Blue Nevus grabs your attention because it can look very similiar to melanoma.
What are the clinical features?
A blue nevus is usually raised and looks like a dome. It can be dark blue to almost black in colour.
Occasionally, a melanoma may look very similar to this type of mole (See photograph).
There are many places on the body where blue nevi can develop; however, they are usually isolated. This means you are unlikely to see more than one nevus in one area. The most common places on the body for blue nevi to occur is the face, neck, hands, feet, scalp and buttocks.
Blue nevi typically exhibit the following characteristics:
- An oval or round shape
- Small in size
- Appearance: smooth
- a flat or elevated surface
- a diameter of around 1-5 mm
A blue nevus should be positively identified every time by your doctor to confirm that it’s not a melanoma.
Gallery of Blue Nevi
Please click on the images for details.
What is the significance?
The Blue nevus is a harmless mole that is typically not problematic. A benign blue nevus can remain on your skin your entire life and stay unchanged.
However, you should check with your doctor if any of these changes occur:
- It becomes asymmetrical in shape
- Have a rough edge
- Notice a change in colour
- Grows in size or reaches a diameter of 6 mm or more
- Becomes painful
Often, your doctor can diagnose a blue nevus just by looking at it, but they may also recommend a biopsy.
What is the Treatment for this Mole?
Once your doctor has confirmed that you have a blue nevus, no treatment is required.
A blue nevus may be removed surgically if your doctor is concerned about the nature of the lesion, if you have cosmetic concerns, or the mole is causing discomfort. In these cases, the mole can be cut out completely or shaved away using a surgical knife by your doctor.
These are some of the key terms that you may find when you’re given a pathology report on this blue mole.
Blue nevus moles are formed similarly to other moles. The dark colour is due to the gathering of melanocytes n nests. These are cells that produce melanin and influence skin colour.
The melanocyte nests of the blue naevus are found deep in the dermis, giving these moles a dark blue colour.
Common Blue Nevus
There are several different types of Blue Nevus but it’s not possible to distinguish the different types without a biopsy. However, you probably won’t need a biopsy unless your doctor suspects melanoma or when your skin exam fails to definitively identify a suspicious mole as a blue nevus.
The common blue nevus is the most common type of blue nevus. It’s often found on the back of the hands/feet, the head, neck and lower back.
Cellular Blue Nevus
The Cellular blue nevus is a less common type of Blue Nevus with abnormal cells.
The cellular blue nevus is often more nodular (raised) than a common blue naevus, and is often larger as well (eg. 1 to 3cm in diameter). You will find them most often on the lower back or buttocks but sometimes on the backs of the hands or feet.