Family MedicineAcademyWritten AKTNotesDermatologyPremalignant skin conditions
Dermatology
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UV-related premalignant lesions; common over age 60 on sun-exposed skin.
Features: Small crusty or scaly spots; colour varies (skin-coloured, pink, brown). Diagnosis is usually clinical.
Management: Topical 5-FU, diclofenac, imiquimod; cryotherapy; curettage and cautery.
Advice: Prevention: sun avoidance and regular sunscreen.
Red flags: Urgent 2-week wait if SCC is suspected, diagnosis is uncertain, or disease is widespread/severe.
Intraepidermal SCC precursor; mainly elderly; about 5-10% risk of invasive SCC if untreated.
Features: Slow-growing red scaly patch (often 10-15 mm) on sun-exposed skin.
Management: Topical 5-FU (typically around 4 weeks), cryotherapy, or excision.
White, firm patches on mucous membranes; strongly linked to smoking. Roughly 1% risk of malignant change to SCC.
Features: Diagnosis of exclusion (candida, lichen planus).
Management: Biopsy to exclude SCC; arrange follow-up.
Red flags: Persistent oral white patches, especially with induration or ulceration, need urgent assessment for malignancy.
Reticulated erythema and hyperpigmentation from chronic infrared heat (hot water bottle, fire, laptop). Can progress to SCC if the heat source continues unchecked.
Management: Stop the heat source; refer if nodular change or suspected SCC.
Chronic inflammatory disease, mainly genital/perianal; more common in older women. About 5% lifetime risk of SCC.
Features: White sclerotic patches, intense itch, dyspareunia or dysuria; scarring risk. Usually clinical diagnosis; biopsy if atypical or cancer suspected.
Management: Potent topical steroids and emollients; long-term follow-up.
Red flags: Suspected SCC, treatment failure, diagnostic doubt, or paediatric lichen sclerosus.