Dark brown moles first appear on the skin during childhood and early adulthood. People with lighter skin tend to have more moles, with the average ranging from 10 to 40, according to the American Academy of Dermatology (AAD). While most moles are harmless, some moles may become cancerous and must be removed.
Identification
Moles, or nevi, develop when pigmented cells cluster together on the skin. Moles vary in size and shape, but the American Academy of Osteopathic Dermatology reports that most moles are less than ¼-inch in size. Moles can be flat or raised, may appear in groups and can appear anywhere on the skin.
Types
Acquired moles are the type of moles that appear after birth, while congenital moles are present from birth. Atypical moles are not perfectly round and are larger than average moles. These moles may not be uniformly brown, but may contain areas of red, pink, brown or tan.
Detecting Cancerous Moles
When moles become cancerous, melanoma, a type of skin cancer, occurs. Pre-cancerous or cancerous moles usually look different from the usual brown round or oval mole. Performing a skin self-exam can help you spot changes in your moles that may indicate cancer. Self-exams can be conducted with the aid of a mirror or with the assistance of another person who will examine the moles on your back or in other areas. Questionable moles are those that are asymmetrical and those with borders that are irregular or scalloped. Mole color should be uniformly brown with no color variations. Moles that are larger than a pencil eraser can be a reason for concern, particularly if the moles were not always so large.
Risk Factors
Certain types of moles may increase your risk of developing cancer. Having a large congenital mole or more than 50 to 100 acquired moles can put you at a higher risk of developing melanoma, according to the AAD. The presence of atypical moles may also increase the skin cancer risk.
Mole Removal
Doctors remove moles if the mole appears abnormal or if the patient wants the mole removed for cosmetic reasons. Large moles are removed by excising, or cutting, the mole from the skin and stitching the area closed. If the mole is small, the doctor may shave the mole from the skin with a surgical blade. Very large moles are removed in stages and require several office visits for complete removal. After removal, the mole is sent to a laboratory, where it is tested for cancer.
Warning
The AAD cautions against trying to shave off a mole at home. If the mole is cancerous, the cancer can spread because some cells may remain after shaving. When potentially cancerous moles are removed in a doctor's office, they are excised no matter the size to ensure that all of the cells are removed.
