When Should You Worry About a Mole?

Five Findings That Mean Book Now

Any one of these is sufficient on its own. They do not need to occur together, and none of them means cancer — they mean assessment.

1. It bleeds, or it will not heal. A lesion that bleeds on light contact, or a spot that has not healed in a month, is the single most useful non-mole warning sign there is. Skin heals; skin cancers do not.
2. It is changing. Size, shape, colour, surface or sensation, over weeks to months. Change is a stronger signal than appearance at one moment.
3. It is new and you are over 40. Most ordinary moles appear in the first two decades of life. A genuinely new pigmented lesion in middle age deserves a look.
4. It does not match your others. The ugly duckling sign: your moles tend to share a family resemblance, and the one that stands out from the crowd is the one to raise.
5. It itches, stings or is tender persistently. Not a single itchy afternoon — a symptom that keeps coming back to the same spot.

ABCDE, and Which Letters Carry Weight

The checklist is useful, but the letters are not equal and it helps to know which ones to lean on.

Most people use this list upside down, treating size as decisive and change as background noise. It is the other way round. The detail behind that ranking, including the presentations that break the rules altogether, is in early melanoma detection.

What an Ordinary Mole Looks Like

Worth knowing, because most of what people worry about is this.

A typical benign naevus is round or oval, evenly coloured in one shade of brown or tan, with a clean edge, usually under 6 mm, and it looks broadly like your other moles. It may be flat or raised; raised is not a bad sign in itself and is often just an older, more mature mole. It stays much the same year after year, and it may fade or slowly disappear over decades.

Moles can appear anywhere, they run in families, and having a lot of them is a risk factor for melanoma without any individual one being a problem. Hormonal periods — pregnancy, adolescence — can darken existing moles fairly uniformly, which is different from one mole changing on its own.

Skin Cancer Does Not Have One Appearance

People search for what skin cancer looks like and are shown melanoma photographs, which is a partial answer. Three common skin cancers, three quite different appearances:

Basal cell carcinoma — the most common

A pearly or waxy bump, sometimes with fine visible blood vessels across it, or a flat scaly patch. It often bleeds, scabs, appears to heal and then breaks down again in the same place. It grows very slowly and rarely spreads, but it does not stop.

Squamous cell carcinoma

A firm, scaly or crusted lump, often tender, sometimes with a central crust that keeps reforming. Typically on sun-exposed skin — scalp, ear, lip, back of the hand.

Melanoma

Usually pigmented and irregular, but not always: nodular melanoma can be symmetrical, evenly coloured and firm, and amelanotic melanoma has little pigment at all and can look pink or skin-coloured.

The unifying thread is not colour or shape. It is a lesion that behaves differently from the skin around it — persisting, growing, bleeding or refusing to heal.

The Signs People Under-Read

“Patients are very good at spotting the mole that is dark, raised and obvious — usually the one that has been there for twenty years. They consistently miss the ones on the back and the back of the legs, and the pale and pink ones that do not look like moles at all.”— Mr Onur Gilleard, Consultant Plastic Surgeon

• Pale, pink or skin-coloured lesions — they do not read as moles, so they are not checked
• Anything on the back, the backs of the legs, the scalp or the soles — not because these sites are riskier but because nobody is looking at them
• A firm nodule that is growing, even if it is symmetrical and evenly coloured — firmness and growth outrank a tidy appearance
• A dark streak in a nail that appears without injury

The Signs People Over-Read

• A mole you have suddenly noticed. Noticing is not the same as new. If you can find it in an old photograph, it has been there.
• A dark, raised, long-standing mole that has looked exactly the same for fifteen years. Stability is reassuring; it is change that matters.
• One itchy day. Persistent, recurring symptoms count. A single itch after a hot day does not.
• A mole that was caught by a razor and bled. Trauma explains bleeding. Bleeding without trauma does not have an explanation, and that is the version that matters.
• Moles darkening during pregnancy, fairly evenly across many of them. One mole changing on its own is the finding to raise.

None of these means ignore it. They mean the timescale is a routine appointment rather than an urgent one.

What Happens If You Come In

Examination with dermoscopy, which shows the structures beneath the surface that decide the question — and which is the reason a clinical opinion is worth more than a photograph or an app. If removal is the answer it happens at the same appointment, under local anaesthetic. A consultation is £100; removal is £350 and histological analysis £180 where the lesion’s features warrant it.

If a lesion looks urgently suspicious, the NHS two-week suspected-cancer pathway through a GP is fast and free and is the right route — paying privately does not move a genuinely urgent case forward. The criteria are in removal on the NHS. Otherwise: mole removal or contact the clinic.

Common Questions

When should I worry about a mole?

When it bleeds or will not heal, when it is changing, when it is new and you are over 40, when it looks unlike your other moles, or when it itches or hurts persistently. Any one of those is a reason to have it examined, and none of them means cancer.

Is a bleeding mole always cancer?

No. The most common reason a mole bleeds is that it was caught — by a razor, a strap or a fingernail — and trauma explains it. Bleeding with no explanation, or bleeding that keeps recurring from the same spot, is different and should be examined promptly.

How can I tell a mole from skin cancer?

Not reliably by looking, which is the honest answer. A normal mole is evenly coloured with a clean edge and stays the same; skin cancers persist, grow, bleed or fail to heal. The three common types look quite different from one another, which is why a single mental image of “what skin cancer looks like” is misleading.

Is a raised mole more dangerous than a flat one?

Not in itself. Many ordinary moles become raised as they mature. What matters is a lesion that is becoming raised or firm when it was not before, particularly if it is also growing.

My mole is bigger than 6 mm. Is that a problem?

On its own, usually not. Diameter is the weakest item on the ABCDE list — plenty of harmless moles exceed 6 mm and melanomas are frequently found smaller. Change matters far more than size.

My mole itches. Should I be concerned?

A single episode, no. Persistent or recurring itching, stinging or tenderness in one specific lesion is worth having examined, particularly alongside any change in appearance.

I have a new mole in my forties. Is that normal?

Most moles appear in the first two decades, so a genuinely new pigmented lesion in middle age is worth showing to someone. It is often harmless — a seborrhoeic keratosis or a lentigo rather than a mole at all — but that distinction is made by examination.

Can an app tell me whether my mole is dangerous?

No. A phone photograph does not capture the subsurface structures a diagnosis rests on, and a reassuring score carries no information. Use one as a prompt to attend if you like, never as a reason not to — see mole-check apps versus clinical examination.