Bizarre vessels in a hypopigmented nodular melanoma
I don’t have a plain view of this lesion, but the dermoscopy is very instructive.
Taking a holistic view of the lesion, it looks chaotic. In the middle is blood, round the edge from 10 to 7 o’clock there is a grey/blue area with shiny white structures. At the bottom left there is a fairly amorphous/structureless area in which some vessels are circled. Click on the image to enlarge.
Vessels in a hypopigmented/non pigmented melanoma may be the only positive clue. They are described as polymorphous, i.e. of varying and unclassifiable pattern. We may see dotted vessels in melanocytic lesions, benign or malignant.
when we see vessels on dermoscopy, we ask about 3 things
1) what is the morphology of the vessels?
2) what is the distribution of the vessels?
3) what non-vascular features can we see?
Here, we see vessels that are bizzare/unclassifiable in morphology, and highly asymmetrical in distribution. Non vessel features include ulceration, blue/grey structures, shiny white structures and chaos. More than enough evidence for a melanoma.
Another approach to this lesion is to ask -can we prove that it is a specific type of benign lesion, or a BCC? Evidently not. Therefore it is a melanoma by default, as histology proved.
Another approach is the SCOPE mnemonic. This is not an algorithm or scoring system, just a way of helping the observer to take a systematic approach to pattern analysis.
Count the COlours-blue/grey, white and red. 3 colours is one too many
COunt the Patterns. Ulceration/blood, blue/grey haze, shiny white clods/streaks, featureless pink area, irregular vessels-5 patterns. That’s too many.
Edge-trace round the edge and it’s irregular.
melanoma all the way.