article syndicated from NCI

updated about 1 year ago

• Merkel cell cancer is a rare cancer that develops on or just beneath the skin and in hair follicles. It occurs most often on the face, head, and neck.
• Early detection and treatment are important because the disease can spread rapidly. Merkel cell cancer is difficult to cure once it spreads.
• People taking drugs to suppress their immune system after an organ transplant can develop Merkel cell cancer quickly.
• Researchers believe that exposure to sunlight may increase a person’s risk of this disease.

Merkel cell cancer, also called neuroendocrine cancer of the skin or trabecular cancer, is a rare cancer that develops on or just beneath the skin and in hair follicles. It usually appears as firm, painless, shiny skin lumps (nodules), or tumors . These red, pink, or blue tumors vary in size from less than a quarter of an inch to more than 2 inches. About half of all Merkel cell cancers occur on the sun-exposed areas of the head and neck. Another one-third begin on the arms and legs. The cancer may also begin on other parts of the body, such as the trunk.

The cause of Merkel cell cancer is not known. However, researchers have learned that it can develop quickly in people who have had an organ transplant and are taking drugs to suppress their immune system. Exposure to arsenic may also increase the risk for Merkel cell cancer. Because this disease occurs so often on the face, head, neck, and extremities, researchers believe that exposure to sunlight may play a role.

This type of cancer occurs mostly in people after age 70, but it can occur at other ages as well. The majority of patients with Merkel cell cancer are white, and more men than women develop the disease.

It is difficult to diagnose this type of cancer because Merkel cells often resemble cells found in other types of cancers, especially some types of lung cancer. The doctor removes a sample of tissue from the abnormal area, and a pathologist carefully studies the sample under a microscope to check for cancer cells. This procedure is called a biopsy.

The doctor also checks the skin all over the body and examines lymph nodes for signs of swelling. Blood cell counts and a liver function test also help in the diagnosis. In some cases, the doctor may order a CT scan.

Because Merkel cell cancer is uncommon and is difficult to diagnose, patients may want a second opinion about the diagnosis and treatment plan before starting treatment. Some insurance companies require a second opinion; others may pay for a second opinion if a patient requests it.

Surgery is the usual treatment for Merkel cell cancer. The tumor is removed along with a border of healthy tissue. If the tumor is too large to be removed, or is located in a place where removal would be difficult or dangerous, the patient may have radiation or chemotherapy to try to shrink the tumor.

Nearby, or regional, lymph nodes are often removed because they may contain cancer cells. Sometimes the doctor does a sentinel lymph node biopsy. In this procedure, the doctor injects a dye or radioactive substance near the tumor. This material flows into the first lymph nodes where cancer is likely to spread (the sentinel nodes). These nodes are then removed and checked for cancer. Radiation therapy may be directed at the site of the surgery and to nearby lymph nodes to destroy any remaining cancer cells.

Merkel cell cancer grows rapidly and often metastasizes (spreads) to other parts of the body. Even relatively small tumors can metastasize. Merkel cell cancer most often spreads to regional lymph nodes ; it also may spread to the liver, bones, lungs, and brain. Merkel cell cancer that has metastasized may respond to treatment with chemotherapy, but this therapy usually does not cure the disease. Early diagnosis and treatment of Merkel cell cancer are important factors in decreasing the chance of its spread.

The National Cancer Institute (NCI) is a component of the National Institutes of Health (NIH), one of eight agencies that compose the Public Health Service (PHS) in the Department of Health and Human Services (DHHS). The NCI, established under the National Cancer Act of 1937, is the Federal Government’s principal agency for cancer research and training.

article syndicated from NCI

updated about 1 year ago

The words “skin cancer” may conjure up images of potentially deadly melanoma, but nonmelanoma skin cancers are far more common. Though less often lethal, a diagnosis of these cancers is still a cause for concern. Most of these cancers are treated surgically in a doctor’s office so incidence estimates are difficult to determine. However, more than 1 million new cases of nonmelanoma skin cancer may occur each year, and there is evidence that the rates are rising.

BenchMarks recently spoke with Kenneth Kraemer, M.D., and John DiGiovanna, M.D., dermatologists researching skin cancer for the National Cancer Institute’s (NCI) Center for Cancer Research. Dr. Kraemer has a longstanding interest in human cancer-prone genetic diseases and DNA repair. Dr. DiGiovanna’s research has included the basis and treatment of inherited skin disorders; treatment and prevention of skin cancer; retinoids, drugs derived from vitamin A; and other agents. These researchers have collaborated on work with patients who have xeroderma pigmentosum (XP), a disease that increases the risk of skin cancer. An edited transcript of the conversation follows.

We hear a lot about melanoma, but why is nonmelanoma skin cancer prevention research important?

Dr. DiGiovanna: Skin cancer is increasing in epidemic proportions. There are certain subgroups of the population where the frequency is extremely high, such as post-transplant patients. Because of long-term immunosuppression, patients who have had transplants and also have had substantial sun damage are at risk for developing large numbers of skin cancers. In addition, people with inherited conditions such as the nevoid basal cell carcinoma syndrome and XP are also at risk for developing large numbers of skin cancers.

