title: Dermoscopic patterns of melanoma metastases: interobserver consistency and accuracy for metastasis recognition.
abstract: BACKGROUND
  Cutaneous metastases of malignant melanoma (CMMM) can be confused with other skin lesions. Dermoscopy could be helpful in the differential diagnosis.
  
  
  OBJECTIVE
  To describe distinctive dermoscopic patterns that are reproducible and accurate in the identification of CMMM.
  
  
  METHODS
  A retrospective study of 146 dermoscopic images of CMMM from 42 patients attending a melanoma unit between 2002 and 2009 was performed. Firstly, two investigators established six dermoscopic patterns for CMMM. The correlation of 73 dermoscopic images with their distinctive patterns was assessed by four independent dermatologists to evaluate the reproducibility in the identification of the patterns. Finally, 163 dermoscopic images, including CMMM and nonmetastatic lesions, were evaluated by the same four dermatologists to calculate the accuracy of the patterns in the recognition of CMMM.
  
  
  RESULTS
  Five CMMM dermoscopic patterns had a good interobserver agreement (blue naevus-like, naevus-like, angioma-like, vascular and unspecific). When CMMM were classified according to these patterns, correlation between the investigators and the four dermatologists ranged from κ = 0.56 to κ = 0.7. In total, 71 CMMM, 16 angiomas, 22 blue naevi, 15 malignant melanomas, 11 seborrhoeic keratoses, 15 melanocytic naevi with a globular pattern and 13 pink lesions with a vascular pattern were evaluated according to the previously described CMMM dermoscopy patterns, showing an overall sensitivity of 67.9% (range 54.9-76%) and a specificity of 79.9% (range 68.5-93.5%) for the diagnosis of CMMM.
  
  
  CONCLUSIONS
  Five dermoscopic patterns of CMMM with good interobserver agreement obtained a high sensitivity and specificity in the diagnosis of metastasis, with the accuracy varying according to the experience of the observer.
authors.affiliation: Hospital Clínic i Provincial de Barcelona, Unitat de Melanoma, IDIBAPS, Universitat de Barcelona, Barcelona, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Costa
authors.forename: K
authors.initials: K
authors.lastname: Ortiz-Ibañez
authors.forename: G
authors.initials: G
authors.lastname: Salerni
authors.forename: V
authors.initials: V
authors.lastname: Borges
authors.forename: C
authors.initials: C
authors.lastname: Carrera
authors.forename: S
authors.initials: S
authors.lastname: Puig
authors.forename: J
authors.initials: J
authors.lastname: Malvehy
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D046169:Dermoscopy; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008545:Melanoma / Q000473:pathology* / Q000556:secondary; D008875:Middle Aged; D009362:Neoplasm Metastasis; D015588:Observer Variation; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000473:pathology*; D055815:Young Adult