Melanoma is a skin cancer that begins in skin cells called melanocytes. These cells produce the pigment that provides your skin’s color. Although most melanomas occur in the skin, they can occur anywhere melanocytes reside, including the eye, intestines, and lymph nodes. Normal melanocytes divide, grow, and die in an orderly fashion. If this process becomes disorganized and unregulated, the result is an abnormal collection of melanocytes, also known as a melanoma. Malignant means that it has the potential to spread to healthy tissues and organs within your body. Although melanoma is not the most common skin cancer, it has the potential to be the most fatal, as it is very difficult to treat once it has metastasized, or spread.
Am I at risk? Despite the fact that it is almost impossible to predict who will acquire melanoma, a number of risk factors have been identified and include:
- Exposure to UV radiation (including natural sunlight and indoor tanning light)
- Fair skin
- A history of severe, blistering sunburns
- Many normal moles (usually more than 50)
- Abnormal-looking moles (also known as dysplastic nevi, they have the potential to evolve into melanomas)
- A weak immune system (as seen after organ transplantation or in persons with HIV)
- Personal or family history of melanoma
The good news is that, when caught early, melanomas are easy to diagnose and to treat. Along with regular visits to your dermatologist (the American Cancer Society recommends annual skin checks after the age of 40), monthly skin checks at home are invaluable. After all, in order to catch a melanoma in its early stages, you must be familiar enough with your own body to know when one of your moles appears different. Also keep in mind that melanomas can appear anywhere on your skin’s surface, so don’t ignore your scalp, back, soles of the feet and other hard-to-see areas. You may need multiple mirrors to reach every angle.
What should I look for? A useful acronym is the ABCDEs, which makes it easy to recall the warning signs of a potential melanoma:
A is for asymmetry: The two halves of one mole should be mirror-images. If you draw a line through the mole and the two sides do not match, it is considered to be asymmetrical.
B is for border: A normal mole has a nice, even border. Abnormal moles have irregular, jagged, and blurred borders. Sometimes, the color can seep into the surrounding skin.
C is for color: Moles with multiple colors (such as different shades of tans and browns, white areas, or even a predominantly red, blue, or black hue) should raise a red flag.
D is for diameter: Melanomas tend to be larger than your pencil’s eraser, which measures ¼ of an inch (the size of the white circle). You should also be concerned if one of your moles increases in size.
E is for evolving: In this case, change is not good. A change in size, symmetry, shape, color, height, border, or any such charactersitic may be a sign that abnormal cell division is occurring.
Another useful tip is to survey your skin for an “ugly duckling”. In other words, do any moles jump out at you as being very different from all of the others? It is important to trust your intuition, and to seek a professional medical opinion if something does not seem quite right.
How will my doctor know if I have a melanoma? In order to make the diagnosis, your doctor will have to biopsy the spot in question. Your doctor will cut a sample of the spot (or, alternatively, may sample the entire spot). The excised tissue will then be placed under the microscope, where abnormal cells are more easily identified.
What is the treatment for melanoma? The first line of therapy for melanoma is to excise, or cut out, the skin cancer. In addition to cutting out the melanoma itself, your doctor will take some of the surrounding tissue, in case the melanoma has invaded. Beyond excision, the extent of treatment depends on the microscopic characteristics of the tissue that is cut out. Your doctor will want to know if the melanoma has spread to other areas of your body. If there is concern for distant spread, your doctor may biopsy enlarged lymph nodes or may order imaging studies to look at the organs within your body. Subsequent treatment may include radiation therapy, chemotherapy, or biological therapy.
Where can I learn more?
American Academy of Dermatology
Images courtesy of NCI Visuals Online. Skin Cancer Foundation.