Integrating Electrical Impedance Spectroscopy into Clinical Decisions for Pigmented Skin Lesions Improves Diagnostic Accuracy: A Multitiered Study

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Graham H Litchman
Justin W Marson
Ryan M Svoboda
Darrel S Rigel


Electrical Impedance Spectroscopy, Melanoma, Melanoma Diagnosis, Number-Needed-To-Biopsy


Introduction: The number-needed-to-biopsy (NNB) metric measures the efficiency of a clinician’s ability to accurately diagnose and recommend pigmented skin lesions (PSLs) for biopsy for suspected melanomas. Electrical impedance spectroscopy (EIS) is a non-invasive technique that measures differences in resistance between healthy and cancerous skin cells, intended as an aid to enhance diagnostic accuracy.

Methods: Dermatology clinicians of three distinct groups (residents, physician assistants/nurse practitioners, and practicing dermatologists) were evaluated on their ability to accurately recommend suspect PSLs for biopsy before and after the integration of EIS data.

Results: All three groups had a reduction in NNB after the inclusion of EIS. Instances of missed biopsies for malignant melanoma were significantly reduced with simultaneous significant reductions in unnecessary biopsies for benign lesions. There was a material improvement of biopsy selection for PSLs having clinically challenging features. EIS also greatly improved the diagnostic acumen of clinicians whose assessments were less accurate than their peers prior to EIS incorporation.

Conclusions: The integration of EIS technology into the PSL biopsy decision was demonstrated to be effective in significantly enhancing clinician NNB and more accurate PSL biopsy selection.


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