Chaos & Clues for Pigmented Lesions
Evaluate how many patterns (based on geometric shapes) and colours there are.
- Is there 1 pattern or > 1 pattern?
- If yes, skip to step 2.
- Is there 1 colour or > 1 color?
- If yes, skip to step 2.
What the colors means…
- Melanin:
- Black: Melanin in the stratum corneum)
- Brown: Must be abrupt change (dark/light brown)
- Dark brown: Melanin in the epidermis (dense)
- Light brown: Melanin in the epidermis (delicate)
- Gray: Melanin in the papillary dermis
- Blue: Melanin in the reticular dermis
- Orange: Combination of melanin and keratin, also serum crust
- Keratin: Yellow, white (under stratum corneum)
- Collagen: White (sclerosis), white could also mean absence of melanin
- Blood: Red, or purple if poorly oxygenated
Chaos:
- Chaos is defined as asymmetry of structure (i.e. pattern) and/or colour. Irregularity of shape does not matter.
Is there symmetry based on pattern or colour?
- If 1 pattern only → Symmetry based on colour only
- If 1 colour only → Symmetry based on patterns only
- If 1 colour + 1 pattern only → Symmetrical by convention
If there is no Chaos (i.e. symmetrical)…
- No intervention (move to next lesion on TBSE)
(A) There are 9 dermoscopic clues to malignancy:
(B) Can the clues you’ve identified be explained by Seborrhoeic Keratosis?
- Clues to seborrheic keratosis:
- Multiple orange clods
- Multiple white clods
- Thick curvy lines
- Sharply demarcated border over the full periphery
- Multiple grouped similar lesions