What is non-melanoma skin cancer?

Non-melanoma skin cancer (NMSC) is an umbrella term for skin cancers that are not melanoma — primarily basal cell carcinoma (BCC, approximately 80%) and squamous cell carcinoma (SCC, approximately 20%), along with rarer types (Merkel cell carcinoma, sebaceous carcinoma, dermatofibrosarcoma protuberans). NMSC is the most common cancer type globally, predominantly caused by ultraviolet radiation. Despite its enormous incidence, NMSC is often excluded from national cancer registries, meaning global figures are vastly underestimated. Most NMSC is highly curable when treated early.

What is the difference between BCC and SCC?

Basal cell carcinoma (BCC): the most common; arises from the base of the skin epidermis; pearly, shiny nodule with rolled borders and visible blood vessels (telangiectasia); very rarely spreads beyond the skin (<0.5% metastasis rate); can cause significant local tissue destruction if neglected; treated by surgery (Mohs, excision) or radiotherapy; most arise on the face and scalp. Squamous cell carcinoma (SCC): arises from keratinocytes of the upper skin layers; can look like a rough, thick scaly patch, ulcerated nodule or raised lesion; approximately 5% spread to lymph nodes (higher risk for lip, ear, immunosuppressed patients); can arise from precancerous actinic keratosis; treated by excision, Mohs, radiotherapy, or — for advanced SCC — cemiplimab/pembrolizumab.

Who is at highest risk?

Primary risk factors: fair skin (Fitzpatrick type I/II — burns easily, tans poorly); cumulative lifetime UV exposure (SCC risk); intense intermittent UV exposure/sunburns (BCC risk); tanning bed use (IARC Group 1 carcinogen); personal or family history of skin cancer; immunosuppression (transplant recipients: 65-100× elevated SCC risk; HIV; haematological malignancy; prolonged corticosteroids); previous skin radiation; occupational UV exposure (farmers, construction workers, outdoor labourers); arsenic exposure (industrial or high-arsenic water).

Surgical excision (with adequate margins) is the mainstay for most BCC and SCC. Mohs micrographic surgery: for high-risk or cosmetically sensitive lesions — achieves >99% cure rates. Radiotherapy: for patients unfit for surgery or with positive margins. Topical treatments (superficial BCC and AK): imiquimod; 5-fluorouracil; photodynamic therapy (PDT). Cryotherapy: for AK and small superficial BCC. Vismodegib/sonidegib (hedgehog pathway inhibitors): for locally advanced or metastatic BCC. Cemiplimab/pembrolizumab (PD-1 inhibitors): for locally advanced or metastatic cSCC.

How does sun protection prevent skin cancer?

Regular sunscreen use (SPF30+ applied correctly) reduces SCC risk by approximately 40% and BCC by approximately 25% in high-UV settings (NHMRC Green Island study, Australia). Avoiding tanning beds reduces NMSC and melanoma risk substantially. Key prevention: avoid peak UV hours (10am-4pm); seek shade; wear broad-spectrum SPF50+ sunscreen; protective clothing (long sleeves, hat, UV-wrap sunglasses); regular skin self-examination and annual professional skin checks (especially in immunosuppressed).

How does GMJ News cover NMSC?

GMJ News covers WHO NMSC burden data, BCC vs SCC distinctions, transplant immunosuppression risk, actinic keratosis as precancerous lesion, Mohs surgery, cemiplimab for advanced SCC, UV protection evidence, and tanning bed carcinogenicity. NMSC — the most common cancer globally — is directly relevant to PHIG's cancer prevention programme and Georgia's sun exposure public health messaging.

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Non-Melanoma Skin Cancer

Q: Who is at highest risk?

Primary risk factors: fair skin (Fitzpatrick type I/II — burns easily, tans poorly); cumulative lifetime UV exposure (SCC risk); intense intermittent UV exposure/sunburns (BCC risk); tanning bed use (IARC Group 1 carcinogen); personal or family history of skin cancer; immunosuppression (transplant recipients: 65-100× elevated SCC risk; HIV; haematological malignancy; prolonged corticosteroids); previous skin radiation; occupational UV exposure (farmers, construction workers, outdoor labourers); arsenic exposure (industrial or high-arsenic water).

Q: How is NMSC treated?

Surgical excision (with adequate margins) is the mainstay for most BCC and SCC. Mohs micrographic surgery: for high-risk or cosmetically sensitive lesions — achieves >99% cure rates. Radiotherapy: for patients unfit for surgery or with positive margins. Topical treatments (superficial BCC and AK): imiquimod; 5-fluorouracil; photodynamic therapy (PDT). Cryotherapy: for AK and small superficial BCC. Vismodegib/sonidegib (hedgehog pathway inhibitors): for locally advanced or metastatic BCC. Cemiplimab/pembrolizumab (PD-1 inhibitors): for locally advanced or metastatic cSCC.

GMJ News knowledge hub · last reviewed September 2026 · Georgian Medical Journal

Summary Statistics Glossary GMJ news FAQ Documents Organizations Research

Non-melanoma skin cancer (NMSC) — comprising basal cell carcinoma (BCC, approximately 80%) and squamous cell carcinoma (SCC, approximately 20%) — is the most common cancer type globally, with an estimated 5-6 million new cases per year in the US alone and millions more worldwide; despite its generally high curability, SCC causes approximately 50,000 deaths per year globally and is responsible for 75% of skin cancer mortality despite being far less publicised than melanoma (WHO). Organ transplant recipients face a 65-100 fold elevated SCC risk from immunosuppression — making NMSC a critical survivorship concern in transplant medicine — while cemiplimab (Libtayo) and pembrolizumab have transformed outcomes for the minority of cases that progress to advanced or metastatic SCC.

