Melanoma, the most serious type of skin cancer, develops in the cells that produce melanin — the pigment that gives your skin its color. Melanoma can also form in your eyes and, rarely, in internal organs, such as your intestines. The exact cause of all melanomas isn't clear, but exposure to ultraviolet (UV) radiation from sunlight or tanning lamps and beds increases your risk of developing melanoma. Other factors, such as your genetic makeup, likely also play a role. Limiting your sun exposure and avoiding tanning lamps and beds can help reduce your risk of melanoma. And making sure you know the warning signs of skin cancer can help ensure that cancerous changes are detected and treated before the cancer has a chance to spread. Melanoma can be treated successfully if it is detected early.
Causes of Melanoma Tumor
Melanoma occurs when something goes awry in the melanin-producing cells (melanocytes) that give color to your skin. Normally, skin cells develop in a controlled and orderly way — healthy new cells push older cells toward your skin's surface, where they die and eventually are sloughed off. But when some cells develop DNA damage, new cells may begin to grow out of control and can eventually form a mass of cancerous cells.
Just what damages DNA in skin cells and how this leads to melanoma isn't clear. It's likely that a combination of factors, including environmental and genetic factors, causes melanoma. Still, doctors believe exposure to ultraviolet (UV) radiation from the sun and from tanning lamps and beds is the leading cause of melanoma.
UV light doesn't cause all melanomas, especially those that occur in places on your body that don't receive exposure to sunlight. This indicates that other factors may contribute to your risk of melanoma.
Signs & Symptoms of Melanoma Tumor
Melanomas can develop anywhere on your body, but they most often develop in areas that have had exposure to the sun, such as your back, legs, arms and face. Melanomas can also occur in areas that don't receive much sun exposure, such as the soles of your feet, palms of your hands and on fingernail beds. These hidden melanomas are more common in people with darker skin.
The first melanoma symptoms often are:
Melanoma doesn't always begin as a mole. It can also occur on otherwise normal-appearing skin.
Normal moles are generally a uniform color, such as tan, brown or black, with a distinct border separating the mole from your surrounding skin. They're oval or round and usually smaller than 1/4 inch (6 millimeters) in diameter — the size of a pencil eraser. Most people have between 10 and 40 moles. Many of these develop by age 40; although moles may change in appearance over time — some may even disappear with age.
Unusual moles that may indicate melanoma
Characteristics of unusual moles that may indicate melanomas or other skin cancers follow the A-B-C-D-E guide developed by the American Academy of Dermatology:
A is for asymmetrical shape. Look for moles with irregular shapes, such as two very different-looking halves.
B is for irregular border. Look for moles with irregular, notched or scalloped borders — characteristics of melanomas.
C is for changes in color. Look for growths that have many colors or an uneven distribution of color.
D is for diameter. Look for new growth in a mole larger than about 1/4 inch (6 millimeters).
E is for evolving. Look for changes over time, such as a mole that grows in size or that changes color or shape. Moles may also evolve to develop new signs and symptoms, such as new itchiness or bleeding.
Other suspicious changes in a mole may include:
Cancerous (malignant) moles vary greatly in appearance. Some may show all of the changes listed above, while others may have only one or two unusual characteristics.
Melanomas can also develop in areas of your body that have little or no exposure to the sun, such as the spaces between your toes and on your palms, soles, scalp or genitals. These are sometimes referred to as hidden melanomas; because they occur in places most people wouldn't think to check. When melanoma occurs in people with darker skin, it's more likely to occur in a hidden area.
Hidden melanomas include:
Melanoma under a nail. Subungual melanoma is a rare form that occurs under a nail and can affect the hands or the feet. It's more common in blacks and in other people with darker skin pigment. The first indication of a subungual melanoma is usually a brown or black discoloration that's often mistaken for a bruise (hematoma).
Melanoma in the mouth, digestive tract, urinary tract or vagina. Mucosal melanoma develops in the mucous membrane that lines the nose, mouth, esophagus, anus, urinary tract and vagina. Mucosal melanomas are especially difficult to detect because they can easily be mistaken for other, far more common conditions. A melanoma in a woman's vagina can cause itching and bleeding. Anal melanoma can cause anal bleeding and pain during bowel movements. Melanoma that occurs in the esophagus can cause difficulty swallowing.
