Skin Cancer - Melanoma

Introduction

Melanoma is the deadliest form of skin cancer.  It occurs when the melanocytes in the skin grow abnormally and out of control.  Exposure to ultraviolet (UV) rays from the sun and a history of childhood sunburns contribute to the development of melanoma.  Researchers are finding that some people may inherit genes that lead to melanoma formation.

Melanomas that are small, shallow, detected early, and treated early have very good cure rates.  Untreated melanomas are very aggressive and fast growing.  The cancer can quickly spread throughout the body resulting in life threatening complications and death.

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Anatomy

Your skin covers your body and protects it from the environment.  Your skin is composed of three major layers, the epidermis, dermis, and subcutaneous tissue.  The epidermis is the outermost layer of your skin.  It protects your inner skin layers.  The epidermis is made up of protein containing cells called keratinocytes, also referred to as squamous cells.  The keratinocytes form at the bottom layer of the epidermis and move upward to the outer layer.  They eventually wear off and are replaced by the next layer of cells.  The epidermis also contains melanocytes.  This type of cell contains color pigments called melanin.  The lowest layer of the epidermis is composed of basal cells.
 
The dermis is your second layer of skin.  It is made up of connective tissue and provides structure.  It is composed of collagen and various elements that give your skin strength and elasticity.  The dermis contains hair cells, sweat glands, and sebaceous glands that secrete oils to hydrate the skin.
 
Subcutaneous tissue composes your inner most layer of skin.  Subcutaneous tissue contains fat cells.  The fat cells insulate your body and make your skin appear plump and full.  Below the subcutaneous tissue are fat tissues, your muscles, and bones.
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Causes

Melanoma results when the melanocytes in the epidermis of the skin or colored part of the eye grow abnormally and out of control, instead of dividing in an orderly manner.  Melanoma is a fast growing aggressive type of skin cancer that is very dangerous.  The cancer cells can quickly spread through the skin and travel in the blood vessels and lymphatic system.  This can lead to cancer elsewhere in the body and life-threatening illness.  Melanoma is the deadliest form of skin cancer.
 
Melanoma may develop on skin, a mole, or in the colored portions (iris) or retina of the eye.  Researchers are not sure exactly how all cases of melanoma develop, but it is associated with the amount of exposure to UV rays from the sun or artificial sunlight.  Some people have risk factors that increase their odds for developing melanoma.
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Symptoms

Melanoma can develop on the skin, in a mole, or in the iris or retina of the eye.  You should look for changes in the shape, size, or color of a mole.  Cancerous moles or skin areas may also develop pain, swelling, itching, and bleeding.  Melanoma can develop anywhere on the skin, even in places that have not been exposed to the sun.  However, the backs of men and the lower legs of women are the most frequent places that melanoma develops.
 
The ABCD method is useful when examining your skin for melanoma related changes:
A-  Asymmetry: One half of the abnormal area does not match the other half.
B-  Border Irregularity: The growth or mole has uneven, notched, ragged, or irregular edges.
C-  Color: The abnormal area or mole contains different colors instead of one solid color. 
There may be different shades of tan, brown, black, red, blue, or white.
D-  Diameter: The mole or abnormal growth is larger than ¼ inch across.  However, some melanomas may be smaller.
 
Actinic keratosis is a precancerous condition that can turn into melanoma.  It results from overexposure to the sun.  Actinic keratosis looks like small rough dry patches on the skin.  They may be pink-red or skin colored.  They typically appear in areas that have been exposed to the sun.  Actinic keratosis is a slow growing condition.  They may go away on their own and come back.  Your doctor should remove actinic keratosis.
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Diagnosis

You should contact your doctor if you notice a change in the color, texture, or appearance of your skin or a mole and if you have a sore that does not heal.  Your doctor will let you know how often you should have a professional skin examination.  Your eye doctor should check your irises and the retinas of your eyes during your eye exams. 
 
Your doctor can diagnose melanoma by examining the growth and performing a biopsy of the suspected area.  A biopsy is a simple procedure that takes tissue for examination.  There are a few types of biopsy methods. 
 
After numbing your skin, your doctor may perform a shave, punch, incisional, or excisional biopsy.  A shave biopsy removes the top layers of the skin.  A punch biopsy uses a round punch to cut through all of the layers of skin to remove a tissue plug.  An incisional biopsy removes a part of the tumor, and an excisional biopsy removes the entire tumor.  In some cases, the incisions will be stitched. 
 
The tissue samples are sent to a laboratory for examination. Request to have your tissue sample examined by a dermapathologist.  A dermapathologist is a pathologist with special training in skin cell disorders.  The dermapathologist will determine if your tissue sample contains melanoma.
 
