DermNet provides Google Translate, a free machine translation service. Note that this may not provide an exact translation in all languages
Author: Naomi Ashman, Dermoscopist, Torbay Skin, Auckland, New Zealand; DermNet New Zealand Editor in Chief Adjunct A/Prof Amanda Oakley, Dermatologist, Hamilton, New Zealand. Created January 2019.
Concentric circles are a specific clue to melanoma on the face (lentigo maligna), but the clue has poor sensitivity as they are rarely present. In a study by Tschandl et al, concentric circles were only found in 4.2% of flat facial melanomas, usually larger lesions . Concentric circles are also referred to as a circle within a circle and the isobar sign.
Concentric circles consist of an asymmetrical pigmented follicular opening with a darker dot located within ostial openings.
Books about skin diseases
© 2022 DermNet New Zealand Trust.
DermNet NZ does not provide an online consultation service. If you have any concerns with your skin or its treatment, see a dermatologist for advice.