Category: Illness or disabilities
Introduction and description
A mole is a growth on the skin that develops when pigment cells (melanocytes) grow in clusters.
Another name for a mole is a nevus. The plural is nevi.
Freckles, in contrast, are clusters of concentrated melaninized cells.
Freckles do not have an increased number of the melanin-producing cells melanocytes, but instead have melanocytes that overproduce melanin granules (melanosomes) changing the coloration of the outer skin cells called (keratinocytes). As such, freckles are different from moles.
There are two main types of mole:
- A common mole - is usually smaller than about 5 millimeters wide (about 1/4 inch, the width of a pencil eraser). It is round or oval, has a smooth surface with a distinct edge, and is often dome-shaped. A common mole usually has an even colour of pink, tan, or brown. People who have dark skin or hair tend to have darker moles than people with fair skin or blonde hair. Several photos of common moles are shown here
- A dysplastic nevus - is a type of mole that looks different from a common mole. It may be bigger than a common mole, and its colour, surface, and border may be different. It may be more than 5 millimeters wide, may have a mixture of several colours, from pink to dark brown. Usually, it is flat with a smooth, slightly scaly, or pebbly surface, and it has an irregular edge that may fade into the surrounding skin. Some examples of dysplastic nevi are shown here.
Neither Common moles or Dysplastic moles are cancerous, neither should they be thought of as an illness, a disease or a disability, but moles can be the focal point when skin cells become cancerous.
Most dysplastic nevi do not turn into melanoma. Most remain stable over time and a common mole only rarely turns into a melanoma, but we have provided this section so that you can look for the signs and symptoms.
What is melanoma?
Melanoma is covered in more detail in the section devoted to the illness, but briefly Melanoma is a type of skin cancer that begins in melanocytes. It is potentially dangerous because it can invade nearby tissues and spread to other parts of the body, such as the lung, liver, bone, or brain. The earlier that melanoma is detected and removed, the more likely that treatment will be successful.
Most melanocytes are in the skin, and melanoma can occur on any skin surface. It can develop from a common mole or dysplastic nevus, and it can also develop in an area of apparently normal skin. In addition, melanoma can also develop in the eye, the digestive tract, and other areas of the body. It can even be found under the fingernails, under the toenails, on the palms of the hands, or on the soles of the feet. This shows that melonomas are not just sun related and this is explored in the section on Melanoma.
When melanoma develops in men, it is often found on the head, neck, or back. When melanoma develops in women, it is often found on the back or on the lower legs.
The actress Anne Curtis has a lot of moles and has decided to undergo annual tests to ascertain she is clear of cancer.
These are the symptoms to watch for:
- Increase or large number of dysplastic moles - the chance of melanoma is about ten times greater for someone with more than five dysplastic nevi than for someone who has none, and the more dysplastic nevi a person has, the greater the chance of developing melanoma.
- The colour changes or is uneven - Shades of black, brown, and tan may be present. Areas of white, grey, red, pink, or blue may be seen
- Border that is irregular - The edges may be ragged, notched, or blurred in outline. The pigment may spread into the surrounding skin.
- Hardness and texture - The skin on the surface becomes dry or scaly and/or the mole becomes hard or feels lumpy
- Inflammation and bleeding - It starts to itch and/or it bleeds or oozes
- Noticeable and evolving change - The mole has changed over the past few weeks or months such that it is noticeable. For example a noticeable increase in size or shape or colour. Melanomas can be tiny, but most are larger than 6 millimeters wide (about 1/4 inch wide).
How is melanoma diagnosed?
The only way to diagnose melanoma is to remove tissue and check it for cancer cells. The doctor will remove all or part of the skin that looks abnormal.. The sample will then be sent to a lab and a pathologist will look at the tissue under a microscope to check for melanoma.
Moles do not need treating because they are not an illness, disease or disability, but Melanoma does.
References and further reading
The photos on this page came from the National Cancer Institute NCI's What Does a Mole Look Like?