[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Clinical exam](https://durgical.com/en/clinical-exam/) › [Skin, head and neck](https://durgical.com/en/clinical-exam/#a-head_neck) › The ABCDE of pigmented lesions [Clinical exam](https://durgical.com/en/clinical-exam/) · [Skin, head and neck](https://durgical.com/en/clinical-exam/#a-head_neck) # The ABCDE of pigmented lesions - Sign Five features of a mole (asymmetry, border, colour, diameter and evolution) that raise suspicion of melanoma and call for assessment. Updated 2026-11-01 **See it in 3D:** [Skin](https://durgical.com/en/anatomy/skin/) ## Key points - A asymmetry, B irregular border, C several colours, D over 6 mm, E evolution or change. - Evolution (E) is the most important criterion. - Nodular and amelanotic melanoma may not fit the rule: raised, firm and growing is suspicious. - The 'ugly duckling' sign: the mole that looks unlike the patient's other moles. - Pigment spreading from the nail onto the nail fold (Hutchinson sign) suggests subungual melanoma. - Prognosis depends on thickness (Breslow): early detection changes the outcome. ## What it is The ABCDE is a screening rule for deciding which pigmented lesion deserves a closer look for possible melanoma. Each letter is a feature: Asymmetry, irregular Border, varied Colour, Diameter over 6 mm and Evolution (change). It does not diagnose; it selects lesions for dermoscopy or biopsy. The E (change over time) is the most valuable feature. ## The anatomy it tests - Melanoma arises from the melanocytes of the epidermal basal layer, which make melanin. - Disordered growth gives irregular pigment (C) and asymmetric spread (A, B); it first spreads sideways, then invades down into the dermis. - Invasion depth (Breslow thickness), measured on biopsy, is the main prognostic factor, which is why finding it while thin matters. ## How to elicit it - Examine the whole skin in good light, including scalp, soles, palms, nails, web spaces and genitals. - Ask whether any mole is new, has changed in size, shape or colour, itches, bleeds or crusts. - A: draw an imaginary line through the centre of the lesion and compare whether the two halves match in shape and colour. - B: look at the border: irregular, notched, blurred, or pigment fading into the surrounding skin. - C: count the shades: more than one colour (brown, black, red, white, grey or blue) is suspicious. - D: measure the longest diameter with a ruler; over 6 mm is suspicious, though smaller melanomas exist. - E: compare with earlier photos or records and look for the lesion that differs from the patient's other moles (the 'ugly duckling'). - Check the nails: a new or widening longitudinal pigmented band, or pigment spreading onto the nail fold, is suspicious. ## What a positive result means - Positive: a lesion with one or more features, above all recent change, is suspicious and referred for dermoscopy and possible biopsy. - E outweighs the other letters: a mole that changes, grows, bleeds or ulcerates is suspicious even if small. - Nodular melanoma often fails the ABCD: it is a raised, firm, fast-growing lesion, sometimes without pigment. - Acral lentiginous melanoma (palms, soles, nails) is proportionally more common in people with dark skin and is often found late because nobody looks. - A negative ABCDE does not exclude melanoma: there are small, symmetric or non-pigmented (amelanotic) melanomas. ## Usefulness and limits - It is a sensitive but not very specific screening rule: many benign atypical naevi meet some letter. - Dermoscopy in trained hands is more accurate than naked-eye inspection. - Diagnosis is confirmed only by biopsy and histopathology. ## Memory aid If a mole 'behaves differently' (changes or does not look like its siblings), look twice even if it is small. ## Test yourself Think of the answer, then tap the question to see it. ## What does each letter of the melanoma ABCDE stand for? Asymmetry, irregular Border, varied Colour, Diameter over 6 mm and Evolution (change in size, shape, colour or symptoms). ## Which ABCDE criterion is considered the most valuable? E: change over time. A mole that grows or changes is suspicious even if under 6 mm. ## Which type of melanoma often fails the ABCD criteria? Nodular melanoma (and amelanotic melanoma): a raised, firm, fast-growing lesion, sometimes without pigment. ## Where does acral lentiginous melanoma appear and why examine those sites? On palms, soles and nails; it is proportionally more common in dark skin and is diagnosed late because those sites are not checked. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/clinical-exam/the-abcde-of-pigmented-lesions/) ## See it in 3D The structures of Durgical's 3D anatomy where it is found. - [Skin](https://durgical.com/en/anatomy/skin/) ## Related - [Skin examination: primary and secondary lesions](https://durgical.com/en/clinical-exam/skin-examination-primary-and-secondary-lesions/) - [Digital clubbing and nail signs](https://durgical.com/en/clinical-exam/digital-clubbing-and-nail-signs/) - [Lymph node examination](https://durgical.com/en/clinical-exam/lymph-node-examination/) ## Related conditions - [Melanoma](https://durgical.com/en/conditions/melanoma/) - [Basal cell carcinoma](https://durgical.com/en/conditions/basal-cell-carcinoma/) - [Cutaneous squamous cell carcinoma](https://durgical.com/en/conditions/cutaneous-squamous-cell-carcinoma/) [← All of the clinical exam](https://durgical.com/en/clinical-exam/) Educational content on the clinical exam; it is learned and practised under supervision. It does not replace assessment by a health professional and is not for self-diagnosis. Sources: [What Does Melanoma Look Like? - NCI](https://www.cancer.gov/types/skin/melanoma-photos) (National Cancer Institute, 2026); [Description of Skin Lesions - Dermatology - Merck Manual Professional Edition](https://www.merckmanuals.com/professional/dermatologic-disorders/approach-to-the-dermatologic-patient/description-of-skin-lesions) (Merck Manuals, 2026); [Nail abnormalities: MedlinePlus Medical Encyclopedia](https://medlineplus.gov/ency/article/003247.htm) (MedlinePlus, U.S. National Library of Medicine, 2026). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/clinical-exam/the-abcde-of-pigmented-lesions/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/clinical-exam/the-abcde-of-pigmented-lesions/