Dr. Kraemer: The nonmelanoma skin cancers are the most common cancers, although they primarily affect Caucasians. These cancers are so common, they’re not actually counted by most surveys of cancer. We’re concerned because skin cancer is caused by sunlight exposure. If we teach children to protect themselves at an early age, this might go a long way to protecting children from skin cancer. Prevention is better than treatment.

Since nonmelanoma skin cancer is often handled surgically and not counted in cancer statistics, should people still be concerned?

Dr. Kraemer: No one likes to have cancer, period. Removal of cancer is not fun even if it is not life- threatening. Nonmelanoma cancers are closely related to sun exposure. There are really two kinds: one occurs in basal cells and the other in squamous cells.

Basal cell cancer virtually never spreads or metastasizes throughout the body, but it can be very locally invasive, especially in the face. It can invade and go into the brain. We have had patients that have died after it invaded through the eye, and it could not be treated. This is very rare, but it can happen. Squamous cell cancers also don’t metastasize that often, but they can spread anywhere.

Are older or younger people most affected by skin cancers?

Dr. Kraemer: Melanomas more often occur in younger people than do basal and squamous cell carcinomas. The average age of someone with basal cell and squamous cell is 50 years old.

What is xeroderma pigmentosum?

Dr. Kraemer: XP is a genetic condition characterized by a sensitivity to all sources of ultraviolet radiation. XP patients have an increased susceptibility to developing all kinds of skin cancers. Their chances of developing skin cancer is about 1,000 times the normal amount. We discovered that they have defective DNA repair genes. We found that XP can occur in all races-not just people you would generally think of as getting skin cancer.

How do these defective DNA repair genes relate to developing skin cancer?

Dr. Kraemer: Ultraviolet (UV) radiation penetrates the skin and damages the DNA. The DNA repair genes may repair the damaged cells, the damaged cells may die or, in other cases, the cells try to continue working and replicate the DNA, but because of the damage, there is a mutation introduced that can lead to cancers. So XP patients have a defect in their DNA repair system that leads to the 1,000-fold increase in skin cancer. We’ve been studying XP patients here at NIH, and we have found there are a number of different DNA repair genes that are responsible for this disorder. These findings mean that those genes are protecting the people who don’t have XP from getting skin cancers.

What are some of the promising areas of research in nonmelanoma skin cancer prevention?

Dr. DiGiovanna: Isotretinoin (Accutane), a derivative of vitamin A, has been studied as an agent to prevent cancers in patients at high risk, and it has been effective in studies of XP patients, who develop large numbers of skin cancers. T4N5 liposome lotion (Dimericine) has been shown to absorb into skin fairly well and, in one study, to prevent new skin cancers in XP patients. It is another approach to chemoprevention. Clinical trials using Celecoxib in patients with actinic keratoses, a precancerous condition, are also taking place.

Dr. Kraemer: Discovering the basic mechanism that creates skin cancer is the most important research; looking at it from initiation, promotion, precancer to cancer. We are learning about what is happening at each of those stages and want to try to find ways to interrupt the process and prevent cancer.

How successful have retinoids, such as isotretinoin, been in preventing skin cancer?

Dr. Kraemer: We did a study here a few years ago with Accutane, which was very effective in preventing skin cancer in patients with XP. One patient would get 20 separate primary skin cancers each year for many years, and she was just a teenager. We gave her the oral medicine. Within two years, she was getting two or three cancers a year – a really small number. Unfortunately, when we stopped the medicine, she started getting tumors again, and the medicine itself caused a number of side effects. It made the skin very sensitive to sunlight. It causes birth defects, so people on it can’t get pregnant. Also, it causes calcifications of tendons and ligaments. Accutane is on the market for acne treatment. The people who are treated for acne are treated for just a short time, but patients with XP would have to be treated for a long time. There are thousands of retinoids, and we hope that someday we can find a different retinoid that is equally as effective but less toxic.

How does the TN45 liposome lotion work to repair DNA damaged skin and prevent skin cancers?

Dr. Kraemer: We’ve been following that fairly closely. The cream has an enzyme that comes from bacteria that will repair most of the damage done to DNA. The enzyme uses a different method of attacking the damage than the human DNA repair system does. Nevertheless, a study of patients who have XP was done, and the cream reduced the frequency of precancerous lesions and also of skin cancer. I think it’s the beginning of an interesting approach of putting proteins into the cells to see if we can alter their repair characteristics.

This is different from gene therapy which involves putting DNA back. This is like giving someone with diabetes a shot of insulin, but instead, we are giving patients the protein they are missing. So, it’s an interesting approach, and we’ve been discussing it with the company that made it. However, this treatment has not been approved by the Food and Drug Administration yet because further study needs to be done. Yet, it is very intriguing.

How can this research benefit the general public in the future?

Dr. Kraemer: Certainly these genetic approaches might identify people who might be at greater risk. DNA repair genes are exceedingly important in protecting against skin cancer. The average age of skin cancer in the general population is 60, but in the XP patients it is 10 years. This means there is a 50-year difference between the average age of onset of skin cancer between XP patients and the general population. If your DNA repair system is working, you get 50 more years of sun exposure before you get your first skin cancer. So, these genes are very important in protection against skin cancer.

