A male patient was referred with what turned out to be a BCC on the left arm. He had worked outdoors and had extensive skin damage. A thorough skin examination revealed an irregular pigmented lesion on the chest wall. This had been present for many years with no obvious history of recent growth.
Dermoscopy showed asymmetry and irregular grey structures (in the circle).
Dermoscopy - Introduction, Terminology and Structures
A document to help you understand the dermoscopic descriptions used in this blog.
Dermoscopy Algorithm
To help you work through dermoscopic cases.
More grey structures (arrows). As you will see from the algorithm, asymmetry plus grey structures is one of the red flags. Histology showed a lentigo maligna melanoma with regression.
It is likely that the area of regression is the area in the blue rectangle, which going back to the clinical image is the area highlighted by the blue arrow. The recommended wide excision was marked as 1 cm from the edge of clinically regressing margin.
A normal looking naevus that is not growing is nearly always going to be benign. However, be aware of the suspicious looking lesion (this was asymmetrical with an irregular border and had variation in colour) with no obvious history of change - thin melanoma's can grow very slowly, and those that are regressing may appear to be getting smaller.
Images copyright of South Tees Foundation Trust.
