title: Significance of dermoscopic patterns in detecting malignant melanoma on acral volar skin: results of a multicenter study in Japan.
abstract: OBJECTIVE
  To determine diagnostic variables such as sensitivity and specificity of the major dermoscopic patterns observed in melanocytic lesions on acral volar skin, with particular attention to the significance of the parallel ridge pattern and irregular diffuse pigmentation in detecting acral melanoma.
  
  
  METHODS
  Multicenter, retrospective study.
  
  
  METHODS
  University hospitals in Japan.
  
  
  METHODS
  Patients with melanocytic lesions on acral volar skin. A total of 712 melanocytic lesions (103 malignant melanomas, including 36 in situ lesions, and 609 melanocytic nevi) were consecutively collected from the files of 3 hospitals. Diagnoses of all the lesions had been determined histopathologically.
  
  
  METHODS
  Dermoscopic examination.
  
  
  METHODS
  The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of the major dermoscopic patterns seen in benign and malignant melanocytic lesions on acral volar skin.
  
  
  RESULTS
  The parallel ridge pattern and irregular diffuse pigmentation showed extremely high specificity (99.0% and 96.6%, respectively) and very high negative predictive value (97.7% and 97.5%, respectively) in malignant melanoma. For melanoma in situ, the positive predictive value and diagnostic accuracy of the parallel ridge pattern were significantly higher than those of irregular diffuse pigmentation (P = .009 and P = .006, respectively). In melanocytic nevi, the specificity and positive predictive value of the parallel furrow pattern and/or the latticelike pattern were found to be very high (93.2% and 98.3%, respectively).
  
  
  CONCLUSIONS
  Dermoscopy is immensely helpful in differentiating malignant melanomas from melanocytic nevi on acral volar skin. Moreover, the parallel ridge pattern aids in detecting acral melanomas in early, curable stages.
authors.affiliation: Department of Dermatology, Shinshu University School of Medicine, Matsumoto 390-8621, Japan. tosaida@hsp.md.shinshu-u.ac.jp
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Saida
authors.forename: Atsushi
authors.initials: A
authors.lastname: Miyazaki
authors.forename: Shinji
authors.initials: S
authors.lastname: Oguchi
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ishihara
authors.forename: Yoriko
authors.initials: Y
authors.lastname: Yamazaki
authors.forename: Sumio
authors.initials: S
authors.lastname: Murase
authors.forename: Shusuke
authors.initials: S
authors.lastname: Yoshikawa
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Tsuchida
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kawabata
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Tamaki
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008499:Medical Records; D008545:Melanoma / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology; D008853:Microscopy / Q000379:methods*; D008875:Middle Aged; D009508:Nevus, Pigmented / Q000175:diagnosis / Q000453:epidemiology / Q000473:pathology; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology