Melanoma is a serious form of skin cancer.
Melanoma symptoms can be subtle and difficult to differentiate from moles. Melanoma is a type of cancer that most commonly affects areas of the skin frequently exposed to ultraviolet radiation, such as the neck, legs, face and torso. While it tends to form tumors in the skin, melanoma is known for its tendency to metastatize, or spread, to other organs and areas of the body, in particular the lymph nodes, brain and lungs. Although it is much rarer than basal and squamous cell carcinomas, melanoma is far more dangerous and causes more deaths per year than any other kind of skin cancer.
Unlike other types of cancer, melanoma affects special skin cells called melanocytes. Located in the top layer of the skin, or epidermis, these cells produce a pigment called melanin that gives skin its color. When these cells become cancerous, they form tumors that appear as dark spots on or beneath the skin's surface. Because these tumors often look like moles, it can be difficult to know whether they're dangerous. To help people determine if their moles might in fact be malignant melanomas, the American Academy of Dermatology developed a simple test known as the A-B-C-D-E Guide, which stands for asymmetrical, borders, colors, diameters and evolving. According to the guide, look for the following during self-examination:
Although the guide is only a rough indicator of potential melanoma, it is extremely easy to use and works for people of all ages. Other warning signs that a mole may contain melanoma are itchiness, scaliness, hardness, oozing and bleeding. Anyone presenting any of these symptoms should see a general practitioner or dermatologist for further diagnosis and potential treatment.
Although most melanomas occur in the top layer of skin, some occur in other parts of the body that also contain melaoncytes. According to the Mayo Clinic, these hidden melanomas most commonly occur in the eye, digestive tract, mouth and vagina, as well as beneath the fingernails.
Melanoma of the eye, also known as ocular melanoma, usually appears in either the retina, the inner lining of the eyelid or the pigmented tissue within the eyeball. Because of its location deep within the eye, retinal melanoma is difficult to detect and typically goes unnoticed until the patient undergoes an eye exam. The other two eye cancers, however, cause noticeable symptoms, including itchiness and dark spots in the field of vision, and are thus easier to detect.
Melanomas growing in mucous membranes and the skin beneath fingernails often cause symptoms similar to other diseases and conditions. For example, a dark melanoma under a fingernail may appear to be a simple bruise or blood blister, while a melanoma in either the digestive or female genital tract may produce itchiness and bleeding, symptoms commonly associated with both hemorrhoids and yeast infections. Regular physical exams can help detect these internal melanomas before they become life-threatening.
Skin cancer is the most common of all cancers in the United States, accounting for an estimated half of all cancers diagnosed each year. However, melanoma is extremely rare, accounting for only 5 percent of all skin cancer cases. Nevertheless, according to the American Cancer Society (ACS), of the nearly 63,000 people that will be diagnosed with melanoma in 2008, approximately 8,500 will die as a result of the cancer, a frightening statistic that gives scale to the magnitude of the disease.
Worth noting, however, is the fact that likelihood of developing melanoma varies with ethnicity -- the ACS estimates that 2 percent of whites, 0.1 percent of African Americans and 0.05 percent of Hispanics will develop the cancer sometime in their lives. Although the higher level of melanin in their skin protects African Americans and Hispanics against developing melanoma to a degree, they are especially vulnerable to tumors that form on the soles of their feet and the skin beneath their nails. In fact, melanomas forming on these areas account for nearly half of all melanomas in African Americans, while they only account for 10 percent of the cancer in whites. Regardless of ethnicity, the best way for a person to lower their risk of developing melanoma is by protecting their body from strong sunlight and other forms of UV radiation.