• Age (<50 and location on trunk has better prognosis)

• Family history (a patient with a dysplastic naevus with two relatives having malignant melanoma has a 300 time increased chance of having a malignant melanoma)

• Ask the patient:

• Remember MacKie’s four independent risk factors for melanoma: freckles, moles (Fig. 194.1), atypical naevi (Fig. 194.2) and a history of severe sunburn.

• Irregular and asymmetrical, with a fuzzy border where the pigment appears to be leaking into the surrounding skin (Fig. 194.3). (The American Cancer Society mnemonic to suspect malignancy in a mole is ABCDE: asymmetry, border irregular, colour variegation and diameter >6 mm; elevated lesions are more suspicious.)