Moles are small skin growths that may appear flat or raised and are often tan, brown, black, reddish brown, or skin colored. They are typically about the size of a pencil eraser. There are three types of moles. Monthly skin self-exams are essential in the early detection of abnormal moles and melanomas.
Gary W. Cole, MD, FAAD
Gary W. Cole, MD, FAAD
Dr. Cole is board certified in dermatology. He obtained his BA degree in bacteriology, his MA degree in microbiology, and his MD at the University of California, Los Angeles. He trained in dermatology at the University of Oregon, where he completed his residency.
William C. Shiel Jr., MD, FACP, FACR
William C. Shiel Jr., MD, FACP, FACR
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
What are moles?
Besides being a small burrowing mammal and a unit of chemical weight, the term mole (in reference to skin) is used to describe a variety of skin imperfections. Personally, I prefer the term beauty mark. The medical term for mole is melanocytic nevus. Moles may be tan, brown, black, reddish brown, red, purple, or skin-colored and perfectly flat or raised. Most moles are the size of a pencil eraser (about 1/2 inch).
Certain moles become darker and more apparent with sun exposure and pregnancy. They typically lighten somewhat in the winter months. Moles can occur anywhere on the skin, including the scalp, ears, eyelids, lips, palms, soles, genitals, penis, and anal area.
A melanocytic nevus (plural nevi) is composed of masses of melanocytes, the pigment-producing cells of the skin. However, there are a variety of other skin lesions that are also mole-like. These include seborrheic keratoses, skin tags, dermatofibromas, lentigines, and freckles. In this article, the term moles will be synonymous with melanocytic nevus.
What causes moles, and what are risk factors for developing moles?
The genes we inherit from our parents, along with the amount of sun to which we are exposed (especially during childhood) are major factors in determining mole numbers. Skin with more sun exposure tends to have more moles. However, moles may also occur in sun-protected areas like the palms, soles, and genitals.
Both moles and freckles (medically termed ephelides) are darker than the surrounding skin. Moles may be raised, slightly raised, or completely flat while freckles are always totally flat. Freckles and "liver spots" (medically termed lentigines) are due to an increase in the amount of dark pigment called melanin. Moles are more common in people prone to freckles. Freckles are flat spots that are tan, slightly reddish, or light-brown and typically appear during the sunny months. They are most often found in people with light complexions. Many people with blond or red hair and green or blue eyes are more prone to these types of skin growths. Sun avoidance and sun protection, including the regular use of sunscreen may help to suppress the appearance of some types of moles and freckles.
Moles occur in all races (Caucasian, Asian, African, and Indian) and skin colors. Moles also are seen in animals.
Do babies get moles?
Yes. Moles may be present at birth or gradually appear later in the newborn period. Many children continue to develop moles through the teenage years and into young adulthood. Moles tend to grow very slightly in proportion to normal body growth. Congenital moles are moles present at birth and so must have been present during fetal development. Other moles may arise later as a result of factors that are not genetic but environmental, such as sun exposure.
Can I still get new moles as an adult?
Yes. While many moles arise in the first years of life, the total number of moles typically peaks in the second or third decade of life to an average of 35. Most people do not develop new regular moles after the age of 30. Adults often develop non-mole growths like freckles, lentigines, "liver spots," and seborrheic keratoses in later adulthood.
New moles appearing after age 35 may require close observation, medical evaluation, and possible biopsy. A brand-new mole in an adult may be a sign of an evolving abnormal mole or early melanoma. It is important to have any new or changing mole evaluated by a dermatologist.
What else could it be?
There are many mole simulators, including freckles, lentigines, liver spots, seborrheic keratoses, melanomas, neurofibromas, hemangiomas, skin tags, café au lait macules, and pigmented basal cell cancers. The optimal way to distinguish between these other growths is by consultation with a dermatologist, which may include a skin biopsy. Sometimes, a mole may occur adjacent to or on top of a non-mole growth like a freckle or seborrheic keratosis. When in doubt, a skin biopsy can be very helpful in diagnosis.
Medically Reviewed by a Doctor on 8/27/2014
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Moles - Risk Factors Question: What are your risk factors for developing moles? Briefly, describe your history and experience with moles.
Moles - Seborrheic keratoses Question: Are you prone to seborrheic keratoses? How do you have them treated?
Moles - Melanoma Question: If you have several moles, do you get checked regularly for melanoma? Please share your experience.
Moles - Skin Cancers Question: Have any of your moles been diagnosed as skin cancer? If so, what was the treatment?
Moles - Testing Question: Please discuss your experience with computerized mole-scan devices in identifying your mole types.
Moles - Types Question: What types of moles do you have?