Melanoma Facts
This form of cancer begins in the melanocytes cells, which make melanin, the pigment that determines our natural skin color. Melanoma is much more serious than basal and squamous cell carcinomas. It can spread quickly to other organs and causes 75 percent of skin cancer deaths in the United States.
Melanomas usually develop on or around an existing mole. Since the cells usually continue to make melanin, melanoma tumors are often brown or black.
Common places for melanoma to occur are on men’s trunks and women’s lower legs, but they can occur elsewhere, such as in the eye (ocular or intraocular melanomas). Rarely, melanoma shows up in the meniges (the membrane that covers the brain and the spinal marrow), the digestive tract, lymph nodes, or other areas where melanocytes are found.
In the first stage, melanoma begins as “melanoma in situ,” meaning it doesn’t grow much beyond the epidermis. If it is not removed when it is thin, the melanoma can penetrate deeply into the dermis and may spread throughout the body.
Types of melanoma
There are four basic types of melanoma. If you or someone you care about has been diagnosed with melanoma, talk to your physician for further information on the specific type. The first three types of melanoma are “in situ” melanomas (Latin for “localized”).
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Superficial spreading melanoma
This is the most common type of melanoma and accounts for about 70 percent of all melanomas. It travels along the top layer of the skin for a long time before going deeper into the skin. It can be found almost anywhere on the body, but is most likely to be on the trunks of men, legs of women, and upper backs of both. Superficial spreading melanoma mostly affects adults but young people develop it as well.
Appearance The first sign is a flat or slightly raised, somewhat geometrical, discolored patch with irregular borders. The color varies, with possible areas of tan, brown, black, red, blue, or white. Sometimes an older mole will turn into this kind of melanoma. - Acral lentiginous melanoma
This melanoma also spreads superficially before growing deeper into the skin. It is usually found under the nails, on the soles of the feet, or the palms of the hands. Acral lentiginous melanoma is the most common melanoma in African-Americans and Asians, and the least common among whites.
Appearance It appears as a black or brown discoloration.
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Lentigo maligna
This melanoma is similar to the superficial spreading type. It stays close to the skin’s surface for a long time, but becomes invasive more quickly than the other two. This melanoma is most often found in elderly people, showing up on the face, ears, arms and upper trunk—skin chronically exposed to and damaged by sun exposure. Lentigo maligna is the most common form of melanoma in Hawaii.
Appearance Usually appears as a flat or mildly elevated mottled tan, brown or dark brown discoloration. -
Nodular melanoma
This fourth kind of melanoma is usually already invasive when first diagnosed. This very invasive cancer is commonly located on an older person’s trunk, legs, and arms and on the scalp of men at any age.
Appearance This malignancy is recognized when it becomes a bump, most often black, but occasionally blue, gray, white, brown, tan, red or skin tone.
Risk Factors
Everyone is at some risk for skin cancer, but certain factors increase this risk. Most risk factors apply to all three of the major skin cancers, but there are certain factors associated with only non-melanoma skin cancers and others that pertain to only melanoma. Read below about all three risk categories:
These factors relate to all three of the major skin cancers. If any apply to you, it is extremely important to take proper precautions to protect yourself by limiting your sun exposure and using sunscreen.
- Coloring
If you have fair skin, blond, red, or light brown hair, blue eyes, or freckles your risk is increased. According to the American Cancer Society, the risk of melanoma is about 20 times higher for whites than for African-Americans. The reason lies in the pigment melanin. More melanin accounts for darker skin, which has the ability to tan more easily, block out damaging sun rays, and keep darker-skinned people from becoming sunburned as easily as fair-skinned people. Despite this, it is important to remember that anyone can get skin cancer.
- Blistering sunburns
If you have experienced several blistering sunburns as a child or teen, or if you burn before you tan, you are at increased risk for skin cancer.
- Sun exposure
If you spend a lot of time outdoors for work or recreation, you are at increased risk.
- Weekend sun
If you work indoors all week and then are exposed to sun on the weekends, while, for example, swimming, washing the car without a shirt on, playing volleyball at the beach, coaching soccer, or gardening, your risk is increased.
- Climate
If you live or vacation in tropical and subtropical climates and areas with year-round, bright sunlight, you are at increased risk for skin cancer. (The risk of developing non-melanoma cancer is twice as high in Arizona as in Minnesota.)
- Altitude
If you live, work, or vacation at high altitudes, you are at increased risk. Ultraviolet radiation from the sun increases 4 to 5 percent for every 1,000 feet above sea level.
- Personal history
If you have been treated for skin cancer in the past, your risk is higher.
- Family history
You are at higher risk for skin cancer when one or more “first degree” relatives: father, mother, sisters, brothers, or children have had skin cancer. The more family members that have or have had skin cancer, the higher your risk.
- Xeroderma pigmentation
This is a rare, inherited skin condition, where a person’s body cannot repair DNA damage caused by ultraviolet lights. People with xeroderma pigmentation are at risk for damage to their eyes as well as for the three types of skin cancers discussed here. Symptoms can begin in childhood.
