Changes in Moles

A skin mole is an abnormal collection of pigment cells (known as melanocytes) which are present in the basal layer of the epidermis of the skin. A mole can develop anywhere on the skin and it can be of any shape and size. Sometimes, moles also sprout hair. Usually, moles are brown in color but skin-colored moles are also observed in a few cases. Brown color of the mole is caused by a natural body pigment known as melanin, which is produced by the special cells called melanocytes. Melanin protects us from the harmful effects of the ultra violet rays of the sun. Moles which are present on the body from birth are known as congenital melanoma nevi. Some moles may disappear with age, whereas some remain throughout the life of an individual. Moles change according to the changes in hormonal levels in women and may first appear, enlarge, or darken during pregnancy. Presence of moles does not cause any serious problem. But when there are sudden changes in the shape, size and color of the mole, it is advisable to get a biopsy done.

It is very difficult to check each and every mole present on the skin regularly. Some moles show signs like bleeding, itching, fluid oozing, inflammation, broken skin or irritation. These moles need to be checked immediately by a dermatologist. Moles, which are irregular in shape and larger than average (larger than a pencil eraser) are known as dysplastic nevi or atypical moles. They may have uneven color, with dark brown centers and sometimes reddish, uneven border or black dots at the edge. These moles are often hereditary. People who have dysplastic nevi have more chances of developing malignant melanoma, which is a form of skin cancer and can be fatal. It develops as a dark, fast-growing spot which changes its shape, size and color; and leads to reddening, itching and bleeding. Therefore, one should visit a dermatologist to check if there are any indications of skin cancer. If melanoma is treated at an early stage, it can be cured. People who have a family history of malignant melanoma should learn to do regular self-examination.Those who have more than 25 moles have a greater possibility of developing melanoma. Exposure to sunlight causes a change in dysplastic nevi and increases its growth. Halo nevi is a kind of mole, which is commonly observed in children and young adults. The mole is surrounded by a white ring; the skin becomes white due to the loss of melanin. There are a few other types of moles, like blue naevus, a deeply rooted blue-colored mole, observed in West Indian infants; and juvenile melanoma (Spitz nevus), it similar to melanoma, a condition, where the pigment cells form a benign tumor, which is pink-brown in color.

There are some ABCD parameters summarized by the American Cancer Society, to check whether a mole is suspicious. They are Asymmetry, Border, Color and Diameter.

• Asymmetry: Half of the mole does not match with the appearance of the other half
• Border: The border is either ragged, notched or blurred and uneven.
• Color: The color of the mole is not uniform, different shades of color like red, white, black, blue, brown are present.
• Diameter: The diameter is greater than 1/4 inch, that is 6 mm

Moles can be removed by excision surgery, electro surgery, cauterization (which involves coagulation of blood and destroying the tissue with a hot iron or caustic agent or by freezing) or cryosurgery (a surgery done to destroy unwanted tissues using extreme cold, usually liquid nitrogen). But, all these methods are painful and require anesthesia. After the removal of dangerous moles, skin mole growth can be prevented by avoiding exposure to excessive sunlight.