Another study we are doing is where we found what are called polymorphisms in these DNA repair genes. Polymorphisms are normal variations in the sequence of genes. These are much more common in the general population. XP itself occurs in maybe one in a million people and the carriers are about 1 in 500. We did one study collaborating with M. D. Anderson Cancer Center in Texas where we had found one repair gene polymorphism occurs in 40 percent of the population. We found that people who have this variation have an increased susceptibility to squamous cell cancer of the head and neck compared to the people who don’t.

Are sunscreens really effective in preventing skin cancer?

Dr. DiGiovanna: There is evidence that sunscreens can protect against the development of malignancy both in animal models and in people. Studies have shown that UV radiation can induce tumors in animals and that sunscreen can prevent it.

Dr. Kraemer: Sun protection is more than sunscreens. Sun protection includes avoiding the sun, using clothing to protect yourself, getting shade under a tree if you are going outside, and wearing hats.

It is important for people to understand sun protection factors. The sun protection factor multiplies the number of minutes you can be outside before you burn. For example, if someone can be outside for 10 minutes before they burn, and they use a sunblock with a factor of 10, they can go 100 minutes. The amount of protection begins to level off at 15. What a lot of people do not realize is that although the higher factors do give more protection, it is not as big difference as between 0 to 15. We recommend use of a sunblock of at least SPF (Sun Protection Factor) 15.

Besides sunblock, how else can people protect themselves from skin cancer?

Dr. Kraemer: There is a shadow rule of sun protection. It’s called “short shadow seek shade.” The reason is that when your shadow is short, the sun is above your head, and you have to protect yourself. As the sun goes down, it goes through more and more of the atmosphere and your shadow gets longer. Eventually the atmosphere itself blocks some of the UV radiation-so it is kind of like a sunblock itself. Meteorologist Leith Holloway made measurements and came up with this shadow rule. It turns out that when your shadow is equal to your height, the SPF of the atmosphere is between 2 and 3 and when the sun goes down even more your shadow will get longer, and you don’t need to protect yourself as much. The time you have to protect yourself is when your shadow is shorter than you are. This rule is very important because you don’t even need to know how to tell time. Even kindergarteners can know when their shadow is shorter than they are. It works independently of daylight savings time and does not matter what time zone you are in or if it is summer or winter. In fact, it automatically adjusts for that. In the winter, the sun never gets that high. It is an important and very simple way of knowing what to do.

What about vitamin D levels? Don’t people need to be in the sun?

Dr. Kraemer: We did a study with XP patients that were protected from sun exposure. All had vitamin D levels in good ranges. Even with sun protection, it is possible to have normal vitamin D levels with a good diet and exercise.

Could certain foods be related to preventing skin cancer?

Dr. DiGiovanna: There has been some research done to study the effect of compounds that work against oxidative damage. These antioxidants may be helpful in preventing damage. There is much work ongoing; green tea is one antioxidant that is being studied to see if it can prevent damage.

What is being done in the area of nonmelanoma skin cancer treatment?

Dr. DiGiovanna: The primary treatment for most nonmelanoma skin cancers is destructive: either surgery or some other destructive method that removes the tumor. There are some topical solutions that can be useful, including a new topical treatment, imiquimod. It is being used in studies with precancerous conditions and skin cancers to stimulate the immune system. It increases the levels of interferon in the body at the site of application. It is not FDA approved yet, but it has been associated with the clearing of nonmelanoma skin cancer.

The National Cancer Institute (NCI) is a component of the National Institutes of Health (NIH), one of eight agencies that compose the Public Health Service (PHS) in the Department of Health and Human Services (DHHS). The NCI, established under the National Cancer Act of 1937, is the Federal Government’s principal agency for cancer research and training.

article syndicated from NCI

updated about 1 year ago

There are several types of skin cancer. The most common forms of skin cancer are basal cell carcinoma followed by squamous cell carcinoma. These forms are often referred to as nonmelanoma skin cancer to differentiate them from a third type, melanoma, which is less common, more deadly, and more likely to spread throughout the body.

Basal Cell Carcinoma and Squamous Cell Carcinoma

It is estimated that nonmelanoma skin cancer is on the rise and that 1 million cases will occur each year. Exact numbers of nonmelanoma skin cancer cases are not readily available because most are treated in doctors’ offices and may not be reported to cancer registries. Researchers estimate that 40 to 50 percent of people in the United States who live to age 65 will have nonmelanoma skin cancer at least once. The risk is highest for fair-skinned people with red or blond hair and light-colored eyes.

Ninety percent of all skin cancers in the United States are basal cell carcinoma. This type of cancer grows slowly and rarely spreads to other areas. It is typically found on the head, face, neck, hands, and arms but can occur anywhere. Squamous cell carcinoma also rarely spreads but is more likely to do so than basal cell carcinoma. Despite a fatality rate of less than one percent, these cancers should be treated because they can invade and destroy nearby tissue.

The main cause of nonmelanoma skin cancer is ultraviolet (UV) radiation from the sun or artificial sources such as sunlamps or tanning booths. An individual’s risk appears to involve geographic location. People who in live in areas with higher levels of UV radiation from the sun, such as those living closer to the equator, have higher risk. Lifetime exposure to UV radiation is also a risk factor. Damage can occur early in life, but most skin cancers appear after age 50 as a result of cumulative UV exposure.

