Naevus (mole)

A nae­vus is a benign accu­mu­la­ti­on of pig­ment-forming cells in the skin. Most peo­p­le have bet­ween twen­ty and for­ty such moles. They can be pre­sent at birth or deve­lop later in life.

Cau­ses

Whe­ther and how many moles deve­lop is lar­ge­ly deter­mi­ned by gene­tic pre­dis­po­si­ti­on. UV radia­ti­on, espe­ci­al­ly sun­b­urn during child­hood, addi­tio­nal­ly pro­mo­tes their deve­lo­p­ment. Hor­mo­n­al pha­ses such as puber­ty or pregnan­cy can also chan­ge their appearance.

Sym­ptoms

Typi­cal are even­ly colou­red, shar­ply defi­ned brown spots or nodu­les with a sym­me­tri­cal struc­tu­re. The ABCDE rule helps with self-exami­na­ti­on: asym­me­try, irre­gu­lar bor­der, seve­ral shades of colour, dia­me­ter over five mil­li­me­t­res and ele­va­ti­on or chan­ge. A mole that cle­ar­ly dif­fers from all the others is also noteworthy.

Tre­at­ment

Incon­spi­cuous moles do not need to be remo­ved. Regu­lar skin can­cer scree­ning with a der­ma­to­scope is recom­men­ded, sup­ple­men­ted by digi­tal docu­men­ta­ti­on over time in cases of increased risk. Sus­pi­cious or bother­so­me moles are remo­ved com­ple­te­ly by sur­gery and exami­ned his­to­lo­gi­cal­ly; laser tre­at­ment alo­ne is not sui­ta­ble for pig­men­ted moles.

Rela­ted tre­at­ment at Swiss Der­ma Cli­nic: Skin can­cer scree­ning & mole checks