7 Warning Signs a Mole Should Be Checked
An expert guide by Mr Etienne Raffner — understanding the ABCDE rule and when to seek professional assessment for suspicious moles.
About the Author
Mr Etienne Raffner is a Specialist Grade Maxillofacial and Oral Surgeon and Clinic Director at The Oving Medical Clinic. He is Course Lead in Surgical Dermatology at VRiMS and a core member of the Kent and Sussex Skin Cancer MDT, specialising in the full spectrum of skin lesion management and surgical dermatology.
As a specialist maxillofacial and oral surgeon and core member of the Kent and Sussex Skin Cancer MDT, I see patients across the full spectrum of skin lesion management — from straightforward reassurance to complex surgical excision and reconstruction. A significant part of my practice involves assessing lesions of the head, neck and face, where early identification of concerning changes is particularly important.
One of the most common questions I hear is: "How do I know whether a mole is something I should worry about?"
The honest answer is that most moles are completely harmless. The majority of adults have between 10 and 40 moles across their body, and the vast majority never cause problems. But changes to a mole can sometimes signal premalignant change or skin cancer — including melanoma, the most serious form. What matters is knowing what to look for, and acting promptly when something changes.
What Is a Mole?
A mole is a cluster of pigment-producing cells called melanocytes. They can appear anywhere on the body and vary considerably in colour, shape and size. Some people are born with moles; others develop them through childhood and into early adulthood.
Most moles are entirely harmless and remain unchanged for many years.
The key thing to watch for is change.
The ABCDE Rule
Medical professionals use the ABCDE rule when assessing moles. It is a useful framework for patients too.
Asymmetry
Healthy moles tend to be symmetrical. If you draw a line through the centre of a normal mole, both halves should look broadly similar. A mole that has become noticeably uneven may warrant further investigation.
Border
Benign moles generally have smooth, well-defined edges. A suspicious mole may have irregular, blurred, notched or scalloped borders — sometimes described as 'jagged edges'. These changes can indicate abnormal cell growth at the margin.
Colour
Most benign moles are a single consistent colour. Warning signs include multiple shades within the same mole, black patches or sudden darkening, red or white areas, or blue or grey pigmentation (sometimes referred to as a 'blue veil'). Any significant variation in colour should be assessed professionally.
Diameter
As a general guide, moles larger than 6mm are worth closer attention. However, size alone is not a reliable indicator — some melanomas are considerably smaller. Any mole that is steadily increasing in size should be checked, regardless of its current measurement.
Evolution
This is arguably the most important factor. If a mole changes in any way — size, shape, colour, elevation or texture — it should be assessed by a qualified clinician. A mole that has looked the same for years and then starts to change is the key red flag.
Additional Warning Signs
Beyond the ABCDE framework, several other symptoms should never be dismissed.
Bleeding or Crusting
A mole that repeatedly bleeds, scabs or crusts over without any obvious injury should be examined promptly.
Persistent Itching
Occasional irritation is usually harmless, but persistent itching in or around a mole can indicate underlying cellular changes.
Pain or Tenderness
Normal moles are painless. A mole that becomes sore or tender deserves professional assessment.
Rapid Growth
Any skin lesion that develops quickly over weeks or months should be seen by a clinician.
'Ugly Duckling' Sign
If you have multiple moles and one looks noticeably different from all the others — in colour, size or shape — it is worth having it assessed. This 'odd one out' appearance is a recognised clinical prompt for further evaluation.
Who Is Most At Risk?
Certain factors increase the risk of developing skin cancer. These include:
- •Fair skin, or a tendency to burn rather than tan
- •A history of frequent or severe sunburn
- •Prolonged or cumulative sun exposure
- •Use of sunbeds
- •A family history of melanoma
- •A large number of moles, particularly those with an irregular appearance
- •A personal history of skin cancer
Important: Skin cancer can develop in anyone, regardless of skin type, age or background.
What Happens During a Mole Assessment?
Many patients delay booking an appointment out of concern about what the assessment might involve. In practice, a mole consultation is typically quick, straightforward and non-invasive.
A consultation typically includes:
A review of your medical history and relevant risk factors
Clinical examination of the lesion
Dermatoscopic assessment using specialist magnification equipment
A clear explanation of findings with dermatoscopic imaging
Discussion of recommended next steps
The majority of moles assessed in this way prove entirely benign and require only monitoring or reassurance. Where a lesion does appear suspicious, I can discuss removal and histological analysis — carried out to the same standards applied within the regional skin cancer MDT.
When Should You Seek Advice?
If you have noticed a new mole, or any change in an existing one, it is sensible to arrange an assessment sooner rather than later. Most suspicious moles ultimately prove harmless — but the reassurance that comes from professional assessment is itself valuable, and early detection remains one of the most effective tools in managing skin cancer successfully.
If you have concerns about a mole, skin lesion or pigmented area, please do not hesitate to contact the clinic. When it comes to skin cancer, early assessment is always the right approach — and early diagnosis can be lifesaving.
Book Your Mole Assessment
Contact us to arrange a professional mole assessment with Mr Etienne Raffner at Oving Medical Clinic.
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