The appearance of skin cancer is not always the same. It may be a small, smooth, shiny, pale, or waxy lump or a firm red lump. Some people develop a precancerous condition called actinic keratosis, a rough, red or brown scaly patch on the skin that may develop into squamous cell carcinoma. It usually occurs in areas that have been exposed to the sun, such as the face, the back of the hands, and the lower lip.

By conducting a monthly skin self-exam, people may notice a new area on the skin that may be suspicious and should consult a doctor. In addition, a doctor may notice a possible skin cancer or precancerous lesion during a routine examination. However, not all suspicious moles or skin conditions are skin cancer. Skin cancers can be diagnosed with a biopsy, in which the lesion is removed and examined by a pathologist. If the cancer has not spread, no further treatment may be necessary.

The primary way to prevent skin cancer is for people to reduce exposure to UV radiation. This involves avoiding the midday sun and artificial UV sources such as tanning beds, wearing protective clothing such as hats and sunglasses, and using sunscreens. Researchers have found that sunscreens are effective in protecting people from DNA damage in the skin due to UV exposure1. Daily sunscreen use reduces the incidence of actinic keratosis2. Clinical evidence suggests it is better to use sunscreens with both UVA and UVB protection than those with UVB alone. UVB rays are more likely than UVA rays to cause sunburn, but UVA rays pass more deeply into the skin. Sunscreen effectiveness may depend upon using it as directed, which includes liberal application and reapplication after water exposure or excessive perspiration. Sunscreens should be used in conjunction with other methods of avoiding UV exposure as mentioned above.

Certain clothing is made from sun-protective fabrics, which are usually darker and have a tighter weave than other fabrics. Sun-protective clothing is labeled with an Ultraviolet Protection Factor from 15 to 50, depending upon how much UV radiation passes through the fabric. The Federal Trade Commission has further information regarding these products.

Researchers are studying individuals who have an increased risk of skin cancers to find new ways to prevent and detect the development of skin cancer.

Most treatments for skin cancer currently involve some kind of surgery. Often skin cancer is removed completely during biopsy with no further treatment required. Most nonmelanoma skin cancers are curable, but people who have had skin cancer have a higher than average risk of developing another skin cancer.

Melanoma

Melanoma is a disease of pigment cells, or melanocytes, and typically occurs in the skin. Melanoma also occurs infrequently in the eyes, digestive tract, lymph nodes, or other areas where there are melanocytes. It is one of the most commonly occurring invasive cancers, affecting people of all ages, and incidence rates are increasing.

The rate of new melanoma cases increased from 1973 to 1998, although the rate of increase has slowed since 19813. According to the most recent data from the Surveillence, Epidemiology and End Results (SEER) program, NCI’s authoritative source of information on cancer incidence and survival in the United States, for every 100,000 people in the United States, there are 17.7 new cases of melanoma each year. Incidence is higher for men than for women overall, but young women have higher rates than young men. The overall incidence rate for men is 22.5 per 100,000 men compared with 14.4 per 100,000 for women. The death rate is 2.7 per 100,000. Five years after diagnosis, 89.6 percent survive either in remission, disease-free, or under treatment. Women have a 1.25 percent lifetime risk of being diagnosed while men have a lifetime risk of 1.77 percent.

Melanoma sometimes appears as a change in an existing mole or as a new mole. It comes in a variety of shapes and colors. Regular skin self-exams help people recognize what their moles look like so they can notice changes. Melanoma may develop on any skin surface. For men, the most common areas are the trunk, and to a lesser extent the head and neck. For women, the most common area is the lower legs followed by the trunk. Melanoma is rare in people with dark skin, but they may develop it under fingernails or toenails, or on palms or soles of the feet where the skin is lighter. Melanoma may also spread throughout the lymph nodes to other parts of the body.

People can use the ABCD (Asymmetry, Border, Color, Diameter) method when looking for mole characteristics that may indicate melanoma:

• Asymmetry - The shape of one half does not match the other.
• Border - The edges are ragged, notched, blurred, or irregular in outline or the pigment may spread into the surrounding skin.
• Color - Uneven color with shades of black, brown, and tan or areas of white, gray, red, pink, or blue may be visible. Occasionally, melanoma can be the same color as the rest of the skin.
• Diameter - There is a change in size. Melanomas are usually larger than the eraser of a pencil, but may be smaller.

Since melanoma moles do not all look the same, if you see anything suspicious, you should have a doctor examine it. The only way to definitively diagnose melanoma is with a biopsy, which involves a doctor removing all or part of the growth so that a pathologist might examine it for cancer cells.

The exact causes of melanoma are unknown. However, risk factors include having atypical moles known as dysplastic nevi; many moles; fair skin; personal history of melanoma or other skin cancer; family history of melanoma; weakened immune system; experiencing severe blistering sunburns; and exposure to UV radiation. The disease is more common in people who live in areas that get large amounts of UV radiation from the sun, such as people living near the equator. UV radiation from artificial sources such as sunlamps and tanning booths can also damage the skin and increase melanoma risk.

