title: Evaluation of electrical impedance spectroscopy as an adjunct to dermoscopy in short-term monitoring of atypical melanocytic lesions.
abstract: BACKGROUND
  Early detection of melanoma is vital for treatment outcome and survival. Short-term sequential digital dermoscopic monitoring (ST-SDDM) involves the capture and assessment of dermoscopic images of one or more atypical melanocytic lesions (AMLs), at baseline and after four months, in order to detect early morphologic changes. Electrical impedance spectroscopy (EIS) is a diagnostic tool with high sensitivity for the detection of malignant melanocytic lesions.
  
  
  OBJECTIVE
  The aim of this study was to assess whether EIS, in addition to ST-SDDM, could improve the selection of AMLs requiring surgery.
  
  
  METHODS
  In this retrospective descriptive study, 22 AMLs in 19 patients were monitored with both ST-SDDM and EIS. A modified EIS decision-making algorithm was established. AMLs were excised if any dermoscopic changes were seen and/or if the EIS score had increased significantly at follow-up. Statistical analyses were made including sensitivity, specificity, PPV and NPV.
  
  
  RESULTS
  A total of seven lesions (32%) were excised. Four lesions (57%) were excised solely because of dermoscopic changes including a 0.4 mm-thick melanoma and three benign nevi. Three benign lesions (43%) were excised because of increased EIS scores without any dermoscopic changes. The EIS scores at follow-up showed high variability as compared to the initial scores.
  
  
  CONCLUSIONS
  The addition of EIS to ST-SDDM did not identify additional malignant lesions. There was no correlation between dermoscopic changes seen with ST-SDDM and increased EIS scores. Three histopathologically benign lesions were needlessly excised. Moreover, the low reproducibility and the possible interoperator variability of the method raised concerns.
authors.affiliation: Department of Dermatology and Venereology, Sahlgrenska University Hospital and Institute of Clinical Sciences at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Hannah
authors.initials: H
authors.lastname: Ceder
authors.affiliation: Department of Dermatology and Venereology, Sahlgrenska University Hospital and Institute of Clinical Sciences at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Alexandra Sjöholm
authors.initials: AS
authors.lastname: Hylén
authors.affiliation: Department of Dermatology and Venereology, Sahlgrenska University Hospital and Institute of Clinical Sciences at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Ann-Marie Wennberg
authors.initials: AW
authors.lastname: Larkö
authors.affiliation: Department of Dermatology and Venereology, Sahlgrenska University Hospital and Institute of Clinical Sciences at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
authors.forename: John
authors.initials: J
authors.lastname: Paoli
keywords: atypical melanocytic lesion; dermoscopy; electrical impedance spectroscopy; melanoma; short-term monitoring