Actinic KeratosisRob Sheehan-Dare

Leeds Centre for Dermatology

Pre-Cancerous LesionsActinic Keratoses Intra-epithelial Squamous Cell CarcinomaLentigo maligna

Skin CancerBasal Cell CarcinomaSquamous Cell CarcinomaMelanomaLymphoma

What are Actinic keratoses?

Epidermal dysplasiaAssociated with UV exposure

Sun exposed sitesElderlyOutdoor occupationsWarmer climatesLighter skin typesImmunosuppression

What are Actinic keratoses?

HistologicallyEpidermal cell disorganisationAcanthosisReduced granular layerParakeratosisHyperkeratosis

What is risk of malignancy?

?Less than 1:1000 per yearIncreased by

ImmunosuppressionIncreased numbers of lesionsCo-factors (radiation, exposure to tar)Prior Squamous cell carcinoma

Some lesions resolve spontaneouslyMost SCC’s are well differentiated

What do they look like?

ClinicallyAdherent scale (variable but always)Erythema (often)Light pigmentation (sometimes)Merge with surrounding skinUsually not indurated

Diagnostic difficulties

Cutaneous hornHypertrophic actinic keratosesInflammatory lesions

Often in immunosuppressed

What to treat

Lesions in immunosuppressed patientsLesions at high risk sites (e.g. lip)Where previous history of SCCInflamed Actinic keratosesLesions in younger age groupSymptomatic lesions

How to treat

CryotherapyCurettage & cautery5-fluorouracil creamDiclofenac gelImiquimod creamPhotodynamic therapy

Cryotherapy

Destruction by cold injury Cotton bud or cryospray 20-30 second freeze Moderate pain Immediate blistering Heals in 10 days

Suitable for small/few lesions Suitable where compliance poor

Curettage and cautery

Physical removal/thermal injury Requires local anaesthesia Moderate pain Eschar Heals in 10 days

Suitable for solitary/few lesions Suitable for cryo resistant lesions Suitable for hyperkeratotic lesions Suitable where histology required

5-fluorouracil cream

Inhibits DNA synthesis by inactivating thymidine synthase

4 weeks treatment Inflammatory reaction (moderate-severe) Little pain Interrupted treatment may be required

Suitable for multiple/extensive lesions Suitable for compliant patients

Diclofenac gel

Inhibits Cyclo-oxygenase (COX-2)8 weeks treatmentMild-moderate inflammatory reactionNo painLong term benefits uncertain

Suitable where intolerance to other treatment

Imiquimod cream

Toll-like receptor 7 agonist induces apoptosis

4-8 weeks treatment Inflammatory reaction (moderate-severe)Little pain Interrupted treatment may be required

Suitable for multiple/extensive lesionsSuitable for compliant patients

Photodynamic therapy

ALA induced protoporphyrin IX synthesis sensitizes cells to photodynamic effect

1-2 prolonged treatments Moderate pain Inflammatory reaction (moderate-severe) Heals in 10 days

Suitable for multiple/extensive lesions Suitable where compliance poor

Treatment summary

Cryotherapy small/few lesions 5-fluorouracil larger/multiple lesions

Curettage for hyperkeratotic lesions Solaraze for patients with poor tolerance

Imiquimod cream or PDT for resistant lesions

““They look benign , but keep out of the sun”They look benign , but keep out of the sun”