title: Clinical and dermoscopic characteristics of amelanotic melanomas that are not of the nodular subtype.
abstract: BACKGROUND
  Amelanotic melanomas remain challenging to diagnose.
  
  
  OBJECTIVE
  To analyze and describe the clinical and dermoscopic characteristics of amelanotic melanomas that are not of the nodular subtype.
  
  
  METHODS
  We conducted a retrospective review of 20 consecutively diagnosed amelanotic melanomas. The clinical and dermoscopic images of pathologically confirmed amelanotic melanomas that were not of the nodular subtype were analyzed. In addition, the clinical diagnosis and the reasons why these lesions were biopsied were examined.
  
  
  RESULTS
  All 20 amelanotic melanomas were erythematous and lacked any of the clinical ABCD features commonly attributed to melanoma. The lesions appeared clinically to be relatively symmetric with regular borders and manifesting a circular to oval morphology. Dermoscopically, all lesions manifested polymorphous vascular pattern.
  
  
  CONCLUSIONS
  Amelanotic melanomas that are not of the nodular subtype often present as clinically symmetric erythematous lesions. Therefore, it is important to consider AMs in the differential diagnosis of isolated and persistent erythematous outlier lesions, even if they are symmetric in appearance. Additionally, the presence of a polymorphous vascular pattern seen with dermoscopy can facilitate in correctly identifying these melanomas.
authors.affiliation: Department of Dermatology, Memorial Sloan-Kettering Cancer Center, New York, NY, USA.
authors.forename: N
authors.initials: N
authors.lastname: Jaimes
authors.forename: R P
authors.initials: RP
authors.lastname: Braun
authors.forename: L
authors.initials: L
authors.lastname: Thomas
authors.forename: A A
authors.initials: AA
authors.lastname: Marghoob
mesh_terms: D046169:Dermoscopy / Q000379:methods*; D006801:Humans; D018328:Melanoma, Amelanotic / Q000175:diagnosis / Q000473:pathology*; D012878:Skin Neoplasms / Q000175:diagnosis / Q000473:pathology*