of UV rays can also damage the skin, and the risk of cancer is especially high if they are used before age 30.

  • Certain colors of skin, hair, and eyes. People with pale skin, red or blond hair, and green, blue, or gray eyes have an increased risk of skin cancer. Having many freckles also increases your risk. But even people with darker skin can get skin cancer.

  • Personal history of skin cancer or pre-cancer. People who have had skin cancer before are at increased risk of getting it in the future. The same is true of people who have had skin pre-cancer, such as actinic keratosis.

  • Older age. While skin cancer can occur at any age, the risk rises as people get older.

  • Being male. Men are more likely to get nonmelanoma skin cancers than women.

  • Weakened immune system. People who have a weakened immune system, such as people who have had an organ transplant, are at higher risk of skin cancer. Their skin cancer is also more likely to be serious.

  • Exposure to arsenic. People who have been exposed to large amounts of arsenic have an increased risk of skin cancer.

  • Prior radiation treatment. People who have been treated with radiation therapy have a higher risk of skin cancer in the area that was treated.

  • Scars, burns, or inflamed skin. Skin cancers are more likely to develop in areas of damaged skin.

  • Smoking. People who smoke are more likely to get skin cancer, especially on the lips.

  •  Human papillomavirus (HPV) infection. Certain types of HPV can infect the skin in the genital area and increase the risk of skin cancer there.

  • Certain rare inherited conditions. People with a condition such as basal cell nevus syndrome (Gorlin syndrome) or xeroderma pigmentosum (XP) have a much higher risk of skin cancer, starting at an early age. 

What are your risk factors?

Talk with your healthcare provider about your risk factors for skin cancer. He or she may advise you to have frequent skin exams. You may also need to do monthly skin exams for yourself at home. There are also things you can do that might lower your risk for skin cancer, such as protecting yourself from the sun and not using tanning beds. Talk with your healthcare provider about the best ways to reduce your risks.


Nonmelanoma Skin Cancer: Symptoms

What are the symptoms of nonmelanoma skin cancer?

Nonmelanoma skin cancer may appear as a new growth. Or it may occur as a change in the size or in the color of a growth you already have. These changes can happen slowly or quickly. Here are things to look out for.

Basal cell carcinoma 

This type of skin cancer often develops in areas exposed to the sun, such as the head, face, neck, arms, and hands. The cancer may be:

  • A small, raised bump that is shiny or pearly. It may have small blood vessels in it.

  • A small, flat spot that is scaly, irregularly shaped, and pale, pink, or red.

  • A spot that bleeds easily and briefly, then heals up and appears to go away. It then bleeds again in a few weeks.

  • Sores that don't heal.

  • A growth with raised edges, a lower area in the center, and brown, blue, or black areas.

Squamous cell carcinoma 

Like basal cell cancer, it often starts in areas of skin exposed to the sun, such as the face, head, neck, arms, and hands. But it can also start in other parts of the body, such as skin in the genital area. The cancer may be:

  • A rough or scaly bump that appears, then grows quickly.

  • A wart-like growth that might bleed or crust over.

  • Flat, red patches on the skin that are irregularly shaped. The patches may or may not bleed.

Although these are symptoms of skin cancer, they may also be caused by other less serious problems. If you have any of these symptoms, see your doctor.

Merkel cell carcinoma

Merkel cell cancer tumors are most often found on sun-exposed areas of skin, such as the face, neck, and arms. But they can start anywhere on the body. They usually appear as firm, shiny skin lumps that do not hurt. The lumps may be red, pink, or blue. They tend to grow very quickly.

Cutaneous T-cell lymphoma

This type of skin cancer causes scaly patches or bumps. The patches or bumps are often red or purple and often itch. Here are examples of some skin cancer lesions.


When to see your healthcare provider

Many of these symptoms may be caused by other health problems. But it is important to see your healthcare provider if you have these symptoms. Only a healthcare provider can tell if you have cancer.

Newly Diagnosed

Nonmelanoma Skin Cancer: Newly Diagnosed

Being told you have skin cancer can be scary, and you may have many questions. But you have people on your healthcare team to help.           