To prevent melanoma, people, particularly children and young adults, are often urged to follow the same precautions as those used to prevent nonmelanoma skin cancer, such as avoiding UV exposure and wearing protective clothing and sunscreen.

Melanoma treatments depend on the stage of the cancer at diagnosis. Melanoma can be cured if it is diagnosed and treated when the tumor is thin and has not deeply invaded the skin. When a melanoma becomes thick and deep, the disease often spreads to other parts of the body and is difficult to control. The most common treatment for melanoma is surgery to remove the tumor, which is most successful for people in early stages. Chemotherapy drugs are also sometimes used to kill the cancer cells, as is immunotherapy, which uses cytokines, a component of the body’s own immune system, to fight the cancer. Patients with metastatic melanoma, where the melanoma has spread to other organs, may be treated with interferon alpha and interleukin-2 (IL-2), which stimulates the growth and activity of immune cells that can destroy cancer cells. Clinical trials of new experimental treatments for people with advanced stages of melanoma are currently being conducted. These include work with therapeutic melanoma vaccines designed to help the immune system recognize and attack the cancer cells without harming normal cells. More information about clinical trials using experimental melanoma treatments can be found at http://www.clinicaltrials.gov.

Cited Resources

1. Ananthaswamy, H N. et al. Inhibition of Solar Simulator-Induced p53 Mutations and Protection Against Skin Cancer Development in Mice by Sunscreens. Journal of Investigative Dermatology 112:763-768, 1999.
2. Darlington, S, et al. A Randomized Controlled Trial of assess Sunscreen Application and Beta Carotene Supplementaiton in the Prevention of Solar Keratoses. Archives of Dermatology. 139: 451-455, 2003.
3. National Cancer Institute. 2001 Cancer Progress Report. http://progressreport.cancer.gov/

Additional Resources

Scotto, J. Risk Factors: Skin (Nonmelanoma). Biostatistics Branch. National Cancer Institute.

http://www.cancer.gov.

Federal Trade Commission. Sun-Protective Clothing: Wear It Well.
http://www.ftc.gov. May 2001

http://www.ftc.gov/bcp/conline/pubs/alerts/sunalrt.htm

National Cancer Institute. What You Need to Know About Melanoma.
http://www.cancer.gov/cancerinfo/wyntk/melanoma. Updated 3/31/2003.

National Cancer Institute. What You Need to Know About Skin Cancer.
http://www.cancer.gov/cancerinfo/wyntk/skin. Updated 9/16/2002.

NCI Resources on Skin Cancer

http://cancer.gov/cancerinfo/skin-cancer-awareness

NCI Resources on Melanoma

http://cancer.gov/cancerinfo/types/melanoma

The National Cancer Institute (NCI) is a component of the National Institutes of Health (NIH), one of eight agencies that compose the Public Health Service (PHS) in the Department of Health and Human Services (DHHS). The NCI, established under the National Cancer Act of 1937, is the Federal Government’s principal agency for cancer research and training.

article syndicated from NCI

updated about 1 year ago

Skin cancer is a disease in which malignant (cancer) cells form in the tissues of the skin.

The skin is the body’s largest organ. It protects against heat, sunlight, injury, and infection. Skin also helps control body temperature and stores water, fat, and vitamin D. The skin has several layers, but the two main layers are the epidermis (upper or outer layer) and the dermis (lower or inner layer). Skin cancer begins in the epidermis, which is made up of 3 kinds of cells:

• Squamous cells: Thin, flat cells that form the top layer of the epidermis.
• Basal cells: Round cells under the squamous cells.
• Melanocytes: Found in the lower part of the epidermis, these cells make melanin, the pigment that gives skin its natural color. When skin is exposed to the sun, melanocytes make more pigment, causing the skin to tan, or darken.

Skin cancer can occur anywhere on the body, but it is most common in skin that has been exposed to sunlight, such as the face, neck, hands, and arms. There are several types of cancer that start in the skin. The most common types are basal cell carcinoma and squamous cell carcinoma, which are nonmelanoma skin cancers. Actinic keratosis is a skin condition that sometimes develops into squamous cell carcinoma.

This summary refers to the treatment of nonmelanoma skin cancer and actinic keratosis. Nonmelanoma skin cancers rarely spread to other parts of the body. Melanoma, the rarest form of skin cancer, is more likely to invade nearby tissues and spread to other parts of the body. Refer to the following PDQ summaries for information on melanoma and other kinds of skin cancer:

• Melanoma Treatment
• Mycosis Fungoides and the S?zary Syndrome Treatment
• Kaposi’s Sarcoma Treatment

Skin color and exposure to sunlight can affect the risk of developing nonmelanoma skin cancer and actinic keratosis.

Risk factors for basal cell carcinoma and squamous cell carcinoma include the following:

• Being exposed to a lot of natural or artificial sunlight.
• Having a fair complexion (blond or red hair, fair skin, green or blue eyes, history offreckling).
• Having scars or burns on the skin.
• Being exposed to arsenic.
• Having chronic skin inflammation or skin ulcers.
• Being treated with radiation.
• Taking immunosuppressive drugs (for example, after an organ transplant).
• Having actinic keratosis.

Risk factors for actinic keratosis include the following:

• Being exposed to a lot of sunlight.
• Having a fair complexion (blond or red hair, fair skin, green or blue eyes, history of freckling).