Your doctor’s office will call you with the results when they receive them.  Skin cancer is classified based on how far it has spread.  Stages are classified as 0-4, with 4 being a more serious cancer.  There is more than one type of staging system, so make sure that you and your doctor are referring to the same one.
 
Melanoma is a fast growing type of skin cancer and it can spread very quickly.  Melanoma usually starts on the skin’s surface, but can quickly develop roots that grow through the other skin layers and fatty tissues.  The cancer cells can enter the bloodstream and lymphatic system.  This can cause the cancer to spread to other parts of the body.  Melanoma tends to spread to the lymph nodes, lungs, and brain.  Your doctor will order tests if metastasized (spreading) cancer is suspected
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Treatment

Melanomas that are small, shallow, detected early, and treated early have very good cure rates with surgery.  The goal of treatment is to remove all of the cancer cells.  There are several types of removal methods.  The treatment that you receive depends on the size, location, and stage of your cancer.
 
A simple excision is a method that cuts out the tumor and a radius of healthy cells around it.  The incision is stitched back together.  A specialized technique, Mohs micrographically controlled surgery, is used to treat large skin cancers or skin cancers that have come back.  For Mohs surgery, the doctor removes a layer of skin containing the cancerous melanoma cells and examines it under a microscope right away.  The process is repeated until the skin samples are found to be free of cancer cells.  The advantages of Mohs surgery are that only the minimum amount of tissue necessary is removed and the specimens are carefully examined.  Mohs surgery is associated with high cure rates.
 
Skin grafting and reconstructive surgery may be necessary after the removal of large melanomas.  Scarring after skin cancer removal is common.  Cosmetic surgery techniques can improve the appearance of scars after the initial surgery.  Some people choose to cover their scars with make-up.
 
If your cancer has spread, surgery, radiation, chemotherapy, and immunotherapy treatments may be necessary to treat the metastasized cancer or relieve symptoms.  The deeper the melanoma, the greater the risk that it will return.  The five year survival rates are the best for small superficial melanomas with early detection and treatment.
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Surgery

Melanoma is the most dangerous type of skin cancer.  It can be very aggressive and grow quickly.  Melanoma can metastasize to the blood vessels and lymphatic system.  From there, it can easily spread throughout the body.  Melanoma can spread to the bones and vital organs, such as the liver, GI tract, lungs, and brain.  Melanoma can be difficult to treat once it has spread, and it can cause death.
 
Melanoma that has been removed can come back, even up to about 10 years later.  The risk of recurrence is associated with the depth of the cancer.  Deeper cancers have a greater risk of coming back.  Because the potential consequences are so severe, you should be vigilant about checking your skin and attending all of your follow up doctor’s appointments. 
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Prevention

There are risk factors that you can and cannot control for melanoma.  You should try to reduce the risk factors that you can control.  You should perform a full body skin and mole inspection monthly.  It may be helpful to use a mirror or have someone else look at areas of your skin that are difficult for you to see.  Promptly report any suspicious moles or skin areas to your doctor.
 
The American Cancer Society recommends a yearly skin inspection by a qualified professional every year after the age of 40 and every three years for people ages 20-40.  If you experience skin cancer your doctor may recommend more frequent skin inspections.  You should make and attend all of your appointments.
 
You may be able to prevent skin cancer by limiting the amount of time that you are exposed to the sun.  Anyone that is exposed to the sun should wear a sunblock that blocks both UV A and B sunrays.  A sunscreen is a different product.  Sunscreens allow you to spend a longer amount of time in the sun without burning than you could if you were not wearing sunscreen. 
 
Most doctors recommend a sunblock that blocks both UV A and B rays and a sunscreen with a sun protection factor (SPF) of at least 15.  A SPF of 15 provides protection from burning for 150 minutes.  Sunscreen should be reapplied every 1 ½ hours or so depending on your activity level.
 
It is important to discard old sunblock and sunscreen.  Their effectiveness is reduced over time.  You should apply sunblock and sunscreen even in the winter.  Remember to apply it to all of your skin that is exposed including your hands, ears, lips, lower legs, the backs of your knees, and the tops of your feet.
 
It is beneficial to avoid being in the sun between the hours of 10 AM and 4 PM, when the sun’s rays are the strongest.  A good way to remember this is that if your shadow is shorter than you are tall, it is not a good time to be out in the sun.  You can still be outside, but seek shade.
 
If you must spend time in the sun, it is smart to wear hats with a broad rim and tightly woven fabrics that are especially made to block the sun.  Some clothing is rated for its SPF factor.  Your doctor is happy to refer you to such clothing suppliers. 
 
Wear sunglasses that block UVA and B sunrays.  Wrap-around styled sunglasses protect your eyes and your eye area.  Sun-related cancers can occur on the iris or inside of the eye on the retina.  Wear sunglasses and make sure that your eye doctor checks for cancer at each of your eye exams.
 
