Question

An elderly man has a long-standing mole over the face that is increasing in size and showing irregular borders. What is the most likely diagnosis?

• A. Superficial spreading melanoma
• B. Lentigo maligna melanoma
• C. Acral melanoma
• D. Nodular melanoma

Hint:

A long-standing mole that changes slowly then grows, with irregular borders, points to the commonest melanoma subtype.

Answer 1

The Correct Option is A

Sort the four melanoma subtypes by their signature stories. Acral lentiginous melanoma sits on palms and soles, so it is out for a facial lesion. Nodular melanoma is a fast-growing blue-black papule with no long radial-growth phase, which clashes with a long-standing mole, so drop it. That leaves superficial spreading versus lentigo maligna melanoma. Superficial spreading melanoma is the commonest type (around $70\%$) and the prototype of a pre-existing naevus that creeps along for years and then accelerates, developing the irregular, asymmetric border the stem describes. Lentigo maligna melanoma is tempting because of the elderly, sun-exposed face, but it classically begins as a flat variegated macule on de novo sun-damaged skin rather than as a changing mole. Given the emphasis on a transforming long-standing naevus with irregular borders, the keyed answer is superficial spreading melanoma.