Everyone has moles, sometimes 40 or more. Most people think of a mole as a dark brown spot, but moles have a wide range of appearances. Moles can arise anywhere on the skin, alone or in groups. They are usually brown in color and can be various sizes and shapes. The brown color is caused by melanocytes which are cells that produce the pigment melanin. Moles probably are determined before a person is born. Most appear during the first 20 years of a person's life, although some may not appear until later in life. Sun exposure increases the number of moles.
Each mole has its own life cycle of growth. At first, moles are flat and tan, pink, brown or black in color. Over time, they usually enlarge and some develop hairs. As the years pass, moles usually change slowly, becoming more raised and lighter in color although some will not change at all. Most moles will slowly disappear, seeming to fade away. Others will become quite raised off the skin where they may get irritated by rubbing. This is the typical life cycle of the common mole which occurs over about 50 years.
Moles may darken with exposure to the sun. During the teen years, with birth control pills and pregnancy, moles often get darker and larger and new ones may appear.
Recent studies have shown that certain types of moles have a higher-than-average risk of becoming cancerous. Moles are present at birth in about 1 in 100 people. They are called congenital nevi. These moles may be more likely to develop a melanoma than moles which appear after birth. When a congenital nevus is more than eight inches across, it poses the greater risk for developing melanoma. Moles known as dysplastic nevi or atypical moles are larger than average (usually larger than a pencil eraser) and irregular in shape. They tend to have uneven color with dark brown centers and lighter, sometimes reddish, uneven borders or black dots at the edge. These moles often run in families. Persons with dysplastic nevi may have a greater-than-average chance of developing malignant melanoma. People with many more moles than average (greater than 100) are also more at risk for melanoma.
These people should be seen regularly by a dermatologist to check for any changes that might indicate skin cancer. They should also learn to do regular self-examinations, looking for changes in the color, size or shape of their moles or the appearance of new moles. They should also shield their moles from sun exposure using sunscreen and clothing.
The majority of moles and other blemishes are benign. Spots or blemishes that warrant medical concern are those that act differently from other existing moles. This includes any spot that changes in size, shape or color, or one that bleeds, itches, becomes painful, or first appears when a person is past twenty. A mole may become a melanoma. Therefore, it's best to get medical advice if you notice a mole that does not follow the normal pattern. A dermatologist may be able to tell if the mole is harmless or may elect to remove it and have it analyzed under a microscope.
A person may wish to get rid of moles that are irritated by clothing or simply because they are unattractive. The most common methods of removal include numbing the area and shaving the mole off or cutting out the entire lesion and stitching the area closed.