Freckle or Melanoma? How to Tell Them Apart

Ephelides (true freckles). Small, light brown, flat spots that appear and darken with sun exposure and fade in winter. Common in fair-skinned, red-haired individuals. Genetic basis. Generally appear in childhood. Almost always harmless.

Solar lentigo (sun spot, age spot, liver spot). Larger, darker, more uniform brown or tan spots that develop in middle age or later from cumulative sun exposure. Do not fade in winter. Common on the face, backs of hands, shoulders, and chest. Almost always harmless, but indicate significant lifetime UV exposure (and therefore higher melanoma risk for the person overall).

Lentigo maligna. An early form of melanoma in situ, common on chronically sun-damaged skin in older adults (face, scalp, neck, hands). Looks like a slowly growing, irregularly shaped tan-brown patch. Often mistaken for an unusually large freckle or sun spot for years before diagnosis.

The critical fact: lentigo maligna can sit at the in-situ stage for 10-15 years before progressing to lentigo maligna melanoma (invasive). Caught at the in-situ stage, it is essentially 100% curable by excision. Caught after invasion, it is a real melanoma with all the implications.

Typical freckle: 1-3mm. Rarely larger than 5mm.

Solar lentigo: 3-10mm. Sometimes larger.

Lentigo maligna: usually >6mm by the time it is noticed, often 10-20mm or larger. The D in ABCDE (Diameter over 6mm) is a flag, especially when combined with other features.

Size alone does not diagnose — large benign solar lentigines exist — but a 'freckle' over 6mm in an adult deserves closer attention than a 2mm one.

Freckle and solar lentigo: round or oval with a smooth, well-defined edge. The pigment is uniform up to a clear boundary.

Lentigo maligna: irregular, jagged, or scalloped border. The pigment fades in and out at the edges. The shape is asymmetric — one half does not mirror the other.

The B in ABCDE (Border irregularity) and A (Asymmetry) apply directly here.

Freckle and solar lentigo: uniform light to medium brown. Single shade across the lesion. May darken slightly in summer (freckles) or stay constant (lentigines).

Lentigo maligna: multiple shades within a single lesion — light brown, dark brown, black, sometimes grey or blue. The C in ABCDE (Colour variation) is one of the strongest signals for lentigo maligna. A 'freckle' that has two or more clearly different shades within it deserves a dermatologist visit.

Freckle: stable in size and shape over months to years. May darken and fade with seasons. Does not grow.

Solar lentigo: stable. May darken slightly with continued sun exposure. Does not grow significantly.

Lentigo maligna: slowly enlarges over years. Often the patient or family member notices it has 'gotten bigger' or 'spread'. The growth is gradual — not weeks, but years — which is one reason it is missed.

The E in ABCDE (Evolution) is critical. Compare a 'freckle' to your old photographs. If it has visibly enlarged or changed shape over years, evaluate it.

Freckles: any sun-exposed area, but typical pattern is many small marks on cheeks, nose, shoulders, and arms in fair-skinned people.

Solar lentigines: sun-exposed areas, especially face, backs of hands, shoulders, chest, and upper back. More common after age 40.

Lentigo maligna: most common on chronically sun-damaged skin of older adults — face (particularly cheeks, nose, forehead), scalp (in bald or thin-haired men), neck, and backs of hands. Less common on the trunk (where superficial spreading melanoma is more typical).

Freckles: childhood onset, fair skin, family pattern. New freckles in adults are uncommon.

Solar lentigines: middle age onset, history of sun exposure. Very common.

Lentigo maligna: typical patient is over 60, with chronic sun damage. Median age at diagnosis is 65-70. New 'freckle' or 'sun spot' that appears in this age group on chronically sun-damaged skin and grows over time is suspicious until proven otherwise.

A new pigmented spot in someone over 60 is the scenario in which lentigo maligna is most often missed. Do not assume it is just another sun spot without examination.

See a dermatologist for any 'freckle' that is: larger than 6mm; has irregular borders; has multiple shades of brown, black, or grey; is new in someone over 40; is changing in size or shape; is on sun-damaged skin in someone over 60.

Lentigo maligna is diagnosed by punch biopsy or excisional biopsy. Treatment is wide local excision, which is curative at the in-situ stage. The cosmetic result is good when the lesion is small. The reason to act early is not that the cancer is dangerous in the short term — it is that early diagnosis means smaller surgery and minimal scarring, while delay leads to invasive melanoma with all its risks.