Skin Cancer
Skin cancer is cancer that starts as a growth of cells on the skin. The cells can invade and destroy healthy body tissue. Sometimes the cells break away and spread to other parts of the body.
Many kinds of skin cancer exist. The most common skin cancers are basal cell carcinoma and squamous cell carcinoma. While these are the most common, they often can be cured. The most dangerous form of skin cancer is melanoma. It is more likely to spread, making it harder to cure.
Most skin cancers happen on skin that gets a lot of sunlight. The light that comes from the sun is thought to cause most skin cancers. You can reduce your risk of skin cancer by covering your skin with clothes or sunscreen to protect it from the sun.
Some skin cancers happen on skin that doesn’t typically get sun. This likely means that something else is causing these cancers. To reduce your risk of these kinds of skin cancers, check your skin regularly for any changes. Report these changes to your healthcare professional.
Most skin cancers are caused by exposure to light from the sun. The light that comes from the sun is a kind of ultraviolet light. That kind of light also can come from tanning beds and tanning lamps. Ultraviolet light contains radiation that changes the DNA inside skin cells and leads to skin cancer.
Not all skin cancers happen on skin that typically gets a lot of sun. This means something else also causes skin cancer. It’s not always clear what causes skin cancer. But healthcare professionals have found some things that increase the risk. These include having a weakened immune system and having a family history of skin cancer.
Skin cancer starts when skin cells develop changes in their DNA. A cell’s DNA holds the instructions that tell the cell what to do. In healthy cells, the DNA tells the cells to grow and multiply at a set rate. The DNA also tells the cells to die at a set time.
In cancer cells, the DNA changes give different instructions. The changes tell the cancer cells to grow and multiply quickly. Cancer cells can keep living when healthy cells would die. This causes too many cells.
The cancer cells can invade and destroy healthy body tissue. In time, cancer cells can break away and spread to other parts of the body. When cancer spreads, it’s called metastatic cancer.
Basal cell carcinoma on white skin
Basal cell carcinoma is a type of skin cancer that most often develops on areas of skin exposed to the sun, such as the face. On white skin, basal cell carcinoma often looks like a bump that’s skin-colored or pink.
Basal cell carcinoma on brown skin
Basal cell carcinoma is a type of skin cancer that most often develops on areas of skin exposed to the sun, such as the face. On brown and Black skin, basal cell carcinoma often looks like a bump that’s brown or glossy black and has a rolled border.
Squamous cell carcinoma of the skin
Sun-exposed areas such as the lower lip and ears are most likely to develop squamous cell carcinoma of the skin.
Signs and symptoms of skin cancer include:
- A new growth on the skin that might look like a mole, a bump or a scab.
- A rough patch on the skin.
- A sore on the skin that won’t heal.
- Changes to a mole or freckle, such as getting bigger or changing color.
- Itchy skin around a skin growth.
- Pain around a skin growth.
A skin cancer diagnosis often starts with an exam of your skin. A healthcare professional might remove some skin to test it for cancer.
Skin cancer exam
A healthcare professional might start by asking about your symptoms and looking at your skin.
Lichen planus is usually not harmful. Most often, it gets better with treatment. The condition often clears up within 18 months, but may come and go for years.
If lichen planus is caused by a medicine you are taking, the rash should go away once you stop the medicine.
Treatment for skin cancer can involve surgery to remove the cancer or treatments applied to the skin to kill the cancer cells. Sometimes stronger cancer treatments are needed for skin cancer. These might include radiation therapy, chemotherapy, targeted therapy and immunotherapy.
Skin cancer treatments can include:
- Skin creams. Some medicines for skin cancer come as skin creams that you apply to the area of cancer.
- Curettage and electrodessication. This treatment involves removing the top of the skin cancer with a scraping tool called a curet. Then an electric needle is used to sear the base of the cancer.
- Photodynamic therapy. Photodynamic therapy is a two-stage treatment that combines light energy with a medicine called a photosensitizer. The photosensitizer kills the cancer cells when activated by light.
- Surgery. Skin cancer surgery often involves removing the cancer and some of the healthy tissue around it.
- Mohs surgery. Mohs surgery involves removing the skin cancer layer by layer. Each time a layer is removed, the surgeon uses a microscope to look for cancer cells. The surgery continues until no cancer cells are left. This kind of surgery lets the surgeon take out the cancer without removing too much of the healthy skin around it.
- Radiation therapy. Radiation therapy treats cancer with powerful energy beams.
- Chemotherapy. Chemotherapy treats cancer with strong medicines.
- Targeted therapy. Targeted therapy for cancer is a treatment that uses medicines that attack specific chemicals in the cancer cells. By blocking these chemicals, targeted treatments can cause cancer cells to die.
- Immunotherapy. Immunotherapy for cancer is a treatment with medicine that helps the body’s immune system kill cancer cells. The immune system fights off diseases by attacking germs and other cells that shouldn’t be in the body. Cancer cells survive by hiding from the immune system. Immunotherapy helps the immune system cells find and kill the cancer cells.
