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Melanoma — SCE Dermatology MCQ

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ModerateSkin CancerMelanomaSCE Dermatology

A 60-year-old man has a melanoma in situ (lentigo maligna type) on his left cheek. What is the recommended excision margin?

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Correct answer: D5-10 mm with aim of complete histological clearance

The correct answer is D, 5-10 mm with aim of complete histological clearance. UK guidance (British Association of Dermatologists, published in the British Journal of Dermatology) specifies that melanoma in situ, including the lentigo maligna subtype, should be excised with 5-10 mm clinical margins, with the surgical goal being complete histological clearance rather than a fixed numerical margin. This wider range (rather than the older 2 mm or 5 mm figures used for benign lesions or invasive melanoma protocols) reflects the recognised subclinical extension of atypical melanocytes beyond the visible lesion, particularly on chronically sun-damaged facial skin where lentigo maligna arises. Minimum clearance from all margins must be histologically confirmed, and any positive or close margin mandates re-excision; staged excision or Mohs-type techniques are often used on the face to balance clearance with cosmesis.

Reference: https://www.nice.org.uk/guidance/conditions-and-diseases/skin-conditions