Moles can differ by external appearance, size, localization, and changes over time. These very signs help the doctor determine whether observation is sufficient, whether there are indications for removing the formation and, if necessary, conducting a histological examination.
Depending on how deeply the cells of the mole are located in the skin, the following are distinguished:
- junctional nevi — the cells are located mainly at the border of the epidermis and dermis, therefore such moles more often look like flat pigmented spots;
- compound nevi — the cells are contained both at the border of the skin layers and deeper in the dermis, therefore the formation may be slightly raised above the surface;
- intradermal nevi — the cells are located mainly in the dermis, because of which the mole often has a convex shape and may be flesh-colored, light-brown, or brown.
By external appearance, moles can be:
- flat — located at the level of the skin;
- convex — rise above the surface and are more often injured;
- pigmented — have a brown, dark-brown, or almost black shade;
- weakly pigmented — may be light-brown, pink, or flesh-colored.
Benign moles usually have a symmetrical shape, even edges, uniform color, stable size, and do not cause discomfort.
| Sign | Usually benign mole | Signs for which a doctor's examination is necessary |
| Shape | Symmetrical | Asymmetrical |
| Edges | Even, clear | Uneven, blurred |
| Color | Uniform | Several shades |
| Size | Stable | Quickly increases |
| Sensations | Does not bother | Itches, hurts, bleeds |
The doctors of «Oxford Medical» recommend not assessing moles only by external appearance. Even a small formation should be shown to a dermatologist if it changes, bleeds, itches, or is often injured.