Key messages

Most common cancer globally — millions/year, mostly unreported

Non-melanoma skin cancer (BCC + SCC) is the most common cancer type globally — with 5-6+ million cases per year in the US alone. Most cancer registries exclude NMSC, meaning global figures are vastly underreported. SCC causes approximately 50,000 deaths/year — 75% of skin cancer mortality (WHO).

UV radiation — the dominant modifiable cause

Ultraviolet radiation (UV-A and UV-B from sunlight and tanning beds) is the primary carcinogen for both BCC and SCC. Cumulative lifetime UV exposure determines SCC risk; intermittent intense UV exposures (sunburns) particularly drive BCC risk.

BCC vs SCC — different behaviours

BCC: slow-growing, locally invasive, very rarely metastasises (<0.5%); "pearly" papule or nodule with rolled border and telangiectasia on sun-damaged skin. SCC: more aggressive; approximately 5% metastasise; arises from actinic keratosis → Bowen's disease (SCC in situ) → invasive SCC. SCC on the lip or ear carries highest metastasis risk.

Transplant patients — 65-100× SCC risk

Solid organ transplant recipients on long-term immunosuppression (particularly ciclosporin) have a 65-100 fold elevated SCC risk — making skin cancer the most common cancer affecting transplant recipients. Regular annual dermatology review and sun protection are mandatory in this group.

Mohs surgery — >99% cure for BCC

Mohs micrographic surgery — serial excision with immediate microscopic margin analysis — achieves cure rates of >99% for primary BCC and >95% for recurrent BCC, while maximising tissue conservation. The gold standard for facial or high-risk BCC.

Cemiplimab and pembrolizumab — advanced SCC

For locally advanced or metastatic cutaneous SCC: cemiplimab (Libtayo, PD-1 inhibitor) achieves approximately 47% objective response rates; pembrolizumab is an approved alternative. These immune checkpoint inhibitors have transformed the previously limited treatment landscape for advanced NMSC.

Key statistics

5-6M

estimated NMSC cases/year in the US alone (most worldwide unreported)

CDC/WHO

most common cancer type globally

WHO

~50K

SCC deaths/year globally — 75% of skin cancer mortality

WHO

65-100×

elevated SCC risk in solid organ transplant recipients

WHO/ECDC

>99%

BCC cure rate with Mohs micrographic surgery

WHO/AAD

~5%

SCC metastasis rate (higher for lip/ear location)

WHO

NMSC types and distribution — global proportion and behaviour

Source: WHO/AAD. BCC vastly more common but SCC accounts for most NMSC deaths.

Glossary of key terms

Basal cell carcinoma (BCC)
WHO/AADArises from basal layer keratinocytes — the most common cancer in humans. Characterised by locally invasive growth (can destroy adjacent structures including bone, eye, nose) but rarely metastasises (<0.5%). Types: nodular (most common — pearly, translucent nodule with telangiectasia); superficial (flat, scaly); morphoeic/sclerosing (scar-like, ill-defined borders — highest recurrence risk). Driven by UV exposure and hedgehog signalling pathway mutations (PTCH1 gene).

Squamous cell carcinoma (SCC)
WHO/ECDCArises from suprabasal keratinocytes. Risk: approximately 5% metastasize (higher for tumours >2cm, poorly differentiated, perineural invasion, immunosuppressed hosts, lip/ear location). Precursor lesions: actinic keratosis (rough, scaly, sun-damaged skin — risk of SCC transformation approximately 0.025-0.1% per lesion per year, but cumulatively significant with many lesions); Bowen's disease (SCC in situ — full-thickness keratinocyte dysplasia without invasion). Caused by UV radiation, HPV (anogenital SCC), chronic wounds (Marjolin's ulcer), ionising radiation, arsenic.

Actinic keratosis (AK)
WHO/AADPrecancerous UV-damaged epidermal lesions — rough, scaly, pink-red macules or papules on sun-exposed skin (scalp, face, dorsal hands, forearms, lips). May progress to invasive SCC. Field treatment: photodynamic therapy (PDT); topical 5-fluorouracil; imiquimod; diclofenac; tirbanibulin. Individual lesion treatment: cryotherapy; curettage.

Mohs micrographic surgery
AAD/BCSCA specialised surgical technique for high-risk or cosmetically sensitive NMSC — particularly BCC: tumour removal followed by immediate frozen-section histological analysis of the excised specimen's margins. If positive margins detected: further excision in that specific area only. Process repeated until clear margins confirmed. Achieves >99% cure rates for primary BCC, maximum tissue conservation. Suitable for: facial BCC, recurrent BCC, morphoeic BCC, any NMSC in difficult anatomical sites.

Cemiplimab (Libtayo)
FDA/EMA 2018A fully human PD-1 monoclonal antibody — the first FDA-approved systemic therapy for advanced cutaneous SCC (September 2018). Objective response rate: approximately 47% in locally advanced or metastatic cSCC. Also approved for BCC (2021) and NSCLC. Given as IV infusion every 3 weeks.

UV protection
WHOWHO recommends: avoid peak UV hours (10am-4pm); use broad-spectrum SPF 30+ sunscreen (SPF50+ in high UV areas); wear UV-protective clothing and wide-brimmed hats; avoid tanning beds (IARC Group 1 carcinogen — classified as definitely carcinogenic to humans in 2009). Sunscreen use reduces SCC risk by approximately 40% and BCC risk by approximately 25% in high-incidence populations.