Nonmelanoma skin cancer and actinic keratosis often appear as a change in the skin.

Not all changes in the skin are a sign of nonmelanoma skin cancer or actinic keratosis, but a doctor should be consulted if changes in the skin are seen.

Possible signs of nonmelanoma skin cancer include the following:

• A sore that does not heal.
• Areas of the skin that are:
  • Small, raised, smooth, shiny, and waxy.
  • Small, raised, and red or reddish-brown.
  • Flat, rough, red or brown, and scaly.
  • Scaly, bleeding, or crusty.
  • Similar to a scar and firm.

Possible signs of actinic keratosis include the following:

• A rough, red, pink, or brown, raised, scaly patch on the skin.
• Cracking or peeling of the lower lip that is not helped by lip balm or petroleum jelly.

Tests or procedures that examine the skin are used to detect (find) and diagnose nonmelanoma skin cancer and actinic keratosis.

The following procedures may be used:

• Skin examination: A doctor or nurse checks the skin for bumps or spots that look abnormal in color, size, shape, or texture.
• Biopsy: All or part of the abnormal-looking growth is cut from the skin and viewed under a microscope to see if cancer cells are present. There are 3 main types of skin biopsies:
  • Shave biopsy: A sterile razor blade is used to “shave off” the abnormal-looking growth.
  • Punch biopsy: A special instrument called a punch or a trephine is used to remove a circle of tissue from the abnormal-looking growth.
  • Excisional biopsy: A scalpel is used to remove the entire growth.

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis (chance of recovery) depends mostly on the stage of the cancer and the type of treatment used to remove the cancer.

Treatment options depend on the following:

• The stage of the cancer (whether it has spread deeper into the skin or to other places in the body).
• The type of cancer.
• The size and location of the tumor.
• The patient’s general health

Health Professional Version

Nonmelanoma skin cancer

Evidence suggests that reduction of exposure to ultraviolet (UV) radiation will reduce the incidence of nonmelanoma skin cancer. Sun exposure can be reduced by changing patterns of outdoor activities to reduce time of exposure to high-intensity UV radiation, and by using adequate amounts of sufficiently protective sunscreens or wearing protective clothing when exposed to sunlight.[1]

Levels of Evidence

1b: Evidence obtained from at least one well-designed and conducted randomized controlled trial with a generally accepted intermediate endpoint.

3aii: Evidence obtained from well-designed and conducted cohort or case-control analytic studies, preferably from more than one center or research group, with a cancer incidence endpoint.

5: Opinions of respected authorities based on clinical experience or reports of expert committees.

Cutaneous melanoma

Evidence suggests that avoidance of sunburns, especially in childhood and adolescence, may reduce the incidence of cutaneous melanoma. Sunburn can be avoided by changing patterns of outdoor activities to reduce time of exposure to high-intensity UV radiation, by wearing protective clothing when exposed to sunlight, and by using adequate amounts of sufficiently protective sunscreen. Sunscreen is not a substitute for avoidance of sun exposure.[1,2]

Levels of Evidence

3aii: Evidence obtained from well-designed and conducted cohort or case-control analytic studies, preferably from more than one center or research group, with a cancer incidence endpoint.

4aii: Ecologic (descriptive) studies with a cancer incidence endpoint.

5: Opinions of respected authorities based on clinical experience or reports of expert committees.

References

1. Vainio H, Miller AB, Bianchini F: An international evaluation of the cancer-preventive potential of sunscreens. Int J Cancer 88 (5): 838-42, 2000. [PUBMED Abstract]

2. Autier P, Dor? JF, Cattaruzza MS, et al.: Sunscreen use, wearing clothes, and number of nevi in 6- to 7-year-old European children. European Organization for Research and Treatment of Cancer Melanoma Cooperative Group. J Natl Cancer Inst 90 (24): 1873-80, 1998.

The National Cancer Institute (NCI) is a component of the National Institutes of Health (NIH), one of eight agencies that compose the Public Health Service (PHS) in the Department of Health and Human Services (DHHS). The NCI, established under the National Cancer Act of 1937, is the Federal Government’s principal agency for cancer research and training.

article syndicated from NCI

updated about 1 year ago

Researchers have shown for the first time that individual risk of melanoma, the most serious form of skin cancer, is associated with the intensity of sunlight that a person receives over a lifetime. Published in the journal Cancer Research*, the study also indicates that the risk of melanoma for non-Hispanic whites increases with increased time outdoors – even for men and women who can develop a deep tan.

Scientists have long recognized that rates of melanoma are higher in areas that are closer to the equator or receive more sunlight, and that ultraviolet-B rays are the primary cause of sunburn and skin cancer. In this study, the authors developed a novel approach to measure an individual’s sun exposure over a lifetime, taking into account where an individual has lived throughout his or her life. This information determines average annual UVB intensity – the average amount of ultraviolet-B rays that a person could be exposed to per year over his or her lifetime. The data led the researchers to conclude that a 10 percent increase in the average annual intensity was associated with a 19 percent increase in the individual’s risk for melanoma in men and a 16 percent increase in women, at any age.

