ABCD Mole Check & Skin Cancer Screening in London
The ABCD rule is a simple method to help identify suspicious moles that may need medical review. It stands for Asymmetry, Border, Colour, and Diameter — four key changes that may signal early skin cancer. At Skinhorizon, our consultant dermatologists offer detailed mole checks and dermoscopic assessment to ensure accurate diagnosis and peace of mind.
Call Us Book ConsultationWhat is the ABCD Mole Check?
The ABCD rule is an easy-to-remember tool designed to help identify suspicious moles that may require specialist assessment. It focuses on four important warning signs: Asymmetry, Border irregularity, Colour variation, and Diameter.
Why it matters
Melanoma, a type of skin cancer, can often be detected early through mole changes. Identifying unusual features early improves the chances of successful treatment. The ABCD mole check is not a substitute for professional diagnosis but serves as a vital first step in recognising potential skin cancer.
Understanding the ABCD rule
- A – Asymmetry: One half of the mole looks different from the other half.
- B – Border: Irregular, scalloped, blurred, or poorly defined edges.
- C – Colour: Multiple shades (brown, black, red, white, or blue) within a single mole.
- D – Diameter: Moles larger than 6mm, or any that are growing in size.
When to see a dermatologist
Seek professional review if you notice any of the ABCD signs, or if a mole changes in size, shape, colour, or begins to itch or bleed. Dermatologists use dermoscopy to examine moles in detail and determine whether removal or biopsy is needed.
Why choose Skinhorizon?
- Consultant dermatologist-led mole checks using dermoscopy.
- Quick, same-day appointments available.
- Comprehensive mole mapping and digital photography on request.
- CQC-regulated clinic for safe and professional care.
Your first visit — what to expect
- History: Discussion of personal and family history of skin cancer.
- Examination: Visual and dermoscopic inspection of moles.
- Diagnosis: Identifying suspicious features using the ABCD criteria.
- Treatment plan: Reassurance, monitoring, or mole removal if indicated.
- Follow-up: Advice on self-checks, sun protection, and routine monitoring.
Reviewed by: Dr Mohammad Ghazavi, Consultant Dermatologist
Skinhorizon Clinic, 4 Clarendon Terrace, Maida Vale, London W9 1BZ
Last reviewed: 21 August 2025
Concerned about a changing mole? Get peace of mind with a consultant-led mole check today.
Call Us Book ConsultationABCD Mole Check FAQs
What does the ABCD rule stand for?
ABCD stands for Asymmetry, Border, Colour, and Diameter — key features to look for when checking moles.
Does every mole with ABCD features mean skin cancer?
No, not all abnormal-looking moles are cancerous. However, the ABCD rule helps identify suspicious moles that need professional review by a dermatologist.
What other signs should I look out for?
Moles that itch, bleed, become crusty, or change rapidly in size, shape, or colour should be assessed by a dermatologist — this can help detect melanoma and other skin cancers early.
How often should I check my moles?
Monthly self-checks and yearly professional mole reviews are recommended, especially for those with many moles, fair skin, or a family history of skin cancer.
Is mole mapping useful?
Yes, mole mapping with digital photography helps monitor changes over time and detect suspicious lesions earlier.
What happens if a mole looks suspicious?
The dermatologist may recommend dermoscopic monitoring, removal, or biopsy to confirm diagnosis and ensure early treatment if needed.
