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Skin Cancer, Non-Melanoma

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This topic is about non-melanoma skin cancer, including basal cell cancer and squamous cell cancer. For information about melanoma skin cancer, see the topic Skin Cancer, Melanoma.

What is non-melanoma skin cancer?

Skin cancer is the abnormal growth of cells in the skin. It is the most common type of cancer. It is almost always cured when it is found early and treated. So it is important to see your doctor if you have changes in your skin.

Most skin cancers are the non-melanoma type. There are two main types of non-melanoma skin cancer:

  • Basal cell carcinoma. Most non-melanoma cancers are this type. It can damage deeper tissues, such as muscles and bones. It almost never spreads to other parts of the body.
  • Squamous cell carcinoma. This type is less common. It often develops from a small rough spot that grows in sun-damaged skin. It sometimes spreads to other parts of the body.

There are other types of skin cancer that are not melanoma. But these are much less common. They include Merkel cell carcinoma and several kinds of sarcomas.

What causes it?

Non-melanoma skin cancer is usually caused by too much sun. Using tanning beds or sunlamps too much can also cause it.

How is non-melanoma skin cancer diagnosed?

Skin cancer usually appears as a growth that changes in colour, shape, or size. This can be a sore that does not heal or a change in a mole or skin growth. These changes usually happen in areas that get the most sun—your head, neck, back, chest, or shoulders. The most common place for skin cancer is your nose.

Your doctor will use a biopsy to find out if you have skin cancer. This means taking a sample of the growth and sending it to a lab to see if it contains cancer cells.

What increases your risk for non-melanoma skin cancer?

The single greatest risk is from ultraviolet (UV) radiation. This comes from exposure to the sun, especially during the middle of the day. It also comes from exposure to artificial sources of UV, such as indoor tanning.

If you have light skin that sunburns easily, you are more likely to get skin cancer.

Your risk is higher if you are male or if you are over 40. Your risk is higher if others in your family have had it or if you have had it before.

You may also be more likely to get it if you have been exposed often to strong X-rays, to certain chemicals (such as arsenic, coal tar, and creosote), or to radioactive substances (such as radium).

How is it treated?

Your doctor will want to remove all of the cancer. There are several ways to do this. The most common way is to numb your skin so that it does not hurt, then cut out the cancer. You will be awake while this is done.

This surgery almost always cures non-melanoma skin cancer. Other treatments include radiation, medicines that are put on the skin (topical therapies), and photodynamic therapy (PDT).

After your treatment, you will need regular checkups, because having skin cancer once means you are more likely to get it again.

Can non-melanoma skin cancer be prevented?

You can prevent it by being careful in the sun. Stay out of the sun at midday, when the sun's rays are strongest. Wear sunscreen or other sun protection. Do not use tanning booths or sunlamps.

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    Cause

    Non-melanoma skin cancer is usually caused by overexposure to the sun and its ultraviolet (UV) rays. Overexposure to UV rays can result from:

    • Having severe sunburn and blistering, especially during childhood.
    • Spending a lot of time in the sun over many years.
    • Using tanning beds or sunlamps, which are artificial sources of UV rays.

    Other possible causes of skin cancer include repeated exposure to X-rays, certain chemicals (such as arsenic, coal tar, creosote), and radioactive substances (such as radium). Skin cancer may also be caused by ionizing radiation treatments for skin conditions such as psoriasis or acne.

    Symptoms

    Non-melanoma skin cancer may appear as a change in the skin, such as a growth, an irritation or sore that does not heal, or a change in a mole or a skin growth.

    Basal cell carcinoma usually affects the head, neck, back, chest, or shoulders. The nose is the most common site. Signs of basal cell carcinoma can vary depending on the type and may include skin changes such as a:

    • Firm, pearly bump with tiny blood vessels that look spidery (telangiectasias).
    • Red, tender, flat spot that bleeds easily.
    • Small, fleshy bump with a smooth, pearly appearance, often with a depressed centre.
    • Smooth, shiny bump that may look like a mole or cyst.
    • Patch of skin, especially on the face, that looks like a scar and is firm to the touch.
    • Bump that itches, bleeds, crusts over, and then repeats the cycle and has not healed in a few weeks.
    • Change in the size, shape, or colour of a mole or a skin growth.

    Squamous cell carcinoma usually affects the face, head, or neck. Signs of squamous cell carcinoma include any:

    • Persistent, firm, red bump on sun-exposed skin.
    • Patch of skin that feels scaly, bleeds, or develops a crust. The patch may get bigger over a period of months and form a sore.
    • Skin growth that looks like a wart.
    • Sore that does not heal or an area of thickened skin on the lower lip, especially if you smoke or use chewing tobacco or your lips are often exposed to the sun and wind.

