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Different Types of Moles

  • Moles can signal one of the first signs of skin cancer, or potential skin cancer warning signs
  • Congenital nevi and dysplastic nevi are among the highest skin cancer risk factors when it comes to moles because they incur an increased potential for the development of melanoma skin cancer
  • Skin cancer awareness and early skin cancer detection are the means to helping prevent skin cancer from cancerous moles


Almost everyone has at least one mole somewhere on their skin. On average, a person will have between 10 and 40 different moles. You may even develop new moles as time passes. The good news is that the majority of moles on your skin are not going to be harmful or cancerous. However, understanding more about the types of moles and about recognizing when they may be causing you a problem can help you take quick action when necessary.

Causes of Moles

Moles (called nevi in doctor terminology) are actually skin growths caused by clusters of melanocytes. Melanocytes are the types of skin cells which produce melanin – the chemical responsible for giving your skin color. Higher concentrations of melanin result in a darker color. When these cells cluster together, they release larger amount of melanin in that area which causes the skin color changes.

Two Types of Moles

Moles are classified in different ways but two types run an especially high risk of leading to melanoma skin cancer later in life. The first type are the congenital nevi. These moles are present on the skin from birth. About 1% of the population are born with congenital moles. If you’re one of them, keep a close eye on those moles because they are more likely to become cancerous.

The second type of potentially dangerous moles are the dysplastic nevi. Also sometimes referred to as atypical, these moles are recognized by their large size. Keep in mind that the average mole should be smaller than a pencil’s eraser. Anything larger would fall into this category. Dysplastic nevi also lack the even borders which characterize normal moles. In general, people who have this type of mole have many moles – sometimes as many as 100. They are often see in families and should be watched carefully because of their higher risk for becoming cancerous.

Signs of Cancerous Moles

If you have either congenital or dysplastic nevi, you should definitely learn the five signs of a potentially cancerous mole. The acronym ABCDE is used to describe these signs: asymmetry, irregular border, color changes, larger diameter, and evolving appearance. You should make a point of checking all of your moles at least once a month so you can catch these signs as early as possible.

Although skin cancer does have the lowest fatality rate of any type of cancer, cancerous moles lead to melanoma which is the most dangerous of the three types of skin cancers. Early treatment can prevent the cancer from spreading and can reduce your risk of further complications.

Even if you don’t have either of the high-risk types of moles, you should still regularly check them and their appearance to ensure skin cancer doesn’t creep up on you.

Treating Moles

Normally, non-cancerous moles are not treated. They don’t pose any type of health threat and are usually so small they are not visually problematic. However, if you do have a mole that could be cancer-related your physician will refer you to a dermatologist who will remove some or all of the mole to check for cancer growth. If the mole is found to be cancerous, your dermatologist may check the surrounding tissue for signs it has spread and/or may recommend a round of cancer treatment, such as radiation, to kill any further cancer cells in the area.

The information supplied in this article is not to be considered as medical advice and is for educational purposes only.

One Response to “Different Types of Moles”

  1. 1
    Keith M. Says:
    It's good to know that skin cancer is the least dangerous type of cancer, because I've got a lot of moles. So, what exactly would happen if one of them turns cancerous? Would they just remove it or is it more complicated than that? If the cancer spreads, then do they have to remove all the affected skin?