- A weakened immune system
You are at higher risk for skin cancer if you are taking medications for an organ transplant, have AIDS, cancer, or are on immune-suppressant drugs.
- Artificial tanning
Use of tanning beds, booths, or sunlamps increases risk. For more information on these and other risks from artificial tanning, click here.
- Medications
Ask your doctor, nurse, or pharmacist if any of the medications you are taking could be harmful when you are out in sunlight, or if they make you more prone to sun damage. These include medicines such as tetracycline, sulfa drugs and some other antibiotics; naproxen sodium, ibuprofen and some other nonsteroidal anti-inflammatory drugs (NSAIDs); phenothiazines (sedatives and anti-nausea drugs), tricyclic antidepressants, thiazide diuretics (medications used for high blood pressure and other conditions), sulfonylureas (an oral anti-diabetic medication), or medications that lower your body’s immunity.
Melanoma risk factors
These risk factors are specific to melanoma:
- Age
Your chances of developing melanoma increase with age. A 70-year-old’s risk of developing melanoma is twice that of a 45-year-old. At the same time, it is one of the most common cancers in people under 30 years old.
- Sex
One in 57 men will develop melanoma as opposed to one in 81 women.
- Family history of breast or ovarian cancer
Anyone who has close family members with one or both of these cancers may be at increased risk of melanoma, mostly likely because of a similar kind of gene mutation.
- Moles
A mole (“nevus”) is a benign (noncancerous) tumor that usually begins during the childhood or teenage years. A mole is a collection of pigment cells that are usually round or oval, flat or raised, symmetrical with smooth borders, and are one of several colors. It is a good idea to be on the alert and check your moles regularly. On average, people have between 10 and 40 moles, with new ones appearing until middle adulthood. A chance of any single mole becoming cancerous is low: around 1 in 2,000 for men and one in 9,000 for women. People with lots of moles or who have large moles are at a higher risk for melanoma.
- Dysplastic (“atypical”) nevus
These moles develop from childhood on through the adult years and often run in families. If you have family members with dysplastic nevi (plural) you have a 50 percent chance of developing them. Lifetime melanoma risk for those with dysplastic nevi is between 6 and 10 percent, depending on age, family history, the number of dysplastic nevi, and other factors.
- Congenital melanocytic nevi
These moles are present at birth and bring about a 6 percent lifetime risk. The larger the melanocytic nevi, the greater the risk.
Increased risk for children
Children love fun in the sun. But they are extremely susceptible to sun damage, which often leads to skin cancer later in life. Studies show that intense sun exposure and blistering sunburns increase the risk for melanoma, which can sometimes be fatal.
Stages
The stage of your cancer helps determine your best treatment options. The process of staging determines whether or not your cancer has spread, and, if it has, how far. When skin cancer is diagnosed at an early stage, it is more likely to be cured. Quite often, a biopsy is the only test needed to determine the stage of a non-melanoma cancer. In the case of squamous cell carcinomas, doctors often examine the surrounding lymph nodes to see if the cancer has spread.
Melanoma cancer stages:
Stage 0
Carcinoma “in situ.” The cancer is found only in the epidermis (the topmost, outer layer of your skin).
Stage I
Stage I is divided into IA and IB:
Stage IA
1. The tumor is in the epidermis and upper layer of the dermis.
2. It is not more than 1 millimeter (less than 1/16 of an inch thick).
3. There is no ulceration.
Stage IB
1. The tumor is not more than 1 millimeter thick.
2. It has an ulceration.
3. It may have spread into the dermis or tissue below the skin.
OR
1. The tumor is 1 to 2 millimeters (more than 1/16 inch) thick.
Stage II
Stage II is divided into IIA, IIB and IIC.
Stage IIA
1. The tumor is 1 to 2 millimeters thick.
2. It has an ulceration.
OR
1. The tumor is 2 to 4 millimeters thick.
2. It has no ulcerations.
Stage IIB
1. The tumor is 2 to 4 millimeters thick.
2. It has an ulceration.
OR
1. The tumor is more than 4 millimeters thick.
2. It has no ulceration.
Stage IIC
1. The tumor is 4 millimeters thick.
2. It has an ulceration.
Stage III
The tumor may be any thickness, without any ulceration, and it may have spread to one or more nearby lymph nodes. Stage III includes IIIA, IIIB and IIIC.
Stage IIIA
1. The cancer has spread to as many as three nearby lymph nodes.
2. It can only be seen with a microscope.
Stage IIIB
1. The cancer has spread to as many as three lymph nodes.
2. It may not be visible without a microscope.
OR
1. The cancer has satellite tumors, but it has not spread to the lymph notes.
Stage IIIC
1. The cancer has spread to as many as four or more lymph nodes.
2. It can be seen without a microscope.
OR
1. The cancer has lymph nodes that may not be moveable.
OR
1. The satellite tumors may have spread to lymph nodes.
Stage IV
The cancer has spread to other organs or to lymph nodes far away from the original tumor site.