Globule or comedo-like opening? One structure, two diagnoses

SK_vs_Melanoma.mp4

  • Comedo-like opening = keratin plug in a crater: depressed, angulated, yellow keratin

  • Atypical globule = flat pigment: variable in size, shape and colour, asymmetric, peripheral

  • Hunt for melanoma clues anywhere: pigment network, blue-white veil, irregular globules, streaks, blue-black sign

Pearl: One melanoma clue outweighs any number of SK features.

💬 Your turn

  1. Your rule: When dark round structures could be globules or comedo-like openings, what tips the balance for you? Side light, yellow keratin, or something else?

  2. Show us your trap: Post an SK-like melanoma, or an SK that fooled you.

  3. Myth or fact? "Milia-like cysts rule out melanoma." Answer below; the explanation follows on Friday.

🎓 Go deeper

SK mimics and other diagnostic traps are covered in depth in our on-demand courses: Masterclass 2026 · International Dermoscopy Course

Refs: Carrera C et al. JAMA Dermatol 2017;153:544–551 · Braun RP et al. Arch Dermatol 2002;138:1556–1560