Pigmented Macule on the Foot

An irregular pigmented macule with a superficial ulceration and brown haemorrhagic crusts was observed on the left plantar near the heel
An irregular pigmented macule with a superficial ulceration and brown haemorrhagic crusts was observed on the left plantar near the heel

A 55-year-old woman presented with a non-healing, painless pigmented macule with a superficial ulceration on the left planta, which she said had been there for 6 months. She could not recall any history of trauma and did not report any family history of cutaneous diseases.

What’s the diagnosis ?