A pigmented lesion on back

A 75-year-old man consulted for this pigmented lesion on his back.
His skin was heavily sun exposed.
Clinical image is in the lower right corner.
Dermoscopy revealed:
- an atypical reticular network with different colours and disorganization
- a blue structureless area

This lesion was excised and pathology revealed a superficial spreading melanoma.
Breslow index was 0,30 mm.

Blue nevus

Typical blue homogeneous pattern* in favour of a blue nevus.

* synonym: blue structure less pattern

Blue nevus

A 34-year-old woman consulted for a dark blue lesion on her left ankle. The lesion was not enlarging for many years.

Dermoscopy revealed a blue homogenous pattern with hypopigmented area.

The lesion was removed and pathology confirmed the diagnosis of blue nevus.