title: Dermoscopic evaluation of amelanotic and hypomelanotic melanoma.
abstract: OBJECTIVE
  To determine the predictive dermoscopic features of amelanotic and hypomelanotic melanoma.
  
  
  METHODS
  A total of 105 melanomas (median Breslow thickness, 0.76 mm), 170 benign melanocytic lesions, and 222 nonmelanocytic lesions lacking significant pigment (amelanotic, partially pigmented, and light colored) were imaged using glass-plate dermoscopy devices and scored for 99 dermoscopic features. Diagnostic models were derived from and tested on independent randomly selected lesions.
  
  
  METHODS
  Predominantly hospital-based clinics from 5 continents.
  
  
  METHODS
  Sensitivity, specificity, and odds ratios for individual features and models for the diagnosis of melanoma and malignancy.
  
  
  RESULTS
  The most significant negative predictors of melanoma were having multiple (>3) milialike cysts (odds ratio, 0.09; 95% confidence interval, 0.01-0.64), comma vessels with a regular distribution (0.10; 0.01-0.70), comma vessels as the predominant vessel type (0.16; 0.05-0.52), symmetrical pigmentation pattern (0.18; 0.09-0.39), irregular blue-gray globules (0.20; 0.05-0.87), and multiple blue-gray globules (0.28; 0.10-0.81). The most significant positive predictors were having a blue-white veil (odds ratio,13; 95% confidence interval, 3.9-40.0), scarlike depigmentation (4.4; 2.4-8.0), multiple blue-gray dots (3.5; 1.9-6.4), irregularly shaped depigmentation (3.3; 2.0-5.3), irregular brown dots/globules (3.2; 1.8-5.6), 5 to 6 colors (3.2; 1.6-6.3), and predominant central vessels (3.1; 1.6-6.0). A simple model distinguishing melanomas from all nonmelanomas had a sensitivity of 70% and a specificity of 56% in the test set. A model distinguishing all malignant lesions from benign lesions had a sensitivity of 96% and a specificity of 37%. Conclusion Although the diagnostic accuracy of dermoscopy for melanoma lacking significant pigment is inferior to that of more pigmented lesions, features distinguishing the former from benign lesions can be visualized on dermoscopic evaluation.
authors.affiliation: Faculty of Medicine, University of Sydney, Sydney Melanoma Diagnostic Centre, Royal Prince Alfred Hospital, Camperdown, NSW 2050, Australia. scott.menzies@email.cs.nsw.gov.au
authors.forename: Scott W
authors.initials: SW
authors.lastname: Menzies
authors.forename: Juergen
authors.initials: J
authors.lastname: Kreusch
authors.forename: Karen
authors.initials: K
authors.lastname: Byth
authors.forename: Maria A
authors.initials: MA
authors.lastname: Pizzichetta
authors.forename: Ashfaq
authors.initials: A
authors.lastname: Marghoob
authors.forename: Ralph
authors.initials: R
authors.lastname: Braun
authors.forename: Josep
authors.initials: J
authors.lastname: Malvehy
authors.forename: Susana
authors.initials: S
authors.lastname: Puig
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Argenziano
authors.forename: Iris
authors.initials: I
authors.lastname: Zalaudek
authors.forename: Harold S
authors.initials: HS
authors.lastname: Rabinovitz
authors.forename: Margaret
authors.initials: M
authors.lastname: Oliviero
authors.forename: Horacio
authors.initials: H
authors.lastname: Cabo
authors.forename: Verena
authors.initials: V
authors.lastname: Ahlgrimm-Siess
authors.forename: Michelle
authors.initials: M
authors.lastname: Avramidis
authors.forename: Pascale
authors.initials: P
authors.lastname: Guitera
authors.forename: H Peter
authors.initials: HP
authors.lastname: Soyer
authors.forename: Giovanni
authors.initials: G
authors.lastname: Ghigliotti
authors.forename: Masaru
authors.initials: M
authors.lastname: Tanaka
authors.forename: Ana M
authors.initials: AM
authors.lastname: Perusquia
authors.forename: Gianluca
authors.initials: G
authors.lastname: Pagnanelli
authors.forename: Riccardo
authors.initials: R
authors.lastname: Bono
authors.forename: Luc
authors.initials: L
authors.lastname: Thomas
authors.forename: Giovanni
authors.initials: G
authors.lastname: Pellacani
authors.forename: David
authors.initials: D
authors.lastname: Langford
authors.forename: Domenico
authors.initials: D
authors.lastname: Piccolo
authors.forename: Karin
authors.initials: K
authors.lastname: Terstappen
authors.forename: Ignazio
authors.initials: I
authors.lastname: Stanganelli
authors.forename: Alex
authors.initials: A
authors.lastname: Llambrich
authors.forename: Robert
authors.initials: R
authors.lastname: Johr
mesh_terms: D046169:Dermoscopy; D003937:Diagnosis, Differential; D006801:Humans; D008545:Melanoma / Q000473:pathology*; D018328:Melanoma, Amelanotic / Q000473:pathology*; D008954:Models, Biological; D015588:Observer Variation; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000473:pathology*; D012880:Skin Pigmentation