Junctional naevi are so called because the cells of which they arecomposed are situated at the junction of the epidermis and dermis. They are flat, mid to dark brown moles which first appear in childhood. The number of potentia moles an individual has seems to be genetically predetermined, but it also seems that sun exposure provokes their actual appearance on the skin.



It is not necessary to have all your junctional naevi removed. In the main they are harmless blemishes, although it is recognised that they have some potential to develop into melanoma. It should be stressed that this risk of conversion to melanoma is extremely low. It is certainly not appropriate -or practical-to remove all these moles just because of the very small risk, especially as we know that melanomas also develop in normal skin and not only in moles.

Compound naevi are moles in which the pigmented cells are located at the junction of the epidermis and dermis and also in the dermis. Thus these often have a two-tone character with a raised central area, the part in the dermis, and a surrounding flat area, the part at the junction. When the component in the dermis matures, which it may do with time, people may notice that the mole is becoming raised.This often prompts them to see their doctor to have the moles checked. Such a check is wise, although the change is not a sign of melanoma in this case.

In intradermal naevi, all the pigmented cells are situated in the dermis. They have lost their potential to change and are totally benign moles. With time they may lose their colour, and become soft like skin tags. Treatment is only required for cosmetic reasons if desired by the patient.

Dysplastic naevi are junctional or compound naevi which have some irregular features, both on the surface of the skin and on examination under the microscope. Many people just have one or two dysplastic naevi and this is not associated with an increased risk of melanoma. However, there is a very rare situation in which virtually all family members have many dysplastic naevi and these people have a very high risk of melanoma. People who have a few dysplastic naevi are often photographed and checked regularly to make sure that melanoma does not develop in any of their moles. It is not appropriate to remove all the moles because melanomas more often arise in normal skin, as mentioned above.

It takes training and experience to be able to distinguish one type of mole from another. If you have any concerns about your moles it is worth asking your doctor or dermatologist for advice-it beats worrying unnecessarily!