Skin cancer: symptoms, treatment and survival

Skin cancer is a malignant tumour that develops in the cells of the skin. There are three main types: basal cell carcinoma (BCC, the most common, rarely spreads), squamous cell carcinoma (SCC, more likely to spread than BCC) and melanoma (the most dangerous, arising from pigment cells and responsible for most skin cancer deaths). Together, these cancers make skin cancer the most commonly diagnosed cancer group in the UK, with over 350,000 cases per year.

The three main types are: BCC (basal cell carcinoma) — the most common, arising from basal cells, rarely spreads, almost always curable; SCC (squamous cell carcinoma) — arising from squamous cells, can spread if untreated, generally curable when caught early; and melanoma — the most dangerous, arising from melanocytes, capable of rapid spread, causing approximately 80% of skin cancer deaths. Less common types include Merkel cell carcinoma, cutaneous lymphoma and Kaposi sarcoma.

Skin cancer is the most common cancer in the UK. Over 350,000 cases are diagnosed each year — approximately 300,000 BCCs, approximately 45,000 SCCs and approximately 16,000 melanomas. Non-melanoma skin cancer (BCC plus SCC) accounts for the vast majority of cases and is almost always curable. Skin cancer incidence has been rising steadily for decades due to increased UV exposure and sunbed use.

Symptoms vary by type. BCC: a pearly, shiny bump or a sore that repeatedly heals and reopens. SCC: a firm, red or skin-coloured lump that grows quickly, may be tender, and may ulcerate. Melanoma: a new or changing mole with asymmetry, irregular borders, multiple colours, diameter over 6 mm or evolution. General warning signs include: any skin lesion that does not heal within six weeks, bleeds without obvious cause, or has changed in size, shape or colour.

UV radiation from the sun and sunbeds is the primary cause of all three main types of skin cancer. UV damages DNA in skin cells, triggering mutations that allow uncontrolled growth. Cumulative UV exposure drives BCC and SCC; intermittent intense exposure and sunburn — particularly in childhood — is more closely associated with melanoma. Other risk factors include immunosuppression, fair skin and previous skin cancer.

Yes. Sun exposure is the leading cause of skin cancer in the UK and worldwide. Both UVB radiation (which causes sunburn) and UVA radiation (which penetrates deeper and causes DNA damage without visible burning) contribute to skin cancer risk. The NHS advises: using SPF 30+ broad-spectrum sunscreen; wearing protective clothing; seeking shade during 11am–3pm; and avoiding sunbeds. Sunscreen should be applied generously and reapplied every two hours.

Non-melanoma skin cancer (NMSC) refers primarily to BCC and SCC — tumours arising from epidermal cells that very rarely (BCC) or occasionally (SCC) spread to other parts of the body. Melanoma arises from melanocytes and has a much greater propensity to metastasise rapidly to lymph nodes and distant organs. Melanoma is far more dangerous: it accounts for approximately 4% of skin cancer cases but approximately 80% of skin cancer deaths.

A suspicious skin lesion is assessed clinically by a GP or dermatologist, aided by dermoscopy. If skin cancer is suspected, the NHS Two Week Wait pathway ensures urgent referral to a dermatologist. Diagnosis is confirmed by biopsy — a small piece of tissue is removed under local anaesthetic and examined by a pathologist. For melanoma, the entire lesion is excised (not just biopsied). Staging investigations (CT, PET-CT, sentinel lymph node biopsy) are performed for invasive SCC and melanoma.

BCC: a pearly, pink or skin-coloured shiny bump; a flat scar-like area; a pink growth with raised rolled edges; or a sore that bleeds and heals repeatedly. SCC: a firm red, scaly or crusted lump that may be tender and grows over weeks to months, sometimes ulcerating. Melanoma: a new or changing mole that is asymmetrical, has irregular borders, contains multiple colours, is larger than 6 mm or is evolving. Any suspicious or non-healing skin lesion should be assessed by a GP.

The ABCDE rule is an NHS-recommended tool for assessing moles and pigmented skin lesions: A — Asymmetry; B — Border (irregular, ragged or blurred edges); C — Colour (more than one colour or shade within the lesion); D — Diameter (greater than 6 mm, though smaller melanomas exist); E — Evolution (any change in size, shape, colour or sensation, or any new symptom such as bleeding, crusting or itching). Any lesion meeting one or more criteria should be assessed promptly by a GP.

