Compared with melanoma (where usually the ki67 proliferation index is >10% of melanocytes), SN tend to have a much lower Ki-67 proliferative index (<2% of melanocytes) and a lower dermal/epidermal count ratio (0.25 SN vs. 0.94 MM) (68, 73–75). Here, MKI67 is linked to Miyoshi myopathy.