Two patterns catch most of it. ABCDE flags a mole that is Asymmetric, has a ragged Border, more than one Colour, a Diameter over about six millimetres, or is Evolving in any way. Applied whole, it flags a feature in eight or nine of ten melanomas, and Evolving does the most work 1. The ugly duckling is simpler: your moles rhyme with each other, so the one that looks unlike the rest is the suspect 2.
People who examined their own skin had roughly a two-thirds lower risk of dying from melanoma, a gap that held seventeen years on 3, and they caught their own tumours thinner 4.
Strip down in good light. You need a full-length mirror, a hand mirror, and a phone. Anchor it to a fixed monthly date so it survives.
Where you look depends on you. Fair skin, easy burns, red or blonde hair puts lifetime melanoma risk near one in thirty-three 5; men's tend to land on the back and trunk, women's on the legs. On darker skin melanoma is far rarer but shows up where the sun map ignores: soles, palms, between the toes, and the nail beds, where a new dark lengthwise band is the signal. If you have a hundred-plus moles, several odd ones, or a family history, add annual dermatology and ask about a one-time full-body photo baseline.
The fine print — when to skip it, and what people get wrong
ABCDE misses two. Nodular melanoma is often round, uniform, small; learn EFG instead — Elevated, Firm, Growing 1. Amelanotic melanoma has no colour: a pink papule that grows and won't heal.
Most skin cancers don't hurt. Waiting for pain or itch lets it grow. And sunscreen is prevention, not screening.
Two failure modes. Geography: the scalp, back, and soles get skipped, which is exactly where the dangerous ones hide; a hand mirror and a partner fix it. Memory: you can't recall a mole from six months back, so photograph and compare.
Also, don't over-react. Diagnoses have quintupled since 1975 while deaths barely moved, mostly thin harmless lesions 6. Book the appointment for something new, growing, or persistently changing past a month, not every spot you own.
- 1Tsao et al. (2015). Early detection of melanoma: reviewing the ABCDEs. Journal of the American Academy of Dermatology. link
- 2Grob JJ, Bonerandi JJ (1998). The "ugly duckling" sign: identification of the common characteristics of nevi in an individual as a basis for melanoma screening. Archives of Dermatology. link
- 3Berwick M, Begg CB, Fine JA, Roush GC, Barnhill RL (1996). Screening for cutaneous melanoma by skin self-examination. Journal of the National Cancer Institute. link
- 4Pollitt et al. (2009). Efficacy of skin self-examination practices for early melanoma detection. Cancer Epidemiology, Biomarkers & Prevention. link
- 5SEER (2024). SEER cancer stat facts: melanoma of the skin. link
- 6Adamson et al. (2024). Ecological study estimating melanoma overdiagnosis in the USA using the lifetime risk method. BMJ Evidence-Based Medicine. link
Skin Self-Examination
Five to ten minutes monthly — once muscle memory is built — with no recurring spend; first inventory pass runs longer. Partner involvement adds two minutes per side. The structural ask is sustained habit over decades, not in-the-moment difficulty.
Strong mechanistic chain (Tsao 2015 on ABCDE sensitivities; Gaudy 2017 on intrapatient comparative analysis raising specificity to 0.96) plus the foundational Berwick 1996 case-control and behavioural RCTs (Weinstock 2007; Robinson 2021) demonstrating that SSE training raises detection of atypical nevi and melanomas. No melanoma-mortality RCT; USPSTF I (USPSTF 2023). Worth doing on the basis of mechanism plus case-control; monitor for the overdiagnosis literature.
Mortality benefit signal rests on a single population-based case-control (Berwick 1996) reporting a 63% reduction in lethal melanoma among self-examiners, replicated at long follow-up (Paddock 2016); mechanism is unusually tight via Breslow-thickness-dominated prognosis (Gershenwald 2017). No mortality RCT exists and USPSTF gives skin screening an I statement (USPSTF 2023). Population mortality impact is real but modest at scale — concentrated in the 3-in-100 white-American lifetime melanoma incidence and the high-risk phenotypic subset.