Melanoma in the eye. Eye melanoma, also called ocular melanoma, occurs in the uvea — the layer beneath the white of the eye (sclera). An eye melanoma may cause vision changes and may be diagnosed during an eye exam.
Diagnosis of Melanoma Tumor
Skin cancer screening
Ask your doctor whether you should consider periodic screening for skin cancer. You and your doctor may consider screening options such as:
Skin exams by a trained professional. The American Cancer Society (ACS) recommends periodic skin exams as part of your usual checkups with your doctor. During a skin exam, your doctor conducts a head-to-toe inspection of your skin.
Skin exams you do at home. In addition, the ACS and the American Academy of Dermatology recommend occasional self-exams. A self-exam may help you learn the moles, freckles and other skin marks that are normal for you, so you can notice any changes. It's best to do this standing in front of a full-length mirror while using a hand-held mirror to inspect hard-to-see areas. Be sure to check the fronts, backs and sides of your arms and legs. In addition, check your groin, scalp, fingernails, your soles and the spaces between your toes. Other groups don't recommend skin cancer screening exams because it's not clear whether screening saves lives. Instead, finding an unusual mole could lead to a biopsy, which, if the mole is found to not be cancerous, could lead to unnecessary pain, anxiety and cost. Talk to your doctor about what screening is right for you, based on your risk of skin cancer.
Sometimes cancer can be detected simply by looking at your skin, but the only way to accurately diagnose melanoma is with a biopsy. In this procedure, all or part of the suspicious mole or growth is removed, and a pathologist analyzes the sample. Biopsy procedures used to diagnose melanoma include:
Punch biopsy. During a punch biopsy, your doctor uses a tool with a circular blade. The blade is pressed into the skin around a suspicious mole and a round piece of skin is removed.
Excisional biopsy. In this procedure, the entire mole or growth is removed, along with a small border of normal-appearing skin.
Incisional biopsy. With an incisional biopsy, only the most irregular part of a mole or growth is taken for laboratory analysis.
The type of skin biopsy procedure you undergo will depend on your situation.
If you receive a diagnosis of melanoma, the next step is to determine the extent, or stage, of the cancer. To assign a stage to your melanoma, your doctor will:
Determine the thickness. The thickness of a melanoma is determined by carefully examining the melanoma under a microscope. The thickness of a melanoma helps doctors decide on a treatment plan. In general, the thicker the tumor, the more serious the disease.
See if the melanoma has spread. To determine whether your melanoma has spread to nearby lymph nodes, your surgeon may use a procedure known as a sentinel node biopsy. During a sentinel node biopsy, a dye is injected in the area where your melanoma was removed. The dye flows to the nearby lymph nodes. The first lymph nodes to take up the dye are removed and tested for cancer cells. If these first lymph nodes (sentinel lymph nodes) are cancer-free, there's a good chance that the melanoma has not spread beyond the area where it was first discovered. Melanoma is staged using the Roman numerals I through IV. A stage I melanoma is small and has a very successful treatment rate. But the higher the numeral, the lower the chances of a full recovery. By stage IV, the cancer has spread beyond your skin to other organs, such as your lungs or liver.
Treatments of Melanoma Tumor
The best treatment for you depends on your stage of cancer and your age, overall health and personal preferences.
Treating early-stage melanomas
Treatment for early-stage melanomas usually includes surgery to remove the melanoma. A very thin melanoma may have been entirely removed during the biopsy and require no further treatment. Otherwise, your surgeon will remove the cancer as well as a small border of normal skin and a layer of tissue beneath the skin. For people with early-stage melanomas, this may be the only treatment needed.
Treating melanomas that have spread beyond the skin
If melanoma has spread beyond the skin, treatment options may include:
Surgery to remove affected lymph nodes. If melanoma has spread to nearby lymph nodes, your surgeon may remove the affected nodes. Additional treatments before or after surgery may also be recommended.
