What is a congenital nevus?


A congenital nevus (plural nevi) is a medical term for a mole found on an individual since birth. This is an extremely common birthmark which occurs in around 1% of all new-borns. Most of these are relatively small (less than 1.5 cm). In some cases, the nevus can be bigger than the size of an outstretched palm, or even large parts of the torso and have excessive hair growth on the surface. A nevus larger than an outstretched palm is usually considered “Large”, while one which covers much of the torso is considered “Giant”.

Why remove them?

In most cases, congenital nevi are harmless by nature and will not affect the daily lives of an individual. However, many might want to remove them for aesthetic reasons, especially they are unusually large, hairy or located at conspicuous places such as the face.

Although rare, individuals with congenital nevi, especially large ones, have a slightly increased risk of melanoma, a type of skin cancer occurring in pigment producing cells. Hence, it might be wise to remove some moles, especially the larger ones to reduce the risks of melanoma.

Congenital melanocytic nevus (Cancerous moles)

As congenital nevi are atypical agglomerations of pigment cells on the skin, it presents an increased risk of developing melanoma than individuals without them. If you are worried about a potentially cancerous nevus, the “ABCDE rule” listed below can be a quick and rough guideline:

Asymmetry: Irregular shape (if a line is drawn down its middle, both halves look different and would not match each other)
Border: Edges are not well-defined and tend to be uneven, which fades into the surrounding skin
Colour: No uniform colour throughout
Diameter: Bigger than ¼ inches (~6mm) across
Evolution: Changes in shape, colour, size, surface or symptoms over time (becoming itchy, painful or begins to bleed)

The more “ABCDE” characteristics your congenital nevus have, there more likely it is to be a cancerous one. However, even nevi that check all 5 on the list can be a benign one. You should always consult a doctor if you are worried that you may have a cancerous mole. At Clifford, our experienced doctors are able to check the mole for you and remove them.

Methods of removal

1. Laser treatment

Laser treatment is usually second in line if topical treatment is deemed to be ineffective. The pigment molecules in the mole is broken down using a medical laser specifically designed for this purpose. Slight effects can be seen after one session, but multiple sessions are usually required to remove the mole completely.

2. Shaving excision

This is the least invasive out to the surgical methods of congenital nevus removal. Most surface level and minor raised nevi can be removed by carefully shaving it down using a sharp surgical scalpel or razor. The scar from shaving excision is usually less noticeable, and wounds typically heal in about 1 to 2 weeks after the superficial scab falls off. Unlike laser and topical treatments, surgical excision methods produce results immediately, after the wounds heal.

3. Cutting excision

For congenital nevi which are large, highly elevated, have deep roots or potentially cancerous, cutting excision is usually required as it is the most complete removal method by far. The entirety of the nevus is cut out with a scalpel or surgical scissors, and the remaining skin is stitched up. Cutting incision is the most invasive, but the mole also has the least chance of recurrence.


What are the differences between the different methods of mole removal?

Type of removal Topical treatment Laser treatment Shaving excision Cutting excision


Lowest ------------------------------------------------------------------------- Highest
Suitable for Small, surface level moles Small, surface level moles Small to medium surface level or mildly raised moles Large, highly elevated, deep-rooted or potentially cancerous moles
Results seen After several sessions After several sessions Immediately Immediately


Lowest ------------------------------------------------------------------------- Highest
Possibility of recurrence Lowest ------------------------------------------------------------------------- Highest 

Is the procedure painful?

Topical or local anaesthesia will be administered as required for all treatments so there will be minimal discomfort.

Is there any downtime?

There will be minimal downtime for all treatment types.

Mild redness may be expected after topical and laser treatment, which will usually subside in a few hours

Shaving and cutting excisions will leave visible wounds, but these are usually indistinguishable from general wounds, and will heal in about 1 to 2 weeks.

Are there any side effects/possible complications?

Side effects from congenital nevus removal are rare, and patients usually recover completely without complications.

Some individuals with sensitive skin may react excessively to topical and laser treatment. Please contact our doctor immediately if severe skin irritation occurs

Inflammation and Infection may occur in surgical excision methods, but these can be avoided with good post-care.

What should I take note of after the procedure?

Follow the post-care instructions given by the doctor closely to minimise the risks of infection. The doctor may also prescribe some post-care antibiotics and antiseptic to help with this.