According to the American Cancer Society, skin cancer is the most common type of cancer in the United States. Skin cancer is an abnormal growth of skin cells. It generally develops in areas that are exposed to the sun, but it can also form in places that don’t normally get sun exposure.
The two main categories of skin cancers are defined by the cells involved. The first category is basal and squamous cell skin cancers. These are the most common forms of skin cancer. They’re most likely to develop on areas of your body that get the most sun, like your head and neck. They’re less likely than other forms of skin cancer to spread and become life-threatening. But if left untreated, they can grow larger and spread to other parts of your body.
The second category of skin cancers is melanoma. They develop from cells that give your skin color. These cells are known as melanocytes. Benign moles formed by melanocytes can become cancerous. They can develop anywhere on your body. In men, these moles are more likely to develop on the chest and back. In women, these moles are more likely to develop on the legs.
Most melanomas can be cured if they’re identified and treated early. If left untreated, they can spread to other parts of your body and become harder to treat. Melanomas are more likely to spread than basal and squamous cell skin cancers.
Causes of skin cancer
Both types of skin cancer occur when mutations develop in the DNA of your skin cells. These mutations cause skin cells to grow uncontrollably and form a mass of cancer cells.
Basal cell skin cancer is caused by ultraviolet (UV) rays from the sun or tanning beds. UV rays can damage the DNA inside your skin cells. Squamous cell skin cancer is also caused by UV exposure. Squamous cell skin cancer can also develop after long-term exposure to cancer-causing chemicals. It can develop within a burn scar or ulcer, and may also be caused by some types of human papillomavirus (HPV).
The cause of melanoma is unclear. Most moles don’t turn into melanomas, and researchers aren’t sure why some do. Like basal and squamous cell skin cancers, melanoma can be caused by UV rays. But melanomas can develop in parts of your body that aren’t typically exposed to sunlight.
Risk factors for skin cancer
Certain factors raise your risk of developing skin cancer. For example, you’re more likely to get skin cancer if you:
- have a family history of skin cancer
- are exposed to certain substances, like arsenic compounds, radium, pitch, or creosote
- are exposed to radiation, for example, during certain treatments for acne or eczema
- get excessive or unprotected exposure to UV rays from the sun, tanning lamps, tanning booths, or other sources
- live or vacation in sunny, warm, or high-altitude climates
- have a history of severe sunburns
- have multiple, large, or irregular moles
- have skin that’s pale or freckled
- have skin that sunburns easily or doesn’t tan
- have natural blond or red hair
- have blue or green eyes
- have precancerous skin growths
- have a weak immune system, for example, from HIV or AIDS
- have had an organ transplant and take immunosuppressant medication
Diagnosing skin cancer
If you develop suspicious spots or growths on your skin, or you notice changes in existing spots or growths, make an appointment with your doctor. You doctor will examine your skin or refer you to a specialist for diagnosis.
Your doctor or specialist will likely examine the shape, size, color, and texture of the suspicious area on your skin. They will also check for scaling, bleeding, or dry patches. If your doctor suspects it might be cancerous, they may perform a biopsy. During this safe and simple procedure, they will remove the suspicious area to send to a lab for testing. This can help them learn if you have skin cancer.
If you’re diagnosed with skin cancer, you may need additional tests to learn how far it has progressed. Your recommended treatment plan will depend on the type and stage of your skin cancer, as well as other factors.
Types of doctors who treat skin cancer
If you’re diagnosed with skin cancer, your doctor may assemble a team of specialists to help address different aspects of your condition. For example, your team may include one or more of the following:
- a dermatologist who treats skin diseases
- a surgical oncologist or oncologic surgeon who treats cancer using surgery
- a radiation oncologist who treats cancer using radiation therapy
- a medical oncologist who treats cancer using targeted therapy, immunotherapy, chemotherapy, or other medications
You may also receive support from other health care providers, such as:
- nurse practitioners
- physician assistants
- social workers
- nutrition specialists
Treatments for skin cancer
Your recommended treatment plan will depend on different factors, like the size, location, type, and stage of your skin cancer. After considering these factors, your healthcare team may recommend one or more of the following treatments:
- cryotherapy: The growth is frozen using liquid nitrogen and the tissue is destroyed as it thaws.
- excisional surgery: The growth and some of the healthy skin surrounding it are cut out.
- Mohs’ surgery: The growth is removed layer by layer, and each layer is examined under a microscope until no abnormal cells are visible.
- curettage and electrodessication: A long spoon-shaped blade is used to scrape away the cancer cells, and the remaining cancer cells are burned using an electric needle.
- chemotherapy: Drugs are taken orally, applied topically, or injected with a needle or IV line to kill the cancer cells.
- photodynamic therapy: A laser light and drugs are used to destroy the cancer cells.
- radiation: High-powered energy beams are used to kill the cancer cells.
- biological therapy: Biological treatments are used to stimulate your immune system to fight the cancer cells.
- immunotherapy: A cream is applied to your skin to stimulate your immune system to kill the cancer cells.
Ask your doctor for more information about your treatment options.
Complications of skin cancer
Potential complications of skin cancer include:
- recurrence, where your cancer comes back
- local recurrence, where cancer cells spread to surrounding tissues
- metastasis, where cancer cells spread to muscles, nerves, or other organs in your body
If you’ve had skin cancer, you’re at heightened risk of developing it again in another location. If your skin cancer recurs, your treatment options will depend on the type, location, and size of the cancer, and your health and prior skin cancer treatment history.
Preventing skin cancer
To lower your risk of skin cancer, avoid exposing your skin to sunlight and other sources of UV radiation for extended periods of time. For example:
- Avoid tanning beds and sun lamps.
- Avoid direct sun exposure when the sun is strongest, from 10 a.m. to 4 p.m., by staying indoors or in the shade during those times.
- Apply lip balm and sunscreen with a sun protection factor (SPF) of 30 or higher to any exposed skin at least 30 minutes before heading outdoors, and reapply regularly.
- Wear a wide-brimmed hat and dry, dark, tightly woven fabrics when you’re outside during daylight hours.
- Wear sunglasses that offer 100 percent UVB and UVA protection.
It’s also important to regularly examine your skin for changes like new growths or spots. Tell your doctor if you notice anything suspicious.
If you develop skin cancer, identifying and treating it early can help improve your long-term outlook.