Coping with fear

It’s normal to feel afraid. Learning about your cancer and about the treatment options you have can make you feel less afraid. This also helps you work with your healthcare team and make the best choices for your treatment. You can also ask to speak with a counselor.                                                                                                                         

Working with your healthcare team

Most nonmelanoma skin cancer can be treated by a dermatologist. This is a doctor who specializes in treating disease of the skin. If your cancer is more advanced, you may also have other types of doctors on your team. These may include:

  • Surgeon. This is a doctor with special training in surgery to treat cancer.

  • Medical oncologist. This is a healthcare provider with special training to treat cancer with medicines.

  • Radiation oncologist. This is a healthcare provider with special training to treat cancer with radiation.

  • Oncology nurse. This is a registered nurse with special training to take care of people with cancer.

They will answer any questions you may have. They’ll help you through each of the steps you’ll take before, during, and after treatment. Your team will let you know what tests you need and the results of those tests. They’ll guide you in making treatment decisions and help prepare you and your loved ones for what’s ahead.

Learning about treatment options

To decide the best course of treatment for you, your healthcare team needs to know as much as they can about your cancer. This may involve getting some tests and working with more than one doctor or other type of healthcare professional. And you may decide that you want to get a second opinion to help you choose a treatment.

Getting support

Coping with cancer can be stressful. You can talk with your healthcare team about seeing a counselor. They can refer you to someone who can help. You can also visit support groups to talk with other people coping with cancer. Ask your healthcare team about local support groups.


Nonmelanoma Skin Cancer: Stages

The stage of a cancer is how much and how far the cancer has spread in your body. Your healthcare provider uses exams and tests to find out the size of the cancer and where it is. He or she can also see if the cancer has spread to nearby areas, and if it has spread to other parts of your body. The stage of a cancer is one of the most important things to know when deciding how to treat the cancer.

In most cases, nonmelanoma skin cancer is confined to the skin and is easily treated and cured.

What are the stages of nonmelanoma skin cancer?

The stage is based on the type of nonmelanoma skin cancer (basal or squamous cell), the size of the tumor, how deeply into your skin it has grown, and if the cancer has spread beyond the tumor to other parts of your body.

If you have basal cell carcinoma, stage is seldom needed because these cancers tend to be treated and cured before they have a chance to spread.

If you have squamous cell carcinoma, your doctor may check the lymph nodes near the tumor to see if the cancer has spread to them.

Skin cancer staging is very complex. The TNM system from the American Joint Commission on Cancer (AJCC) is most often used to stage squamous (and sometimes basal) cell skin cancers of the head and neck. Be sure to ask your healthcare provider to explain the stage of your cancer to you in a way you can understand.

The first step in staging is to find the value for each part of the TNM system. Here's what the letters stand for in the TNM system:

  • T tells how far the main tumor has spread into the skin.

  • N tells if the lymph nodes in the area of the original tumor have cancer in them.

  • M tells if the cancer has spread (metastasized) to distant organs in the body.

Numbers or letters after T, N, and M provide more details about each of these factors.

Stage groupings are determined by combining the T, N, and M values from the TNM system. These groupings give an overall description of your cancer. A stage grouping is listed as 0 or as a Roman numeral with a value of I through IV (1 through 4).  Stage 0 is also called carcinoma in situ and is the earliest stage. The higher the number, the more advanced the cancer is. Letters and numbers can be used after the Roman numeral to give more details.

Most nonmelanoma skin cancers are Stage 0 or Stage I. Stage III and IV are fairly rare.

High-risk features for nonmelanoma skin cancer

High-risk features are aspects that can make a skin cancer harder to treat. These features include:

  • The tumor is thicker than 2 millimeters.

  • The tumor has spread into the lower layer of your skin (the dermis), or into the connective tissue or fat under the dermis, called the subcutis.

  • The tumor has grown and spread along nerve pathways.

  • The tumor began on an ear or on a part of the lip that has hair on it.

  • The cancer cells look very abnormal under a microscope.