    Other conditions, such as actinic keratosis, may have symptoms similar to skin cancer. It is important to have any new or persistent skin change evaluated by your doctor.

    What Happens

    Non-melanoma skin cancer usually develops slowly, invading and destroying nearby tissues. It may take months or years for basal cell or squamous cell carcinomas to develop. Because of this slow growth, skin cancer can often be detected and treated early in its development, increasing the chance for a cure.

    Basal cell carcinoma

    Basal cell carcinoma can affect the surface of the skin where it appears. If it is not treated, it can grow larger and cause problems beneath the skin, sometimes damaging the muscles and bones. Basal cell carcinoma very rarely spreads (metastasizes) to other parts of the body.

    After you have one basal cell carcinoma, you are more likely to have another one develop in a new place. If basal cell carcinoma comes back at the same place (recurs), it may grow faster and cause more tissue damage.

    Squamous cell carcinoma

    Squamous cell carcinoma may grow from a small rough spot in sun-damaged skin (actinic keratosis). But this isn't common. Or it may develop from an early form of skin cancer called Bowen's disease. If a squamous cell carcinoma is not treated, it may spread.

    What Increases Your Risk

    Risk factors (things that increase your risk) for non-melanoma skin cancer include:

    • Sunlight, sunlamps, or tanning beds. These expose you to ultraviolet (UV) radiation.
      • UV radiation affects people of all skin types, but especially those with light skin colour, freckles, blond or red hair, and blue or light-coloured eyes.
      • Living where you get high levels of UV radiation. People living closer to the equator get more UV radiation. And people who live at higher altitudes, such as in the mountains, get more UV radiation.
    • A family history of skin cancer or a personal history of skin cancer. Or other things that affect your skin, such as:
      • Inherited genetic disorders, such as xeroderma pigmentosum.
      • A history of severe sunburns, especially during childhood.
      • Scars from severe burns or inflammatory skin conditions.
    • Being older than 40.
    • Being male. Men develop skin cancer more often than women.
    • Smoking.
    • Repeated exposure to X-rays, certain chemicals (such as arsenic, coal tar, creosote), and radioactive substances (such as radium).
    • Being infected with a certain type of human papillomavirus (HPV).

    Basal cell and squamous cell carcinomas can occur in people with dark skin. But these cancers are much more common in people with light skin.

    The risk of squamous cell carcinoma is higher in people who have weakened immune systems. This includes people who have had organ transplants and take medicines to prevent rejection of the new organ.

    When should you call your doctor?

    Call your doctor if you have an irritated or irregular skin growth. This includes any:

    • Firm, pearly bump with tiny blood vessels that look spidery (telangiectasias).
    • Red, tender, flat spot that bleeds easily.
    • Small, fleshy bump with a smooth, pearly appearance, often with a depressed centre.
    • Smooth, shiny bump that may look like a mole or cyst.
    • Patch of skin, especially on the face, that looks like a scar and is firm to the touch.
    • Bump that itches, bleeds, crusts over, and then repeats the cycle and has not healed in 3 weeks.
    • Change in a mole or a skin growth, including a change in size, shape, or colour.
    • Area of normal skin that quickly changes shape or appearance.

    Be sure to show your doctor any skin growths that concern you so that they can be evaluated and treated if needed.

    Who to see

    Your family doctor or general practitioner can examine and diagnose a suspicious skin growth.

    You may be referred to a specialist who can remove a large skin growth or one in a noticeable area while minimizing scars that may result from surgery. These specialists include:

    Examinations and Tests

    Non-melanoma skin cancer is diagnosed by:

    • Your medical history. Your doctor will ask when the skin change occurred, whether you have been exposed to substances (such as arsenic) that can cause skin cancer, and whether you have any personal or family history of skin cancer.
    • A physical examination of the skin growth. Your doctor can often tell what a skin growth is by looking at it. He or she may decide to monitor changes in the skin growth or take a sample of the skin growth for further testing.
    • A skin biopsy. This is usually done when an area of skin has changed colour, shape, size, or appearance or has not healed and skin cancer is suspected. A skin biopsy also may be done if the cause of a skin problem is not easily identified.

    Early detection

    Take steps to detect skin cancer early:

    • Examine your skin once a month, and ask your doctor to look at any suspicious skin growths.
    • Talk to your doctor about your own personal risk for skin cancer so that you understand the precautions that you need to take.
    • Have your doctor look for any suspicious skin growths during any health examination.

    Treatment Overview

    The goals of treatment for non-melanoma skin cancer are to:

    • Remove the entire skin cancer and a margin of skin tissue around the cancer to reduce the chance of recurrence.
    • Preserve nearby skin tissue that is free of cancer and minimize scarring after surgery.

