A 60-year-old man consulted for this black-blue tumor on his back.

Patient did not know when this lesion appeared.

Dermoscopy revealed a homogenous blue pattern with whiter areas.

Two diagnosis were suspected:

- blue nevus

- melanoma

This lesion was excised and pathology revealed a blue nevus with fibrous involution

Whitish area

A 17-year-old girl presented a pigmented lesion with a lateral  depigmentation.

Dermoscopy  revealed a globular pattern associated with a whitish structureless area. On this whitish area some vessels were observed. There were no signs of peppering.

This lesion was excised and pathology revealed a benign dermal melanocytic nevus with a fibrous involution.

Whitish structureless area can be observed in:

• fibrous involution
• after traumatism
• in case of regression (with peppering)