Kristin was worried. After a summer spent in the sun, she noticed a strange-looking mole on her shoulder. Since she'd just read an article about how more people in their teens and twenties are getting skin cancer, she decided to get the mole checked out.
Kristin made a doctor's appointment, but continued to worry in the days before the exam. What if it was cancer? Why hadn't she been more sensible about the sun? Fortunately, her mole was not cancerous. Her doctor reassured her that she'd done the right thing by having it checked — skin cancer is a lot easier to treat if it's caught early.
Although there are several different types of skin cancer, most don't become life-threatening because they aren't likely to spread to other parts of the body. Unfortunately, melanoma is different. If it's not caught early, melanoma can spread from the skin to other organs — often with deadly results.
If there's any good news about melanoma, it's this: You have the power to substantially lower your risk of getting it. All it will cost you is a little extra time spent protecting yourself from the sun and paying attention to the moles on your skin.
What Is Melanoma?
Melanoma is a type of cancer that begins in the melanocytes. Melanocytes are skin cells that produce melanin, the pigment that gives skin its color.
Melanocytes commonly cluster together to form skin growths called moles (or "nevi," in medical terms). Most people have several moles — maybe even dozens — and they usually don't cause any problems. Moles may be flat or raised, large or small, light or dark, and can appear anywhere on our bodies.
Sometimes, though, melanocytes can malfunction. Because of a genetic change, they can begin growing out of control, sticking together to form lesions or tumors, crowding out healthy cells, and damaging surrounding tissue. This condition is known as cancer.
Melanoma that's caught early, when it's still on the surface of the skin, can be cured. But if melanoma is ignored or untreated, it can grow downward into the skin until it reaches the blood vessels and lymphatic system. These two systems can act like a highway for the cancer cells, allowing them easy access to distant organs like the lungs or the brain. That's why early detection is so important.
How Do People Get It?
How does a normal melanocyte become malignant (cancerous)? Researchers believe it's probably a combination of genes and the things we do, like tanning.
One of the most important contributors to melanoma is ultraviolet (UV) sun damage. Cells that have been damaged — particularly by short bouts of bad, blistering sunburns during childhood or regular tanning bed use as a teen or young adult — are more likely to become cancerous over time.
The jury is still out, but some experts think that factors like the thinning of the ozone layer or clothing styles that expose more skin also may contribute to a person's risk of skin cancer. It's also thought that, as people live longer and become more are aware of the disease, more cases of skin cancer are naturally going to be diagnosed. But more likely today's melanoma rates have as much to do with lingering misconceptions about tanning from generations ago.
Back in your parents' and grandparents' day, most people (including doctors) thought it was safe and even healthy to lather up with oil and tan as much as you wanted — just as they thought it was OK to smoke in hospital rooms, which seems crazy now! Even tanning beds and sun lamps were touted as being safer than the sun when they first became popular in the 1980s.
Today we certainly know better. Experts know that certain risk factors increase a person's chance of developing melanoma, including:
- a fair complexion (light skin that freckles or burns easily, blue eyes, or blond or red hair)
- multiple moles (typically more than 25)
- UV exposure (whether from the sun or a tanning bed)
- a history of frequent or severe sunburns
- a relative with melanoma or a family history of irregular moles
- age (older people are still at greater risk)
- a previous melanoma (moles typically don't grow back after being removed, but a person who's had melanoma once is more likely to have a recurrence somewhere else)
Although it's less likely, you can still get melanoma even if you're dark skinned, young, and have no family history. It appears that behavior — too much sun exposure and not enough skin protection — can override the other risk factors.
How Do People Know They Have It?
Many melanomas start out as a mole or a bump on the skin. Of course, not every mole is cancerous — far from it. What's more telling is whether a mole has undergone any kind of recent change, whether in size, shape, or color.
That's why it's important to take a mental snapshot of your skin — kind of like a mole roadmap — so you'll know what's normal for you. With that as a baseline, you'll be able to spot any changes early. Keep the ABCDE rule in mind when checking your moles:
- A for asymmetry: If you were to cut the mole down the middle, would the left and the right sides look different?
- B for border: Are the edges blurry and undefined? Does it appear to be spreading sideways?
- C for color: Does the mole look darker or lighter than usual, or does it have an area of new color — perhaps black, blue, purple, red, or white?
- D for diameter: Is the mole larger than the eraser on a pencil top?
- E for evolving: Has the size, shape, or color changed over time?
If you answered yes to any of these questions about an existing mole — or if you have a new mole, or one that's started to itch or bleed — see your doctor right away.
The most common places for melanoma to occur are on the torso, head, and neck for men, and the lower legs for women. African Americans are more likely to get melanoma under the nails, or on the palms and soles of the feet.
If a doctor suspects melanoma, he or she will perform a biopsy — removing all or part of the mole in question and examining its cells under a microscope. Not only can a biopsy tell if the cells are cancerous, but it can also be used to tell how deeply cancer has penetrated the skin and predict its risk of spreading. Knowing these details will help the doctor map out a treatment plan.
How Do Doctors Treat It?
What doctors do about melanoma depends on how big and deep the cancerous area (known as a "lesion") is, what part of the body it's on, and whether it has spread to other parts of the body.
Treatment for melanoma typically includes surgery to remove the lesion. If doctors suspect that cancerous cells may have traveled to other areas of the body, treatment may also include radiation (high-energy X-rays that are directed at tumors) or chemotherapy (cancer-fighting drugs). Doctors may also use immunotherapy (also known as biologic therapy), a treatment that stimulates the body's own immune system to fight cancer cells, alongside these other treatments.
How Can You Prevent It?
Although you can't control how fair your skin is or whether you have a relative with cancerous moles, there are several things you can do to lower your risk of developing melanoma. The most important is limiting your exposure to the sun. Take these precautions:
- Avoid the strongest sun of the day — between 10 a.m. and 4 p.m.
- Use broad-spectrum sunscreen (SPF 30 or more) whenever you're in the sun.
- Wear a wide-brimmed hat and cover up with long, loose cotton clothing if you burn easily.
- Stay out of the tanning salon. Even one indoor tanning session increases your risk of getting melanoma.
Also, be sure to check your moles often (you may need to ask a friend to help with those hard-to-reach areas, like your back and scalp). Keep dated records of each mole's location, size, shape, and color, and don't wait to have anything suspicious checked out.
Not all skin cancer is melanoma, but every case of melanoma is serious. So now that you know more about it, take responsibility for protecting yourself and do what you can to lower your risk.
Reviewed by: Rupal Christine Gupta, MD
Date reviewed: September 2014
Originally reviewed by: Christopher N. Frantz, MD