Melanoma tumour cells transmit electricity somewhat differently from normal healthy cells, and the effect of this can be detected using electrical impedance spectroscopy. Reference measurements taken in the past allow the system to compare with those and point to suspect melanoma during the exam.
The physician simply moistens the skin over the lesion, wipes off, and measures by placing the pen tip against the lesion. The table-top touchscreen display then provides a spectrogram of the readings and how out of normal range they are. Having this information dermatologists may then be able to form a better idea of whether to move toward biopsy of the suspect lesion.