Ink spot lentigos can masquerade as melanomas. Dermoscopy and excision may be needed to make an accurate diagnosis.
A 30-year-old man presented for examination of a concerning lesion on his upper back. The darkly pigmented lesion was noticed by his partner. He was systemically well with no major comorbidities and no previous history of skin cancers. He admitted to frequent sunburns after brief sun exposure and occasional blistering sunburns in the past. The lesion on his back had caused concern because of its unusual appearance, dark colour and irregular border.
The patient had fair skin and fair hair. On examination, there were numerous moles, freckles and other lentigines on sun-exposed areas of his skin. There was a darkly pigmented lesion (4 x 2 mm) on his central upper back (Figures 1a and b). Dermoscopy showed a darkly pigmented macule with a focally thickened pigment network with holes (Figure 1c).