The red flags for skin cancer you should never ignore

Summer is well and truly upon us, with record-breaking temperatures seeing London reaching 35°C in May – beating temperatures in Havana, Barcelona, Cape Town, and Mexico City. Extreme heat is expected to become more common in the coming years, so it’s time to start thinking about sun safety.

Five or more sunburns in your lifetime – wherever you are in the world – can double your risk of melanoma skin cancer. And analysis from Cancer Research UK shows that melanoma rates have increased by around a quarter in the last decade, rising faster than any other common cancer. For non-melanoma skin cancer, which is typically less deadly but still serious, rates have more than doubled since the 1990s.

This rise may sound alarming, but it’s important to note that 90 per cent of skin cancer cases each year are preventable, and are caused by exposure to too much ultraviolet (UV) radiation from the sun and sunbeds.

Non-melanoma skin cancer (NMSC) is currently the most common type of cancer globally and while NMSCs have a high survival rate in comparison to melanoma, awareness of them is lower. Basal cell carcinoma (BCC) is the most common skin cancer in the UK, accounting for 75 per cent of all skin cancers. Melanoma lesions are usually the ones people fear the most, as they can be deadly and may be mistaken for benign moles.

Cure rates for non-melanoma skin cancers caught early are exceptional, often exceeding 95 per cent, so early detection is key. Here, specialist GP and dermatologist Dr Yvonne Abimbola and founder of Dr Eve Skin, explains the skin cancer red flags to look out for.

Know your ABCs

Melanoma often begins as a new mole or a change in an existing mole. Abimbola says: “One of the most important things we try to get across to patients in clinic is that checking for skin cancer is as easy as ABC.”

Abimbola explains the “ABCDE rule”:

• A – Asymmetry: one half of the mole looks different from the other half. Benign moles are usually symmetrical.
• B – Border: melanomas often have irregular, scalloped, or poorly defined borders. Non-cancerous moles typically have smooth, well-defined edges.
• C – Colour: look for moles that have uneven colouring, with shades of brown, black, red, white, or blue. Healthy moles are usually one uniform colour.
• D – Diameter: melanomas are typically larger than the size of a pencil eraser (about 6 mm). However, they can still be smaller, especially in the early stages.
• E – Evolution: any change in the mole’s appearance over time, such as size, shape, colour, or texture, can indicate melanoma. This includes itching, bleeding, or crusting.

If you notice any spots that match these warning signs, it is important to schedule an appointment with a GP or dermatologist for a professional evaluation.

Watch out for an ugly duckling mole

The “ugly duckling” mole is one that simply looks different from all your other moles – it may be darker, larger, or just stand out. Abimbola says that if you notice this, it is worthy of a review by your GP.

Abimbola says the “ugly duckling” sign is a highly effective way for both patients and doctors to spot early-stage melanoma. “Melanomas often do not look like normal, healthy moles, causing them to stick out like a sore thumb. An ugly duckling mole might differ in colour, size and suddenly appear, grow rapidly, or change while nearby moles stay the same.”

Unexplained skin changes

If you have a sore that might bleed or keep scabbing over and doesn’t heal, Abimbola says this could be a sign of non-melanoma skin cancer.

You should also be vigilant about patches on your skin that look different to their surrounding area. These patches could be flat or raised. They could also be crusty, scaly, itchy, painful or bleed. They might be red in colour. In darker skin tones, the patch might be darker than the surrounding skin rather than red.

Speak to your GP as soon as possible if you notice an unexplained skin change which:

• grows or bleeds
• forms a scab which falls off and grows again
• is itchy, crusty, scaly, or painful
• does not heal

Black or brown streaks in your nail

Abimbola says a change in nail pigmentation, especially a dark streak that widens and/or involves the surrounding skin without any prior trauma, should raise an alarm. This may be a rare type of skin cancer – subungual melanoma.

Subungual melanoma can be difficult to detect early on because the symptoms may be hidden or subtle. Warning signs to take seriously include:

• A bruise on your nail that doesn’t diminish or move as your nail grows
• A nail that separates from your nail bed
• Black or brown streaks in your nail, unrelated to an injury
• Cracking or thinning of your nail plate
• Darkening skin next to your nail
• Nail streaks that increase in size

How often should you check for moles?

Abimbola recommends that people regularly check their skin for moles and track any changes. “Don’t forget places that are easily missed, like your ears, scalp, soles of your feet, palms, and the back of your body.”

She advises checking yourself on the first of every month, and taking pictures and tracking any changes, “Note if you have new moles, or if any existing moles have changed. Keep a folder in your phone for pictures, so you can show these to your GP or dermatologist.”

If you think you have moles in hard to see places, enlist a friend to help out and for scalp lesions, speak to your hairdresser to check for changes and if you get regular facial or body treatments, ask your dermatologist to check any areas of concern you may have.

“If in doubt, get it checked out! Most changes turn out to be harmless, but it’s always better to be reassured early than to miss something important,” says Abimbola.