Chemotherapy. Chemotherapy uses drugs to destroy cancer cells. Chemotherapy can be administered intravenously, in pill form or both, so that it travels throughout your body. Or chemotherapy can be administered in a vein in your arm and leg in a procedure called isolated limb perfusion. During this procedure, blood in your arm or leg isn't allowed to travel to other areas of your body for a short time, so that the chemotherapy drugs travel directly to the area around the melanoma and don't affect other parts of your body.
Radiation therapy. This treatment uses high-powered energy beams, such as X-rays, to kill cancer cells. It's sometimes used to help relieve symptoms of melanoma that has spread to another organ. Fatigue is a common side effect of radiation therapy, but your energy usually returns once the treatment is complete.
Biological therapy (immunotherapy). Biological therapy boosts your immune system to help your body fight cancer. These treatments are made of substances produced by the body or similar substances produced in a laboratory. Biological therapies used to treat melanoma include interferon and interleukin-2. Side effects of these treatments are similar to those of the flu, including chills, fatigue, fever, headache and muscle aches.
Experimental melanoma treatments
Clinical trials are studies of new treatments for melanoma. Doctors use clinical trails to determine whether a treatment is safe and effective. People who enroll in clinical trials have a chance to try evolving therapies, but a cure isn't guaranteed. And sometimes the potential side effects aren't known.
Some melanoma treatments being studied in clinical trials include:
Combining chemotherapy and biological therapy. Combining chemotherapy and biological therapy drugs may increase the success of both of these treatments. However, combining treatments can make severe side effects more likely.
Targeted therapy. Targeted therapies interrupt a specific process in cancer cells in order to control cancer. For instance, targeted drugs designed to stop melanoma from attracting blood vessels have been tested. Melanoma needs blood vessels to deliver nutrients and it uses blood vessels to spread cancer cells throughout the body. A drug that stops this process could cause a melanoma to remain small and localized. In another approach, specific chemicals that stimulate cancer cells to grow rapidly could be inactivated.
Vaccine treatment. Vaccines for treating cancer are different from vaccines used to prevent diseases. Vaccine treatment for melanoma might involve injecting altered cancer cells into the body to draw the attention of the immune system.
Prevention of Melanoma Tumor
The best news about melanoma is that many cases of skin cancer can be prevented by following these straightforward precautions:
Avoid midday sun. Avoid the sun when its rays are the strongest. For most places, this is between about 10 a.m. and 4 p.m. Because the sun's rays are strongest during this period, try to schedule outdoor activities for other times of the day, even in winter or when the sky is cloudy. You absorb UV radiation year-round, and clouds offer little protection from damaging rays.
Wear sunscreen year-round. Choose a broad-spectrum sunscreen that has a sun protection factor (SPF) of at least 15. Use a generous amount of sunscreen on all exposed skin, including your lips, the tips of your ears, and the backs of your hands and neck. Apply sunscreen 20 to 30 minutes before sun exposure and reapply it frequently while you're exposed to the sun. Be sure to reapply it after swimming or exercising.
Wear protective clothing. Sunscreens don't provide complete protection from UV rays, so wear tightly woven clothing that covers your arms and legs, and a broad-brimmed hat, which provides more protection than a baseball cap or visor does. Some companies also sell photo protective clothing. Your dermatologist can recommend an appropriate brand. Don't forget sunglasses. Look for those that block both types of UV radiation — UVA and UVB rays.
Avoid tanning beds. Tanning beds emit UV radiation, which can increase the risk of skin cancer.
Become familiar with your skin, so you'll notice changes. Examine your skin so that you become familiar with what your skin normally looks like. This way, you may be more likely to notice any skin changes. With the help of mirrors, check your face, neck, ears and scalp. Examine your chest and trunk, and the tops and undersides of your arms and hands. Examine both the front and back of your legs, and your feet, including the soles and the spaces between your toes. Also check your genital area, and between your buttocks. If you notice anything unusual, point it out to your doctor at your next appointment.
When to seek Medical Advice
Make an appointment with your doctor if you notice any skin changes that seem unusual.