Patterns and pitfalls: Dermoscopic differentiation of early-stage mycosis fungoides, atopic dermatitis, and psoriasis

Balan K., Lallas A., AKDOĞAN N.

Journal of the American Academy of Dermatology, 2026 (SCI-Expanded, Scopus) identifier identifier

  • Publication Type: Article / Article
  • Publication Date: 2026
  • Doi Number: 10.1016/j.jaad.2025.12.049
  • Journal Name: Journal of the American Academy of Dermatology
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, CINAHL, EMBASE, MEDLINE, Nature Index
  • Keywords: atopic dermatitis, dermoscopy, mycosis fungoides, psoriasis, ultraviolet mode, vascular pattern
  • Hacettepe University Affiliated: Yes

Abstract

Background Mycosis fungoides (MF), psoriasis (Pso), and atopic dermatitis (AD) may present with overlapping clinical features, which may lead to delayed diagnosis. Dermoscopy, including ultraviolet (UV) mode, can help distinguish disease-specific patterns. Objective To compare dermoscopic and UV features of early-stage MF, Pso, and AD. Methods In this prospective cohort study, 159 patients (MF: 55, Pso: 53, AD: 51) were examined with dermoscopy and UV mode. Vascular patterns, scale features, background color, structureless areas, and vessel density per mm2 were analyzed. Group differences were assessed with chi-square/Fisher's exact tests or ANOVA/Welch ANOVA, using Bonferroni/Games–Howell corrections. Results MF showed linear and spermatozoa-like vessels, scaling along skin furrows, focal structureless areas, and the lowest vessel density. Pso was defined by uniformly distributed dotted vessels on a bright-red background with diffuse scaling and the highest vessel density. AD showed mainly dotted vessels with additional linear vessels, along with yellow-orange scale, ulceration, dystrophic hairs, and intermediate vessel density. UV imaging improved visualization of structureless areas and scaling edges. Limitations Single-center design, modest sample size, and restriction to early stages may limit generalizability. Conclusion Dermoscopy with UV mode shows distinct features in MF, Pso, and AD. This approach may support early, noninvasive differentiation.