Characteristics of a common mole include:. Many moles can darken after exposure to the sun, but it is important to note that these moles are not precancerous lesions.
Instead, they are just the result of melanocytes, or clustered cells in the skin, that create the darker pigmentation. From childhood to middle age, normal moles can change, becoming more raised or different in color, sometimes even sprouting hair.
Some people choose to have normal moles removed. However, this procedure is cosmetic and very different from the removal of a precancerous or cancerous mole. Do you want to learn everything you need to know about skin cancer: What to expect, how do you treat it, and how it will affect your life? Download our free eBook today and get your questions answered.
An atypical mole, also known as a dysplastic nevus, is a mole that looks different than common moles. Atypical moles form anywhere on the body including the scalp, breasts, or legs, but are often found in areas that are frequently exposed to the sun.
Most people with atypical moles also have more common moles than usual. Atypical moles are very similar to melanoma: both are asymmetrical, multicolored, have an irregular border, and can grow over time. While not all atypical moles are precancerous moles, they can become cancerous moles or melanoma. It is important to understand the characteristics of an atypical mole so that if you detect one on your body, you can seek the help of a professional to make a diagnosis and treatment plan if necessary.
As mentioned earlier, an atypical mole can turn into a precancerous mole, specifically melanoma. However, research indicates that most atypical moles remain stable over time. People with more than 40 moles or more than five dysplastic nevi have a greater risk of developing skin cancer. Protecting yourself from harmful ultraviolet radiation emitted by the sun is especially important for people that already have a high number of common moles or atypical moles.
Always wear sunscreen or protective clothing. Doctors recommend that people with atypical moles perform a self-check on their skin once a month. During these routine checks, look for the following in atypical moles:. If you notice any changes in color, size, texture, and shape, speak to your doctor right away.
Atypical moles rarely need to be removed as long as they do not show any of the changes listed above, in which they may be precancerous moles and need to be removed right away.
Most doctors recommend regular monitoring of atypical moles. While it is possible for a dysplastic nevus to turn into a melanoma, the chance is very low.
However, you can elect to have an atypical mole removed for cosmetic reasons. Precancerous moles, more commonly referred to as precancerous skin lesions, are growths that have an increased risk of developing into skin cancer. Precancerous skin lesions, usually referred to as actinic keratosis or solar keratoses, can cause different types of skin cancer, including:. There are different causes of skin cancer and many of these involve sun exposure.
When people are exposed to the sun, the ultraviolet radiation often damages the DNA of the skin cells themselves. As the DNA is damaged, the cells are unable to produce proteins and cannot correctly respond to the various signals of the body. As a result, they divide out of control and lead to the symptoms of cancer. Therefore, it is important to spot a precancerous lesion before it gets too big.
There are several signs that set precancerous moles or skin lesions apart from the standard mole. These include:. A common mole is typically symmetrical. It is round, sometimes elevated, and shaped evenly. On the other hand, precancerous or cancerous moles are asymmetrical. They rarely turn into cancer, unless you have more than 50 of them.
Less common are atypical moles dysplastic nevi. About 1 out of every 10 Americans has at least one atypical mole. The more of these moles you have, the greater your risk of developing melanoma — the deadliest type of skin cancer. Having 10 or more atypical moles increases your risk fold. Because an atypical mole has the potential to turn into melanoma, knowing which type you have and watching for any changes can help you get an early diagnosis if it is cancer.
Experts suggest that you do monthly skin self-exams, checking your entire body — including less obvious areas like the soles of your feet, your scalp, and the skin underneath your fingernails — for any new or changing growths. An atypical mole can form anywhere on your body, including your head, neck, scalp, and torso.
They rarely appear on the face. Examine your skin once a month in front of a full-length mirror. Check every part of your body, including:. If you have atypical moles, you should also see your dermatologist for checkups every six months to one year. Any new, suspicious-looking, or changing spots should prompt an immediate visit to your dermatologist.
Although most atypical moles never turn into cancer, some of them can. If you do have melanoma, you want to have it diagnosed and treated early, before it has a chance to spread.
Your doctor will examine your moles. He or she will probably take a sample of tissue from one or more of the moles. This test is called a biopsy. Preventive Services Task Force has found insufficient evidence to assess the balance of benefits and harms of routine screening for skin cancer by clinicians or patients, but acknowledges that screening in high-risk populations may have value. Of these factors, personal and family histories of melanoma are the most important. Although periodic self-examinations and physician examinations may increase detection of thin melanomas amenable to surgery, it may be that close surveillance detects more slow-growing lesions with an inherently favorable prognosis.
The evidence for improved survival is less compelling. Total body photographs, with copies given to the patient, may be considered for observational aid and reassurance, especially in patients with a large number and variety of moles.
There is some evidence to suggest an increased melanoma yield based on photographic change in lesions that were not strongly suspected to be melanoma by appearance alone. Although atypical moles are associated with an increased risk of melanoma, most melanomas do not arise from existing atypical moles, and this should guide biopsy decisions. A strategy of photographic and physical follow-up, for example, results in a reasonable ratio of 10 biopsies per melanoma discovered.
The primary goal of biopsy is to rule out melanoma in patients who develop suspicious lesions during surveillance. A secondary goal is to accurately determine the depth of penetration should a melanoma be found because this is the histologic factor most predictive of metastasis and survival. Biopsy techniques include excisional, punch, deep shave scoop, scallop, or saucerization , and superficial shave biopsies. Full epidermal and dermal excisional biopsy, including the entire lesion with at least 4 mm in depth and a narrow 2-mm margin, is the preferred method because it provides the pathologist with the entire specimen, eliminating sampling variability.
Clinicians have traditionally been advised against performing shave biopsy of skin lesions when there is significant suspicion of melanoma, out of concern that this technique could make accurate determination of lesion thickness difficult and that scarring could obscure the development of a recurrent lesion. However, studies have shown that a deep shave biopsy performed by an experienced clinician using the saucerization technique can usually achieve a depth that allows a valid appraisal of penetration depth, and it may even be preferable to punch biopsy when melanoma makes up only a small portion of a larger lesion.
When melanoma is ruled out in a biopsied mole that displays atypia extending to or very near the margin of the excision, it is common practice to reexcise the lesion. This is likely not necessary because clinical recurrence of lesions with mild to moderate atypia extending to the margin is extremely rare on prolonged follow-up. Lesions with moderate to severe atypia may benefit from reexcision. Preventive Services Task Force. Search dates: July 6, , and January 29, Figures 2 through 5 courtesy of Amy Morris, MD.
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