Moles

What are moles?

Melanocytic naevi, commonly called moles, are benign growths made up of clusters of melanocytes, the cells that produce melanin. They can occur on different parts of the body and vary considerably in appearance. On this page, “naevus” refers to a melanocytic naevus; dermatologists also use the word for certain other skin formations.

A mole is not melanoma. An individual common mole rarely becomes melanoma, and many melanomas develop on skin where no mole was previously visible. Looking after your skin therefore involves more than monitoring or removing familiar moles. Noticing a new lesion or one that differs from the others is also important.

Congenital and acquired moles: when they appear

Congenital moles are present at birth or become apparent early in life. Acquired moles appear later, often during childhood and young adulthood. This distinction describes when a mole appeared; by itself, it does not mean that a lesion is dangerous.

Individual predisposition and sun exposure contribute to the number and appearance of moles. Some can change over a lifetime, including during pregnancy, while others fade with age. Changes should not automatically be attributed to hormones. An unusual or rapid change, or one affecting a mole unlike the others, should be discussed with a doctor.

Very extensive congenital moles need a specific assessment pathway. Location, size, features and personal history matter more than applying one rule to everyone.

Junctional, compound and intradermal naevi

These names describe where naevus cells lie within the skin. They may appear in a pathology report and are not a scale of severity.

• Junctional naevus: cells form groups at the boundary between the epidermis and dermis.
• Compound naevus: there is both a junctional component and a component within the dermis.
• Intradermal naevus: naevus cells are located in the dermis.

Appearance may suggest a category, but cannot establish the microscopic structure without appropriate assessment. A raised mole is not automatically more dangerous than a flat one, and “compound” does not mean malignant. Assessment considers the whole lesion and its behaviour over time.

Colour, shape, surface and size

Moles may be brown, darker, pink or close to the surrounding skin colour; some variants appear bluish. They can be flat or raised, smooth or uneven, and may contain hairs. A red or pigmented spot is not necessarily a mole, because different skin conditions can look alike.

Many common moles are small, but benign moles larger than 6 mm also exist. Conversely, melanoma can be smaller. Diameter alone does not distinguish a benign lesion from cancer. Hair, an even colour or an apparently regular outline are also insufficient reassurance when a lesion is changing.

Knowing your skin’s usual appearance helps you notice a spot that stands out from your other moles. Comparing it with photographs found online cannot establish a diagnosis.

Atypical moles and melanoma risk

A mole may be described as “atypical” because its clinical features differ from those of common moles. “Dysplastic” is also used in pathology and should be interpreted in the context of the report. Neither term automatically means a diagnosis of melanoma.

Having many moles or atypical moles may indicate greater overall risk and make personalised surveillance useful. Personal or family history of melanoma changes the assessment. Increased risk does not mean that every mole will become cancer, or that removing them all eliminates risk. Melanoma can develop elsewhere on the skin.

Changes to have checked: the ABCDE rule

The ABCDE rule helps describe changes to report. It is not a pass-or-fail test, and all the signs do not have to be present together.

• A — Asymmetry: one part differs from the other.
• B — Border: the outline is irregular, blurred or changing.
• C — Colour: there are changes, several shades or pigmentation unlike the usual appearance.
• D — Diameter: size deserves attention, but lesions smaller than 6 mm may also need assessment.
• E — Evolving: the mole changes in shape, size, colour, surface or symptoms.

A new spot unlike the others, noticeable growth, spontaneous bleeding, pain or persistent itching are other reasons to contact a doctor. They do not establish that a lesion is cancer, but should not be ignored. If you notice a significant change, do not wait for an already scheduled routine appointment.

Skin examination, dermoscopy and monitoring

A dermatologist considers the lesion’s history, risk factors and examination of the skin. Dermoscopy reveals structures not visible to the naked eye. For selected patients, body photographs and digital dermoscopic images help compare findings over time.

Follow-up frequency depends on individual risk; there is no single interval suitable for everyone. Mole mapping does not replace examination or mean that every lesion can simply be watched. When suspicion calls for histology, monitoring should not become a reason to delay it.

Bring previous reports or photographs and say when you first noticed the change. A concrete description such as “it has grown”, “it bled” or “it was not there before” can help the doctor.

When a mole is removed and why the report matters

Most benign moles need no treatment. Removal may be offered to assess a suspicious lesion, address repeated irritation or meet a cosmetic request after medical assessment. The reason for removal and the method should be discussed together.

If melanoma is suspected, obtaining adequate tissue for histology matters. Complete excisional biopsy is generally preferred where feasible; the approach also depends on location and size. A pathologist examines the tissue to establish its nature and inform any further steps.

Avoid home removal attempts and corrosive products, which can cause injury and delay diagnosis. A pigmented lesion should be assessed before a purely destructive treatment is considered. After removal, keep the pathology report and follow the advice given, even if the wound has already healed.

Protecting and observing your skin

UV protection and attention to changes serve complementary purposes. Seek shade, wear protective clothing and use broad-spectrum sunscreen according to its instructions. Avoid tanning lamps and sunbeds. Sunscreen does not make prolonged exposure safe.

Self-examination covers all your skin, not just the most noticeable moles. Use a mirror or ask for help with the back, scalp and other hard-to-see areas. Photographs can document change but should not delay assessment. The aim is to notice and report changes, rather than classify every mole yourself.