- Basal cell carcinoma
- Melanoma
- Nonmelanoma skin cancer
- Squamous cell carcinoma of the skin
Your healthcare professional likely will ask about your symptoms. Be ready to answer questions such as:
- When did you first notice your skin changes?
- Have you noticed a skin lesion that has grown or changed?
- Do you have a skin lesion that bleeds or itches?
- How bad are your symptoms?
Most skin cancers can be prevented by protecting yourself from the sun. To lower the risk of skin cancer you can:
- Stay out of the sun during the middle of the day. For much of North America, the sun’s rays are strongest between about 10 a.m. and 3 p.m. Plan outdoor activities at other times of the day. When outside, stay in shade as much as possible.
- Wear sunscreen year-round. Use a broad-spectrum sunscreen with an SPF of at least 30, even on cloudy days. Apply sunscreen generously. Apply again every two hours, or more often if you’re swimming or sweating.
- Wear protective clothing. Wear dark, tightly woven clothes that cover your arms and legs. Wear a wide-brimmed hat that shades your face and ears. Don’t forget sunglasses.
- Don’t use tanning beds. The lights in tanning beds give off ultraviolet light. Using tanning beds increases the risk of skin cancer.
Check your skin often and report changes to your healthcare team. Look at your skin often for new growths. Look for changes in moles, freckles, bumps and birthmarks. Use mirrors to check your face, neck, ears and scalp.
Look at your chest and trunk and the tops and undersides of your arms and hands. Look at the front and back of your legs and your feet. Look at the bottom of the feet and the spaces between your toes. Also check your genital area and between your buttocks.
Factors that may increase the risk of skin cancer include:
- Skin that sunburns easily. Anyone of any skin color can get skin cancer. But the risk is higher in people with skin that sunburns easily. The risk of skin cancer also is higher in people who have blond or red hair, light-colored eyes or freckles.
- Light from the sun. Ultraviolet light from the sun increases the risk of skin cancer. Covering the skin with clothes or sunblock can help lower the risk.
- Light from tanning beds. People who use indoor tanning beds have an increased risk of skin cancer. The lights used in tanning beds give off harmful ultraviolet light.
- A history of sunburns. Having had one or more sunburns that raised blisters increases the risk of developing skin cancer. If the sunburns happened during childhood, they increase the risk of getting skin cancer as an adult even more.
- A history of skin cancer. People who’ve had skin cancer once are much more likely to get it again.
- A family history of skin cancer. If a blood relative, such as a parent or sibling, had skin cancer, you may be more likely to get skin cancer.
- A weakened immune system. If the body’s germ-fighting immune system is weakened by medicine or disease, there might be a higher risk of skin cancer. People with weakened immune systems include those taking medicine to control the immune system, such as after an organ transplant. Some health conditions, such as HIV infection, also can weaken the immune system.
References
Niederhuber JE, et al., eds. Nonmelanoma skin cancers: Basal cell and squamous cell carcinomas. In: Abeloff’s Clinical Oncology. 6th ed. Elsevier; 2020. https://www.clinicalkey.com. Accessed Dec. 5, 2024.
DeVita VT Jr, et al., eds. DeVita, Hellman, and Rosenberg’s Cancer: Principles and Practice of Oncology. 12th ed. Wolters Kluwer; 2023. Accessed Dec. 5, 2024.
Skin cancer treatment (PDQ) — Patient version. National Cancer Institute. https://www.cancer.gov/types/skin/patient/skin-treatment-pdq. Accessed Dec. 4, 2024.
Skin cancer prevention (PDQ) — Patient version. National Cancer Institute. https://www.cancer.gov/types/skin/patient/skin-prevention-pdq. Accessed Dec. 4, 2024.
Skin cancer basics. Centers for Disease Control and Prevention. https://www.cdc.gov/skin-cancer/about/index.html. Accessed Dec. 15, 2024.
Find skin cancer: How to perform a skin self-exam. American Academy of Dermatology. https://www.aad.org/public/diseases/skin-cancer/find/check-skin. Accessed Dec. 15, 2024.
How can I tell if I have skin cancer? American Academy of Dermatology. https://www.aad.org/public/diseases/skin-cancer/find/know-how. Accessed Dec. 4, 2024.
Dinulos JGH. Premalignant and malignant nonmelanoma skin tumors. In: Habif’s Clinical Dermatology. 7th ed. Elsevier; 2021. https://www.clinicalkey.com. Accessed Dec. 5, 2024.
Fowler GC, et al., eds. Approach to various skin lesions. In: Pfenninger and Fowler’s Procedures for Primary Care. 4th ed. Elsevier; 2020. https://www.clinicalkey.com. Accessed Dec. 9, 2024.
American College of Surgeons. AJCC Cancer Staging System. American College of Surgeons; 2023. https://online.statref.com. Accessed Dec. 9, 2024.
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