    Initial treatment

    Treatment for non-melanoma skin cancer depends on the size and location of the cancer, whether it is basal cell or squamous cell, and your age and overall health. The type of treatment will also depend on whether you have had skin cancer at that place before and whether the cancer is in a place where you have had radiation therapy. Because skin cancer usually grows slowly, it often can be detected early and successfully treated.

    The most common treatment is surgery to destroy or remove the entire skin growth, including a margin of cancer-free tissue around the growth. Most surgical treatments are very effective, with high cure rates.

    The main treatment options are:

    • Mohs micrographic surgery. This surgery removes the skin cancer one layer at a time, checking each layer for cancer cells right after it is removed.
    • Excision. Excision removes the skin cancer along with some healthy skin tissue around it (margin).
    • Radiation therapy. Radiation therapy uses X-rays or other types of radiation to kill cancer cells. It may done if surgery isn't an option.
    • Curettage and electrosurgery. Curettage uses a spoon-shaped instrument (curette) to scrape off the skin cancer, and electrosurgery controls the bleeding and destroys any remaining cancer cells.
    • Cryosurgery. Cryosurgery destroys the skin cancer by freezing it with liquid nitrogen.

    Each of these treatments has advantages and disadvantages. Discuss your options with your doctor.

    • Basal Cell Skin Cancer: Should I Have Surgery or Use Medicated Cream?

    Basal cell carcinoma may also be treated with:

    • Photodynamic therapy.
    • Medicines put on the skin, such as topical fluorouracil (5-FU) and topical imiquimod.
    • Laser surgery.

    Ongoing treatment

    Follow-up treatment for non-melanoma skin cancer includes skin self-examinations and regular examinations by your doctor. These examinations are extremely important to reduce the risk of the cancer coming back (recurrence).

    Almost half of people who have a non-melanoma skin cancer will develop another one within 5 years.footnote 1 Your doctor may schedule you for examinations as often as every 3 to 6 months for the first 2 years and yearly after that, especially for squamous cell carcinoma.

    Treatment if the condition gets worse

    Surgery is usually very effective for both basal and squamous cell carcinoma. But sometimes the cancer can come back (recur). Or in rare cases, it may spread (metastasize). Metastasis is more likely with squamous cell carcinoma than with basal cell.

    If basal cell carcinoma comes back, treatment is usually Mohs surgery. But for squamous cell carcinoma that comes back, treatment may include surgery (excision or Mohs surgery) or radiation therapy.

    If the cancer does spread, chemotherapy may be used. If basal cell carcinoma spreads after treatment with surgery and radiation, it may be treated with medicines like vismodegib (Erivedge). Your doctor may suggest that you enroll in a clinical trial if one is available.

    What to think about

    Precancer skin growths, such as actinic keratoses and Bowen's disease, can develop into squamous cell skin cancer if they are not treated.

    You can find more information about skin cancer online at the:

    Prevention

    Most non-melanoma skin cancer can be prevented by protecting your skin from the sun and ultraviolet (UV) radiation.

    • Limit your exposure to the sun, especially from 11 a.m. to 3 p.m., the hours of peak ultraviolet exposure.
    • Wear protective clothing, including a wide-brimmed hat, a long-sleeved shirt, and pants.
    • Wear sunglasses that block UV rays.
    • Use a broad-spectrum sunscreen that has a sun protection factor (SPF) of at least 30. A broad-spectrum sunscreen protects the skin from both UVA and UVB rays.
    • Use lip balm or cream that has sun protection factor (SPF) to protect your lips from getting sunburned.
    • Avoid tanning booths and sunlamps, which emit UV radiation and can cause skin damage.

    Skin protection for children

    Children and babies should be protected from the sun. You should start protecting your child from the sun when he or she is a baby. Because children and teens spend a lot of time outdoors playing, they get most of their lifetime sun exposure in their first 18 years.

    • Teach your children that it is important to protect their skin from the sun.
    • Have your children wear protective clothing, sunglasses, and a hat with a wide brim when they are in the sun.
    • Have your children wear sunscreen. Choose a sunscreen with SPF 30 or higher. Follow the instructions on the sunscreen. Put sunscreen on your skin 20 minutes before you go out and reapply 20 minutes after being out in the sun. This helps ensure you applied the sunscreen evenly and that you are better protected. Reapply sunscreen after 2 hours in the sun or water, even if the sunscreen is waterproof.
    • Keep babies younger than 12 months out of direct sunlight. Do not use sunscreen on babies younger than age 6 months.

    Some people believe that a tan may protect them against a sunburn and skin damage. But the amount of sun exposure needed to get a tan can by itself cause skin damage.

    Home Treatment

    Home treatment after a skin cancer is removed includes regular use of skin protection measures to prevent a return (recurrence) of non-melanoma skin cancer and regular examinations to watch for suspicious skin changes.