You should avoid sun tanning outside and sun tanning lamps or booths.  Artificial tanning lights give off harmful UV rays and can cause sunburns.  An alternative is to use self-tanning products or spray on coloring cosmetics.
 
You should stop smoking and avoid cancer causing chemicals.  If your job requires exposure to cancer causing agents, follow all of the safety instructions associated with the chemical use.  Wear protective masks and gear as instructed.
 
Teach your children about protecting their skin in the sun.  This is important because many skin cancers result from sunburns that occur before age 18.  Make sure that your children learn to apply and reapply sunblock and sunscreen when they are playing outdoors.
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Am I at Risk

Having one or more risk factors increases your likelihood of developing melanoma, although some people that experience this skin cancer may not have any risk factors.  People with all of the risk factors may never develop melanoma; however, the likelihood increases with the more risk factors you have.  You should tell your doctor about your risk factors and discuss your concerns. 


Risk factors for melanoma:


_____ People with light colored skin (Caucasians), blue eyes, green eyes, gray eyes, blond hair, or red hair have an increased risk for developing skin cancer.  However, people with darker complexions and dark hair may get skin cancer as well, but they have a lower risk.
_____ People that spent three or more summers as a teenager working in the sun, such as construction workers, farmers, fishermen, and lifeguards have an increased chance for developing melanoma.
_____ Too much exposure from UV radiation in sunlight or tanning lamps is a risk factor for melanoma.  This includes people that suntan outdoors, use artificial tanning lights, and
outdoor sport enthusiasts.
_____ Receiving three or more blistering sunburns before the age of 20 is a risk factor for developing melanoma.
_____ People that have had skin cancer, including melanoma, are at risk for developing melanoma.
_____ People with suppressed immune systems, such as organ transplant recipients or people that have AIDS, have an increased risk for melanoma.
_____ Your risk for melanoma increases with age. Most cases develop in people that are older, but it certainly can develop in younger people.
_____ People with 50 or more moles or some large moles have a higher risk of developing melanoma.
_____ People with freckled skin, especially on the shoulders, have a higher risk of developing melanoma.
_____ Melanoma can run in families.  If your close relatives have melanoma, you have an increased risk for developing it.
_____ People with xeroderma pigmentosum (XP), a rare genetic disorder, have an increased risk for developing melanoma.
_____ Actinic keratosis is a skin condition that can turn into melanoma.
_____ People with dysplastic or atypical moles are at an increased risk for developing melanoma.

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Advancements

Researchers have a good understanding of how the sun’s UV rays damage certain genes and cause skin cancer.  Scientists have found changes in genetic material that are both inherited and not inherited but often affected by sunlight.  It appears that some people can repair damage caused by the sun better than others can, and they are less likely to develop melanoma.  Researchers hope to use this information to develop gene therapies to prevent and cure melanoma. 
 
Researchers hope to use gene therapy in several ways.  Researchers anticipate replacing the damaged genes in cells with healthy genes.  So far, this approach has had limited success because usually there is more than one type of damaged gene in a melanoma cell.
 
A second approach is to add a specific gene to a melanoma cell to make the cell more sensitive to cancer fighting medications.  In preliminary studies, this type of gene therapy plus chemotherapy caused some metastatic melanoma tumors to shrink.
 
A third strategy is to add specific genes to melanoma cells as a vaccine.  The added cells help the immune system fight the cancer cells.  This strategy appears to work on altered and non-altered melanoma cells.
 
Researchers have discovered the BRAF gene, a gene mutation in many melanomas.  The BRAF gene is not inherited.  Researchers are studying medications that block the activity of this gene.
 
Researchers have identified the genes that are inherited and associated with an increased risk of developing melanoma.  Genetic testing is not available outside of a research setting at this time.  For now, scientists recommend that people with a family history of melanoma perform self-skin screenings and have routine professional skin examinations.
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This information is intended for educational and informational purposes only. It should not be used in place of an individual consultation or examination or replace the advice of your health care professional and should not be relied upon to determine diagnosis or course of treatment.

The iHealthSpot patient education library was written collaboratively by the iHealthSpot editorial team which includes Senior Medical Authors Dr. Mary Car-Blanchard, OTD/OTR/L and Valerie K. Clark, and the following editorial advisors: Steve Meadows, MD, Ernie F. Soto, DDS, Ronald J. Glatzer, MD, Jonathan Rosenberg, MD, Christopher M. Nolte, MD, David Applebaum, MD, Jonathan M. Tarrash, MD, and Paula Soto, RN/BSN. This content complies with the HONcode standard for trustworthy health information. The library commenced development on September 1, 2005 with the latest update/addition on February 16, 2022. For information on iHealthSpot’s other services including medical website design, visit www.iHealthSpot.com.