Nonmelanoma Skin Cancer: Introduction

Getting a cancer diagnosis

It can be shocking to learn that you or someone you care for has cancer. Feeling upset or nervous when you get this kind of news is only natural. But remember: You are not alone on this journey. And even though a diagnosis can be scary, it’s the first step toward treatment.

What is nonmelanoma skin cancer?

Cancer starts when cells in the body change and grow out of control. Most cancers involve a lump or mass of these abnormal cells. This is also known as a tumor. If cancer cells go undetected for long enough, they might spread into nearby tissues or other parts of the body. This process is called metastasis.

Skin cancer develops in the cells of the skin and often appears as a new flat, scaly patch or raised shiny bump that grows over time. Depending on your skin tone, the lesion may appear pink, red, brown, or black. There are several types of skin cancer. The most common kinds of skin cancer are nonmelanoma skin cancers. The most common subtypes are:

• Basal cell carcinoma

• Squamous cell carcinoma

There are other types of nonmelanoma skin cancer, but they are much less common. Some examples include:

• Merkel cell carcinoma

• Cutaneous (skin) lymphoma

• Kaposi sarcoma

Understanding the skin

The skin is the largest organ of the body. It serves as a protective barrier and is one of our first lines of defense against infections. It also protects us from heat, sunlight, and injury. Skin helps regulate temperature and water loss. It also stores water and fat, and makes vitamin D. The skin has 3 layers:

• The outer layer called the epidermis. The epidermis consists of 5 layers and 4 main cell types (keratinocytes, melanocytes, Merkel cells, and Langerhans cells).

• The middle layer called the dermis. The dermis consists of 2 main layers. It contains the sweat glands, hair and hair follicles, muscles, nerves, and blood vessels.

• The inner, deep layer called the hypodermis, or subcutaneous tissue. This is the deepest layer of skin. It contains fat tissue and also hair follicles, nerves, and blood vessels.

Most nonmelanoma skin cancers start in the epidermis. The most common cells in the epidermis are keratinocytes. Keratinocyte carcinomas include 2 subtypes: basal cell and squamous cell carcinomas.

What are the different types of nonmelanoma skin cancer?

Basal cell carcinoma

Basal cell carcinoma is by far the most common type of skin cancer. As the name implies, basal cell carcinoma starts in the lower part of the epidermis in your skin’s basal cells.

• Where is it commonly found? Sun-exposed areas, like the face, head, neck, arms, and hands

• What does it look like?

  • Small, pink, red raised, shiny, or pearly bump (may have other areas with colors of blue, brown, or black)

  • Crusty, itchy, red patches

  • Flat pale, white, or yellow spots

  • Open sores or ulcers that don't fully heal

Nearly all cases can be cured. It grows slowly and rarely spreads to other parts of your body. Treatment helps prevent this cancer from growing deeper into bone and tissues under the skin, which can cause serious damage. Sometimes, basal cell carcinoma comes back after treatment. And having basal cell carcinoma puts you at higher risk for new ones in other places as well as other types of skin cancer.

Squamous cell carcinoma

Squamous cell carcinoma is the second most common type of skin cancer. It starts in the flat squamous cells in the upper part of the epidermis.

• Where is it commonly found?

  • Sun-exposed areas, like the face, ears, lips, head, neck, arms, and hands

  • Genital area

  • In scars

  • In long-lasting skin sores

• What does it look like? Appearance varies, but it often shows up as a rough, scaly, wart-like, reddish patch on your skin.

Squamous cell carcinoma tends to grow quickly. But this cancer rarely spreads to other parts of the body. Most cases of squamous cell carcinoma are found early enough to be treated and cured.

Merkel cell carcinoma

Merkel cell carcinoma is a very rare type of cancer that most often starts in the skin. It starts deep within the upper layer of your skin. Merkel cells are very close to nerve endings and help your skin sense light touch.

• Where is it commonly found? Sun-exposed areas, such as the head and neck (but it can start anywhere on the body)

• What does it look like? Firm, shiny lumps that don’t hurt. These lumps may be red, pink, purple, or blue.

A Merkel cell cancer tumor tends to grow really fast. So the sooner it is found, the easier it is to treat before it can spread beyond your skin.

Cutaneous lymphoma

Cutaneous lymphomas are a large group of relatively rare and varied immune cell cancers that affect the skin without any evidence of other organ involvement at the time of diagnosis. T cell lymphomas are the most common type of cutaneous lymphomas.

These T cell cutaneous lymphomas often show with skin lesions of variable size and shape that persist or progress over time. They may be localized or form nodules or widespread plaques. They are often itchy and uncomfortable.

Kaposi sarcoma

In Kaposi sarcoma, cancer starts in the cells that line lymph or blood vessels. It can cause lesions on the skin. There are 4 main types of Kaposi sarcoma, but the cancer cells look almost the same in all of them.

• Where are skin lesions commonly found?

  • Legs or feet

  • Face

  • Groin

• What does it look like? Purple, brown, or red patches on the skin in mucous membranes (like the inside of the mouth), or in internal organs

Rely on your healthcare provider

It’s normal to feel uncertain about what comes next. Just remember that you are not alone. If you have questions about nonmelanoma skin cancer, reach out to your healthcare provider. They’re here to help you understand more about your diagnosis and walk with you every step of the way.