Treatment depends on the type and stage. BCC: surgical excision, Mohs surgery, cryotherapy, curettage, topical imiquimod or 5-FU, PDT, radiotherapy; vismodegib for advanced disease. SCC: surgical excision or Mohs surgery; radiotherapy for inoperable disease; cemiplimab (immunotherapy) for advanced/metastatic SCC. Melanoma: wide local excision for localised disease; immunotherapy (pembrolizumab, nivolumab ± ipilimumab) or BRAF/MEK inhibitors for advanced/metastatic disease.

Mohs micrographic surgery is a specialised technique used for high-risk and facial skin cancers. The surgeon removes the cancer one layer at a time, immediately examining each layer under a microscope to check whether it is cancer-free. Removal continues only in areas where cancer cells remain, until completely clear margins are confirmed. Mohs surgery achieves the highest cure rates (over 98% for primary BCC) while maximally preserving normal tissue — particularly important on the face, around the eyes, nose and ears.

Survival rates vary by type. BCC: cure rate exceeds 95% with appropriate treatment; BCC-specific deaths are extremely rare. SCC: five-year survival for localised disease is approximately 90–95%; for metastatic SCC it falls to 25–35% (improving with immunotherapy). Melanoma: five-year survival exceeds 95% for Stage I; approximately 80% for Stage II; 60% for Stage III; 25% for Stage IV (rising to 40%+ with combination immunotherapy in some patient groups).

Risk is highest in people with: fair or freckled skin, blue or green eyes, red or blonde hair; a history of sunburn or prolonged sun exposure; regular sunbed use; a personal or family history of skin cancer; many moles or atypical moles; immunosuppression; outdoor occupations; previous exposure to ionising radiation or arsenic; and certain genetic conditions (Gorlin syndrome, xeroderma pigmentosum). People from all backgrounds can develop skin cancer.

Yes. While BCC and SCC most commonly occur on sun-exposed areas (face, scalp, ears, neck, hands), they can develop anywhere. Melanoma most commonly appears on the back in men and the legs in women, but can arise on any skin surface including the palms, soles, under nails and mucous membranes. Uveal melanoma develops in the eye. Any new or changing skin lesion on any part of the body should be assessed by a GP.

Most skin cancer is preventable. The NHS advises: applying SPF 30 or higher broad-spectrum sunscreen to all exposed skin; reapplying every two hours and after swimming; wearing a wide-brimmed hat, UV-protective clothing and sunglasses; seeking shade between 11am and 3pm; avoiding sunbeds entirely; and performing regular skin self-examination to detect changes early. Children's skin should be particularly well protected as sunburn in childhood significantly increases lifetime cancer risk.

The NHS recommends using a sunscreen with at least SPF 30 for everyday use, and SPF 50 for children, people with fair or very fair skin, and for periods of prolonged or intense sun exposure. Choose a broad-spectrum product (protecting against both UVA and UVB). Apply generously — most people use less than half the amount needed for the stated protection. Reapply every two hours and immediately after swimming or towel-drying. Sunscreen should be used alongside shade and protective clothing, not as the sole form of protection.

Yes. The WHO classifies sunbeds as Group 1 carcinogens — the highest cancer risk category, reserved for agents with conclusive evidence of human carcinogenicity. Sunbed use before age 35 increases the lifetime risk of melanoma by approximately 75%. Sunbeds expose users to concentrated UVA and sometimes UVB radiation, causing DNA damage in skin cells. The UK banned commercial sunbed use by under-18s in 2011. The NHS advises avoiding sunbeds entirely, regardless of age.

Darker skin (higher melanin content) does provide some natural protection against UV radiation compared with very fair skin, and BCC and SCC are significantly less common in people with dark skin. However, melanoma can and does develop in people of all skin types. Acral lentiginous melanoma — occurring on the palms, soles and under nails — is the most common melanoma subtype in people with darker skin and is often diagnosed at a later stage due to lower awareness among both patients and clinicians.

In low-income countries, dermatology services are highly concentrated in urban hospitals, meaning patients in rural areas commonly present with large, advanced skin cancers. Mohs surgery, PDT, immunotherapy and targeted therapy are largely unavailable. Even simple excision may require long travel and out-of-pocket costs beyond many patients' means. World Aid Network funds cancer treatment — including skin cancer — for poor patients through locally-licensed doctors, working to close this inequality.