Talking with your healthcare provider

When your cancer is staged, talk with your healthcare provider about what the stage means for you. Make sure to ask questions and talk about your concerns.

Treatment Choices

Nonmelanoma Skin Cancer: Treatment Choices

There are various treatment choices for skin cancer. Which one may work best for you? It depends on a number of things. These include how large the skin cancer is, where it is, and what stage it is. Other things that affect your treatment choices include your age, health, your preferences, and what side effects you’ll find acceptable.

Learning about your treatment options

You may have questions and concerns about your treatment options. You may also want to know how you’ll feel and function during and after treatment, and if you’ll have to change your normal activities.

Your doctor is the best person to answer your questions. He or she can tell you what your treatment choices are, how successful they’re expected to be, and what the risks and side effects are. Your doctor may advise a specific treatment. Or he or she may offer more than one, and ask you to decide which one you’d like to use.

You may have just one treatment, or a combination of treatments.

Types of treatment for nonmelanoma skin cancer


Surgery is a common treatment for nonmelanoma skin cancer. It is used in most cases when the cancer is still at an early stage. Many skin cancers can be removed easily and need only very minor surgery. Others may need a more extensive surgery. The surgery choices include:

  • Simple excision. This is done to cut the cancer from the skin, along with some of the healthy tissue around it.

  • Curettage and electrodesiccation. The surgeon cuts the tumor from the skin using a sharp, spoon-shaped instrument called a curette. Then he or she uses a needle-shaped electrode to stop bleeding and kill any cancer cells that may have been left behind in the edges of the wound.

  • Mohs surgery. This procedure removes the cancer and as little normal tissue as possible. It’s done in sensitive areas such as the face. During this surgery, the surgeon removes a thin layer of skin including the cancer, and then uses a microscope to make sure no cancer cells remain. If cancer cells are seen, another layer of skin is removed. This is repeated until all of the cancer has been removed.

  • Cryosurgery. This procedure uses liquid nitrogen to freeze the tumor and kill cancer cells.

  • Laser therapy. The surgeon uses a narrow beam of intense light to remove cancer cells.

  • Skin grafting after surgery. The surgeon takes a skin graft from another part of the body to replace skin where the cancer was removed.


Chemotherapy is done with medicines. With nonmelanoma skin cancer, chemotherapy is most often done by applying strong medicine to the skin to kill cancer cells. Basal cell cancer rarely spreads, and IV or oral medicine is not often used for it. Squamous cell cancer can sometimes spread. If this happens, medicines may be given through an IV or by mouth.

Targeted therapy

Targeted therapy is also done with medicine, but it works differently than regular chemotherapy. It also can have different side effects. The medicine targets specific parts of cancer cells. In rare cases of advanced basal cell cancer, or where surgery or radiation can’t be used, a basal cell cancer may be treated with a targeted medicine.

Radiation therapy

Radiation therapy uses high energy X-rays or other types of radiation. The goal of this treatment is to kill cancer cells. In some cases, this treatment is used instead of surgery. It can also be used to get rid of any cancer cells that may be left after surgery.

Photodynamic therapy

The goal of this treatment is to kill cells at the tumor site by using a medicine to make the cells more sensitive to a special laser light. This limits damage to healthy tissue. This therapy is sometimes used for nonmelanoma skin cancer. For more information, ask your doctor about this therapy.

Biologic therapy

This type of therapy is done with medicines. The medicines use chemicals that affect the immune system. It is also called immunotherapy, antibody therapy, or vaccine therapy. The medicine uses your body’s immune defense to attack the cancer cells. The treatments can be given as a cream that is applied on the tumor. Or it can be given as an injection into the tumor.

Clinical trials for new treatments

Researchers are always finding new ways to treat cancer. These new methods are tested in clinical trials. Talk with your doctor to find out if there are any clinical trials you should consider.

Talking with your healthcare provider

At first, thinking about treatment options may seem overwhelming. Talk with your doctors, nurses, and loved ones. Make a list of questions. Consider the benefits and possible side effects of each option. Discuss your concerns with your doctor before making a decision.