    Perform a skin self-examination once a month.

    • Check your skin and skin growths for any changes in colour, shape, size, or appearance.
    • Look for any diseased area of skin that has not healed.
    • Report any suspicious changes in your skin to your doctor.

    Certain medicines, such as some antibiotics or diuretics, can make your skin more sensitive to the sun's rays. Ask your doctor about this potential side effect of your medicines, and take extra precautions if needed.

    Medications

    Medicines are rarely used to treat non-melanoma skin cancer. Surgery is the most common and the most effective treatment. But when surgery is not possible, your doctor may suggest medicines. Medicines may also be used when a skin cancer is too large for surgery or when new skin cancers keep appearing.

    Medicine choices

    Medicines that may be used to treat basal cell carcinoma include:

    • Fluorouracil (5-FU). This cream or lotion is used to treat carcinomas that are only in the top layer of skin (superficial).
    • Imiquimod (Aldara). Imiquimod is used to treat superficial basal cell cancer on the skin of the body, neck, arms, or legs, but it is not approved for treating the face.

    Medicines that may be used to treat squamous cell carcinoma include:

    • Fluorouracil (5-FU). This cream or lotion is used to treat superficial carcinomas.
    • Tretinoin (Retin-A) cream. Along with this cream, you may be given isotretinoin pills.
    • Interferon may be given to help your immune system fight the cancer. This is given by injection (shot).

    People treated with medicines will need to have regular follow-up visits with their doctors to make sure the skin cancer is gone.

    Chemotherapy may be used to destroy cancer cells in the small number of people who have basal cell or squamous cell carcinoma that has spread (metastasized) to other organs in the body, though metastasis is rare.

    What to think about

    Medicines such as 5-FU and imiquimod may cause your skin to be sore. Your skin may turn red, swell, itch, or break out in a rash. Your skin may also be sensitive to sunlight. If your skin turns too red or raw, your doctor may stop the treatment.

    Surgery

    Surgery is the most common and most successful method of treating non-melanoma skin cancer. The goals of surgery are to:

    • Remove the entire skin cancer and a margin of healthy skin tissue around the cancer to reduce the chance of recurrence.
    • Preserve nearby skin tissue that is free of cancer and minimize scarring after surgery.

    Surgery choices

    The main types of surgery for non-melanoma skin cancer include:

    • Mohs micrographic surgery. This surgery removes the skin cancer one layer at a time, checking each layer for cancer cells right after it is removed.
    • Excision. Excision removes the skin cancer along with some healthy skin tissue around it (margin).
    • Curettage and electrosurgery. Curettage uses a spoon-shaped instrument (curette) to scrape off the skin cancer, and electrosurgery controls the bleeding and destroys any remaining cancer cells.

    Other types of surgery that may be done include:

    • Cryosurgery. Cryosurgery destroys the skin cancer by freezing it with liquid nitrogen.
    • Laser surgery. Lasers use an intense beam of light to remove skin cancer.
    • Dermabrasion. Dermabrasion scrapes off cancer cells in the top layer of skin using a swirling wire brush or small particles.

    Each type of treatment has advantages and disadvantages. Discuss your options with your doctor.

    • Basal Cell Skin Cancer: Should I Have Surgery or Use Medicated Cream?

    What to think about

    If squamous cell carcinoma has spread to the lymph nodes, surgery to remove the affected lymph nodes (lymphadenectomy) may be done. Radiation or chemotherapy may be recommended after surgery.

    Other Treatment

    Radiation therapy may be used to treat skin cancers in some cases. It may also be recommended for people who may not be able to have surgery because of the location of the skin cancer. Radiation therapy may also be a treatment choice if age or other health conditions make surgery too risky. Radiation therapy is most often used for older adults. It may lead to other skin cancers in younger people as they age.

    Radiation therapy may be an effective treatment for people who have low-risk, shallow cancers, such as squamous cell carcinoma in situ (Bowen's disease).

    Other treatments for people who cannot have surgery or radiation include photodynamic therapy (PDT), which uses medicines and a special light to treat skin cancer on or very close to the surface of the skin.

    References

    Citations

    1. National Comprehensive Cancer Network (2010). Basal cell and squamous cell skin cancers. NCCN Clinical Practice Guidelines in Oncology, Version 1. Available online: http://www.nccn.org/professionals/physician_gls/PDF/nmsc.pdf.

    Credits

    Current as of: September 8, 2021

    Author: Healthwise Staff
    Medical Review:
    E. Gregory Thompson MD - Internal Medicine
    Brian D. O'Brien MD - Internal Medicine
    Adam Husney MD - Family Medicine
    Kathleen Romito MD - Family Medicine
    Amy McMichael MD - Dermatology