A spot that catches on your towel, a mole that looks different from the rest, or a sore that keeps crusting over is worth your attention. Suspicious skin lesions are not always cancer, but in Australia’s high-UV environment, waiting to see whether a change settles can cost valuable time. Knowledge can save your life – and a prompt skin check can provide either reassurance or an early path to treatment.
What makes a skin lesion suspicious?
A skin lesion is any area of skin that looks or feels different from the surrounding skin. It may be a mole, freckle, lump, scaly patch, ulcer, pigmented mark or sore. Many lesions are benign, including common moles, age spots, skin tags and seborrhoeic keratoses. The challenge is that skin cancers can initially look subtle and may resemble harmless marks.
The most useful question is not, “Does this look like a textbook melanoma?” It is, “Is this new, changing, unusual for me, or failing to heal?” A lesion deserves clinical assessment when it changes in size, shape, colour, texture or sensation. It should also be checked if it bleeds, crusts, itches persistently, becomes tender or returns after seeming to heal.
Trust what you notice. You know your skin better than anyone else. A new mark in adulthood is not automatically dangerous, but it should not be dismissed simply because it is small or painless.
Warning signs of suspicious skin lesions
The ABCDE signs for melanoma
Melanoma can develop in an existing mole or appear as a new spot. It may be brown, black, pink, red, blue, grey or even close to skin-coloured. The ABCDE guide can help you identify features that need attention:
- A – Asymmetry: one half does not match the other.
- B – Border: edges are blurred, irregular, scalloped or poorly defined.
- C – Colour: more than one colour is present, or the colour is changing.
- D – Diameter: the spot is larger than 6 mm, although melanomas can be smaller.
- E – Evolving: it is changing, growing, bleeding, itching or behaving differently.
ABCDE is a useful prompt, not a rule-out test. Some melanomas are symmetrical, small and evenly coloured. The “ugly duckling” sign is equally valuable: look for a spot that stands apart from your usual pattern of moles. If most of your moles look alike and one is noticeably darker, larger or different in shape, arrange a skin check.
Sores and scaly areas that do not heal
Basal cell carcinoma and squamous cell carcinoma often do not resemble a dark mole. A basal cell carcinoma may look like a pearly or shiny bump, a pink patch, a small open sore, or a scar-like area that slowly enlarges. It can bleed after minor contact and may form a recurring crust.
Squamous cell carcinoma can appear as a thickened, rough, tender or scaly patch, a rapidly growing lump, or a sore that does not heal. These cancers are common on sun-exposed areas such as the face, ears, scalp, neck, forearms and backs of the hands. They need timely assessment because, while many are highly treatable, some can grow deeper or spread if left untreated.
A rough patch on the face, ears or bald scalp may also be an actinic keratosis, caused by cumulative sun damage. It is not the same as invasive skin cancer, but it should be assessed, particularly if it is persistent, sore, thickening or multiplying.
Changes that should not wait
Book an appointment promptly if you have a lesion that is bleeding without a clear injury, growing quickly, painful, ulcerated, or not healing within a few weeks. The same applies to a dark streak or changing pigment under a fingernail or toenail, especially if it is widening or pigment extends onto the surrounding skin.
Skin cancer can occur in places that receive little sun. Check the soles of your feet, between toes, palms, buttocks, genitals and scalp. Ask a partner, family member or hairdresser to alert you to changing spots in areas you cannot easily see.
People with skin of colour can develop skin cancer too, and it may be diagnosed later when changes are overlooked or assumed to be low risk. Pay particular attention to the palms, soles, nails, lips and areas of chronic scarring or inflammation. Any changing or non-healing lesion deserves the same careful assessment, regardless of skin tone.
A changing spot is usually not an emergency department issue unless there is severe bleeding, infection or another urgent concern. However, it is not a reason to wait months for a routine appointment. Contact a GP or qualified skin check clinic and explain that you have a changing or non-healing lesion when booking.
Who should be especially vigilant?
Everyone should know their own skin, but risk is higher for people with fair skin, a history of sunburn, many moles, freckles, or a personal or family history of melanoma. Outdoor workers, regular beachgoers, gardeners, athletes and people who spend long periods driving or working outdoors accumulate UV exposure over time.
Age matters, but it is not a safeguard. Skin cancer becomes more common with age, yet melanoma affects younger adults as well. A past skin cancer also increases the chance of developing another. If you have previously had melanoma, basal cell carcinoma, squamous cell carcinoma or numerous actinic keratoses, follow the review schedule advised by your treating clinician.
Smoking increases the risk of lip cancer, particularly when combined with chronic sun exposure. Persistent scaling, thickening, cracking or a non-healing sore on the lip should be checked by a doctor or dentist without delay.
What happens at a skin check?
A clinician will ask when you first noticed the lesion, whether it has changed, and about your personal and family history. They will examine the spot closely, often using a dermatoscope – a handheld device that magnifies structures below the skin surface. A full-body skin examination may be recommended depending on your risk and the reason for your visit.
If a lesion is concerning, the clinician may photograph and monitor it, arrange a biopsy, or remove it. A biopsy is the only way to confirm whether a lesion is cancerous. This can sound worrying, but early assessment is the practical step that turns uncertainty into a clear plan.
Not every suspicious-looking mark requires removal. Some can be monitored safely when the clinical features and your history support that approach. On the other hand, a lesion that looks minor to the naked eye may need biopsy. This is why online images, pharmacy apps and self-diagnosis cannot replace an in-person examination.
Check your skin regularly, but do not rely on self-checks alone
A monthly self-check is a sensible habit, especially if you have increased risk. Use a mirror in good light and work methodically from your scalp and face to the soles of your feet. Take photographs of spots you are watching, with the date recorded, so changes are easier to identify.
Self-checks are most effective when paired with sun protection and professional review when something changes. Wear protective clothing, a broad-brimmed hat and sunglasses, seek shade, and apply SPF 50+ broad-spectrum sunscreen generously and regularly. These measures reduce UV damage, but they do not erase past exposure or remove the need to check new and changing marks.
If a spot is worrying you, do not wait for it to become dramatic. Make the appointment, take note of when you first saw the change, and let a qualified clinician examine it. Every minute counts when a skin cancer is developing, and early action gives you the best chance of a simple, effective outcome.