“We’re learning more about the kinds of exposures that cause melanoma,” said Thomas Fears, Ph.D., the first author of the paper and a scientist at the National Cancer Institute in Bethesda, Md. “The risk of melanoma is greatest for people who develop little or no tan. However, we’ve learned that where people live as both kids and adults and how much UVB shines in those places are important factors – regardless of tanning ability.”

According to Fears, it is not unusual to see at least a 10 percent difference in intensity between two locations. New Orleans, for example, receives 20 percent more UVB each year than Atlanta.

In addition to estimating individual risk, the authors analyzed the number of hours that study participants spent outdoors. They found that the number of summer hours spent outside prior to age 20 was much larger than after age 20. In light of this distinction, the researchers hypothesized that differences in melanoma risk previously attributed to the “critical period” of childhood may, in fact, be due to the larger number of hours that children typically spend outdoors compared to adults.

“Studies such as this one serve as a reminder of the importance for adults and children alike to develop good, lifelong habits for protecting themselves from skin-damaging sun exposure,” said Health and Human Services Secretary Tommy G. Thompson. “We are now seeing that not only length of sun exposure, but also the intensity of the sun’s rays can affect one’s risk of melanoma.”

This study included 718 melanoma patients recruited from the Hospital of the University of Pennsylvania, in Philadelphia, and from the University of California in San Francisco. The comparison group included 945 non-melanoma patients from those areas. The researchers limited the analysis to non-Hispanic whites because the numbers of cases in other racial/ethnic groups were too few for analysis.

Each participant was interviewed in person to gather data including tendency to sunburn and ability to tan, along with medical, occupational, residential and outdoor exposure histories. Residential histories were constructed in six-month intervals, from date of birth to date of interview. Robertson-Berger (RB) meters, which measure the amount of solar radiation received in a particular location, were used to estimate the UVB intensity. A person’s cumulative intensity was estimated by adding up the RB counts for each residence location in six-month increments. Average annual intensity was determined by dividing the cumulative intensity by the person’s age in years.

Future analyses will examine the effects of intermittent exposures on individual melanoma risk. For example, researchers will consider whether people who remain indoors for much of the week and then spend large amounts of time outdoors over the weekend or during a vacation are at higher risk of melanoma.

An estimated 53,600 people will be diagnosed with melanoma in the United States in 2002, and an estimated 7,400 people will die of the disease. Melanoma can be cured if detected and treated early.

The National Cancer Institute (NCI) is a component of the National Institutes of Health (NIH), one of eight agencies that compose the Public Health Service (PHS) in the Department of Health and Human Services (DHHS). The NCI, established under the National Cancer Act of 1937, is the Federal Government’s principal agency for cancer research and training.

article syndicated from NCI

updated about 1 year ago

Melanoma is a disease in which malignant (cancer) cells form in the skin cells called melanocytes (cells that color the skin).

Melanocytes are found throughout the lower part of the epidermis. They produce melanin, the pigment that gives skin its natural color. When skin is exposed to the sun, melanocytes produce more pigment, causing the skin to tan, or darken.

The skin is the body’s largest organ. It protects against heat, sunlight, injury, and infection. The skin has 2 main layers: the epidermis (upper or outer layer) and the dermis (lower or inner layer).

When melanoma starts in the skin, the disease is called cutaneous melanoma. This PDQ summary is about cutaneous (skin) melanoma. Melanoma may also occur in the eye and is called intraocular or ocular melanoma. (Refer to the PDQ summary on Intraocular (Eye) Melanoma Treatment for more information.)

There are 3 types of skin cancer:

• Melanoma.
• Basal cell skin cancer.
• Squamous cell skin cancer.

Melanoma is more aggressive than basal cell skin cancer or squamous cell skin cancer. (Refer to the PDQ summary on Skin Cancer Treatment for more information on basal cell and squamous cell skin cancer.)

Melanoma can occur anywhere on the body.

In men, melanoma is often found on the trunk (the area from the shoulders to the hips) or the head and neck. In women, melanoma often develops on the arms and legs. Melanoma usually occurs in adults, but it is sometimes found in children and adolescents.

Unusual moles, exposure to sunlight, and health history can affect the risk of developing melanoma.

Risk factors include the following:

• Unusual moles.
• Exposure to natural sunlight, including sunburns during childhood.
• Exposure to artificial ultraviolet light (tanning booth).
• Family or personal history of melanoma.
• Red or blond hair.
• White or light-colored skin and freckles.
• Blue eyes.

Possible signs of melanoma include a change in the appearance of a mole or pigmented area.

These and other symptoms may be caused by melanoma or by other conditions. A doctor should be consulted if any of the following problems occur:

• A mole that:
  • changes in size, shape, or color.
  • has irregular edges or borders.
  • is more than 1 color.
  • is asymmetrical (if the mole is divided in half, the 2 halves are different in size or shape).
  • itches.
  • oozes, bleeds, or is ulcerated (a hole forms in the skin when the top layer of cells breaks down and the underlying tissue shows through).
• Change in pigmented (colored) skin.
• Satellite moles (new moles that grow near an existing mole).

Tests that examine the skin are used to detect (find) and diagnose melanoma.

