Abstract
Skin cancer is a global health challenge, as an estimated 2-3 million skin cancers occur globally, costing $8.1 billion USD in the just the US. Incidence and healthcare costs have been steadily increasing as patients and physicians still lack the pattern recognition capabilities to identify skin cancers early. Even dermatologists, experts at skin cancer identification, misevaluate half of all melanomas. Current tools available to patients and physicians are limited and include skin cancer pictures in dermatology atlases, dermatoscopes for highly trained dermatologists, and various smartphone apps without FDA approval and limited accuracy. The gold standard for diagnosis requires lesion removal and microscopic analysis by a trained pathologist. There is a significant need for an accurate, fast, and affordable tool for screening that complements visual identification. This research establishes user needs for dermatologists, primary care physicians, and patients, reviews clinical and biological challenges, and explores the design and testing of bioimpedance-based tool that could improve melanoma, basal cell carcinoma, and squamous cell carcinoma identification in the clinic and in the home. We identified that balancing electrode coverage, electrode spacing, and electrode shape can drive current density magnitude distribution down to deeper layers of skin. We also identified that all three dominant skin cancers begin in the very thin epidermis (about 100 micrometers thick), allowing technologists to develop increasingly small sensors that can detect electrical properties of skin cancers at their earliest stages.