Skin Cancer

Skin Cancer Explained

Skin cancer occurs when the cells in the outermost layer of your skin (the epidermis) begin to grow in an uncontrolled way. The main risk factor for developing this disease is ultraviolet (UV) radiation from the sun. Consequently, most cancers appear on skin that receives a lot of sunlight, although they can also form on areas that are usually covered. In Australia, skin cancer is the most prevalent cancer type, making up roughly 80% of all newly diagnosed cases. Australia also has some of the highest incidence rates globally, two to three times greater than those seen in Canada, the United States, and the United Kingdom. The good news is that the vast majority of skin cancers are preventable.

Spot checks

Performing regular self-examinations is crucial for early detection and protection against skin cancer. During these checks, your pharmacist will photograph one to three spots of concern and send the images to a skin cancer specialist for review. You’ll receive a detailed report via email within 48 hours.

Types of skin cancer

Skin cancers are categorized by the type of cell in which they originate:

• Basal cell carcinoma (BCC): The most common but least aggressive form. It develops slowly in the basal layer of the epidermis. BCCs rarely spread (metastasize) to distant organs but can invade nearby tissues.
• Squamous cell carcinoma (SCC): Originating in the flat keratinocyte cells of the epidermis, SCC can grow more rapidly than BCC and has the potential to spread if not treated.
• Melanoma: Arising from melanocytes, the pigment-producing cells, melanoma is the most serious form. Although it is less common, it can develop quickly from new or existing moles over weeks or months. Australia records over 13,000 new melanoma diagnoses each year.

What does skin cancer look like?

Early signs typically involve noticeable changes in your skin’s appearance, for example:

• A spot that no longer looks the way it did before.
• An area of skin that becomes red, scaly, or thickened.
• A new or unusual mole, freckle, or sore.
• A lesion that changes in colour, shape, or size, or that itches or bleeds.
• A spot with uneven or notched borders.

Appearance varies by type:

• BCC often appears as a pearly, pale, or reddish bump, or as a flat patch of pink skin.
• SCC may look like a thickened, red, scaly area that crusts, bleeds, or ulcerates easily.
• Melanoma can present as a brand-new spot or an existing mole that shifts in hue, size, or outline.

What triggers skin cancer?

Nearly all skin cancers arise from ultraviolet (UV) rays emitted by the sun. These rays penetrate the epidermis and cause DNA damage, and with each dose of exposure, the harm accumulates. Over time, this damage prevents normal cell repair, allowing abnormal cells to proliferate unchecked. Although anyone can develop skin cancer, the likelihood grows as you age. Additional risk factors for skin cancer include:

• A personal history of skin cancer or a family history of the disease
• Fair or freckled skin that burns easily
• Red or light-coloured hair and light-coloured eyes
• Numerous moles, freckles, or solar lentigines (sunspots)
• A weakened immune system due to illness or medication
• Regular use of indoor tanning beds or sunlamps

How is skin cancer detected?

A general practitioner or a dermatologist usually identifies skin cancer by performing a thorough examination of the skin’s surface. If any lesion appears suspicious, they may carry out a biopsy, removing a small tissue sample to examine under a microscope for cancerous cells.

What treatments are available?

The standard approach to treating skin cancer is surgical excision. In early-stage cases, the surgeon removes the lesion under local anaesthetic, excising a margin of healthy tissue to ensure complete removal. For more advanced tumours, additional surrounding tissue may need to be taken out to leave no malignant remnants. Other possible treatments include:

• Topical medications applied directly to the lesion
• Radiotherapy, which uses high-energy rays to destroy cancer cells
• Cryotherapy, freezing the tumour with liquid nitrogen
• Curettage, scraping away the growth with a curette
• Cautery, burning off the abnormal tissue

What happens if skin cancer is left untreated?

Early detection vastly improves the effectiveness of therapy; about 95% of cases are curable when caught promptly. If neglected, skin cancer can invade nearby tissues or spread (metastasize) to distant organs. In aggressive forms like melanoma, this can necessitate extensive surgery leading to disfigurement, and in some cases, can be life-threatening.

How to examine your skin for cancer

Recognising the normal look and feel of your skin is crucial so you can spot any alterations early. While there’s no fixed schedule for self-checks, making them a routine habit is highly recommended. The Cancer Council suggests you:

• Use a well-lit room.
• Remove all clothing for a comprehensive view.
• Stand before a full-length mirror to survey your entire body.
• Employ a handheld mirror, or enlist a helper, to inspect hard-to-see areas.
• Examine every inch of your skin, not just sun-exposed zones.

When screening for melanoma, apply the ABCDE rule:

• Asymmetry: Are the two halves of a mole dissimilar?
• Borders: Are the edges irregular, notched, or scalloped?
• Colour: Are multiple hues present?
• Diameter: Is it over 6 mm across, or smaller but growing?
• Evolving: Has the spot altered in any way?

Pay special attention to:

• Face and scalp
• Neck and shoulders
• Front and back of your arms, including armpits
• Palms and backs of your hands, between your fingers, and under your fingernails
• Front and back of your legs
• Tops and soles of your feet, plus the spaces between your toes

Look out for:

• Spots that feel or appear different from others
• Lesions that have changed in colour, texture, size, or shape
• Sores that fail to heal after two weeks
• Areas that itch or bleed

When to see your doctor

If you notice any new or unusual skin changes, book an appointment with your GP or a dermatologist. Discuss your personal risk, this will help them determine if you need more frequent, professional skin examinations.

Can you prevent skin cancer?

Yes, most skin cancers are largely preventable by reducing UV exposure. When the UV index is 3 or above, you should:

• Slip on clothing that covers as much skin as possible.
• Slop on a broad-spectrum, water-resistant SPF 30+ sunscreen at least 20 minutes before going out and reapply every two hours.
• Slap on a wide-brimmed hat.
• Seek shade whenever you can.
• Slide on UV-blocking sunglasses that meet safety standards.

You can check the UV index in Australian newspapers’ weather sections, on the Bureau of Meteorology website, or via the free SunSmart app. Sun protection toolkit

• Wide-brimmed hat
• Sunglasses
• Long-sleeved swimwear or rash vest
• Sunscreen SPF 50+
• Beach umbrella or shade rated SPF 50+
• Regular self-examinations
• A positive mindset
• Consistency