If a mole or pigmented area of the skin changes or looks abnormal, the following tests and procedures can help detect and diagnose melanoma:

Skin examination: A doctor or nurse examines the skin to look for moles, birthmarks, or other pigmented areas that look abnormal in color, size, shape, or texture.

Biopsy: A local excision is done to remove as much of the suspicious mole or lesion as possible. A pathologist then looks at the tissue under a microscope to check for cancer cells. Because melanoma can be hard to diagnose, patients should consider having their biopsy sample checked by a second pathologist.

Suspicious areas should not be shaved off or cauterized (destroyed with a hot instrument, an electrical current, or a caustic substance).

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis (chance of recovery) and treatment options depend on the following:

• The stage of melanoma (whether cancer is found in the outer layer of skin only, or has spread to the lymph nodes or to other places in the body).
• Whether there was bleeding or ulceration at the primary site.
• The location and size of the tumor.
• The patient’s general health.

Although many people are successfully treated, melanoma can recur (come back)

Health Professional Version

Melanoma is a malignant tumor of melanocytes, cells that are derived from the neural crest. Although most melanomas arise in the skin, they may also arise from mucosal surfaces or at other sites to which neural crest cells migrate. Melanoma occurs predominantly in adults, and more than half of the cases arise in apparently normal areas of the skin. Early signs in a nevus that would suggest malignant change include darker or variable discoloration, itching, an increase in size, or the development of satellites. Ulceration or bleeding are later signs. Melanoma in women occurs more commonly on the extremities and in men on the trunk or head and neck, but it can arise from any site on the skin surface. A biopsy, preferably by local excision, should be performed for any suspicious lesions, and the specimens should be examined by an experienced pathologist to allow for microstaging. Suspicious lesions should never be “shaved off” or cauterized. Studies show that distinguishing between benign pigmented lesions and early melanomas can be difficult, and even experienced dermatopathologists can have differing opinions. To reduce the possibility of misdiagnosis for an individual patient, a second review by an independent qualified pathologist should be considered.[1]

Prognosis is affected by clinical and histological factors and by anatomic location of the lesion. Thickness and/or level of invasion of the melanoma, mitotic index, presence of tumor infiltrating lymphocytes, number of regional lymph nodes involved, and ulceration or bleeding at the primary site affect the prognosis.[2-5] Microscopic satellites in stage I melanoma may be a poor prognostic histologic factor, but this is controversial.[6] Patients who are younger, female, and who have melanomas on the extremities generally have a better prognosis.[2-5]

Clinical staging is based on whether the tumor has spread to regional lymph nodes or distant sites. For disease clinically confined to the primary site, the greater the thickness and depth of local invasion of the melanoma, the higher the chance of lymph node or systemic metastases and the worse the prognosis. Melanoma can spread by local extension (through lymphatics) and/or by hematogenous routes to distant sites. Any organ may be involved by metastases, but lungs and liver are common sites. The risk of relapse decreases substantially over time, although late relapses are not uncommon.[7,8]

References

1. Corona R, Mele A, Amini M, et al.: Interobserver variability on the histopathologic diagnosis of cutaneous melanoma and other pigmented skin lesions. J Clin Oncol 14 (4): 1218-23, 1996. [PUBMED Abstract]
2. Balch CM, Soong S, Ross MI, et al.: Long-term results of a multi-institutional randomized trial comparing prognostic factors and surgical results for intermediate thickness melanomas (1.0 to 4.0 mm). Intergroup Melanoma Surgical Trial. Ann Surg Oncol 7 (2): 87-97, 2000. [PUBMED Abstract]
3. Manola J, Atkins M, Ibrahim J, et al.: Prognostic factors in metastatic melanoma: a pooled analysis of Eastern Cooperative Oncology Group trials. J Clin Oncol 18 (22): 3782-93, 2000. [PUBMED Abstract]
4. Balch CM, Buzaid AC, Soong SJ, et al.: Final version of the American Joint Committee on Cancer staging system for cutaneous melanoma. J Clin Oncol 19 (16): 3635-48, 2001. [PUBMED Abstract]
5. Lotze MT: Melanoma. In: DeVita VT Jr, Hellman S, Rosenberg SA, eds.: Cancer: Principles and Practice of Oncology. 6th ed. Philadelphia, Pa: Lippincott Williams & Wilkins, 2001, pp. 2022-2028.
6. Le?n P, Daly JM, Synnestvedt M, et al.: The prognostic implications of microscopic satellites in patients with clinical stage I melanoma. Arch Surg 126 (12): 1461-8, 1991. [PUBMED Abstract]
7. Shen P, Guenther JM, Wanek LA, et al.: Can elective lymph node dissection decrease the frequency and mortality rate of late melanoma recurrences? Ann Surg Oncol 7 (2): 114-9, 2000. [PUBMED Abstract]
8. Tsao H, Cosimi AB, Sober AJ: Ultra-late recurrence (15 years or longer) of cutaneous melanoma. Cancer 79 (12): 2361-70, 1997. [PUBMED Abstract]

The National Cancer Institute (NCI) is a component of the National Institutes of Health (NIH), one of eight agencies that compose the Public Health Service (PHS) in the Department of Health and Human Services (DHHS). The NCI, established under the National Cancer Act of 1937, is the Federal Government’s principal agency for cancer research and training.