solitary pigmented lesion on back
Another middle aged white man worried about a solitary pigmented lesion on his back. and with melanoma skin cancer killing well over 2,000 people a year in the UK and rising, fair enough.
let’s take a closer look.
Shape is irregular and colour mixed. These are potentially worrying features, especially as this is a solitary lesion. we would be less worried if there were a dozen others looking very similar. What will the dermoscope reveal?
The very well defined border is confirmed as is the mixed colour. What the dermoscope clarifies is that there are large numbers of comedo like openings and milia like cysts here. These are very characteristic of a seborrhoiec keratosis, a harmless skin lesion that can mimic the potentially lethal melanoma. We also see crypts here and a hint of ‘fat fingers/cerebriform’ appearance. There are no signs of reticular pigment network, aggregated globules or other features of a melanocytic lesion.
In view of the many positive features of a benign seborrhoiec keratosis we can discount the variable colour. If the lesion is not melanocytic, it cannot be a melanoma. Beginners at dermoscopy often ‘freak out’ when they see a bit of out of focus blue/.grey haze in this sort of lesion: relax, it is very common and doesn’t matter. Blue grey veil is only sinister when seen in a melanocytic lesion. This is a non melanocytic lesion.
A safe diagnosis of benign seborrhoiec keratosis can be made and the patient reassured and advised.