Clinical diagnosis of basal cell (BCC) and squamous cell (SCC) carcinoma subtypes is challenging. There are multiple subtypes of BCC and SCC that can be difficult to distinguish clinically and ideally require different biopsy techniques for optimal histologic analysis and therapeutic decision-making¹. Visual detection of BCC and SCC can be facilitated with the aid of dermoscopy² but determining prior to biopsy whether a lesion is superficial or more deeply invasive is usually not possible. There is a great clinical need to develop new technologies to augment visual skin examination to guide biopsy-decision-making and improve management of lesions suspicious for BCC and SCC. To date, there is no bedside technique available that is low cost, easily applied, quantitative, objective, and capable of overcoming these diagnostic hurdles. EID is a newer non-invasive, quantitative, and objective tool sensitive enough to detect alterations in the electrical properties of skin cancers. The overarching hypothesis of my proposal is that EID can be used to distinguish BCC subtypes and between SCC-in situ, invasive SCC, and inflamed keratosis that cannot be appreciated clinically.
The ""superficial"" form of BCC is confined to the epidermis and can be effectively treated by non-surgical means. The ""nodular"" form of BCC consists of a collection of round tumor cells occupying the upper part of the dermis and can be treated by destruction or surgically depending on its size and location. ""Micronodular"" and ""infiltrative"" forms of BCC consist of smaller aggregates of tumor cells or angulated or stranded tumor cells, respectively, infiltrating the deeper dermis and usually require surgical treatment. Importantly, these invasive subtypes of BCC can present as papules or plaques that cannot reliably be distinguished clinically from nodular or the more superficial subtype of BCC. The superficial form of SCC can resemble BCC, and it is challenging clinically to distinguish this entity from invasive SCC; the former is best biopsied by shave technique while the latter is best biopsied by punch technique to assess depth of invasion³. These histologic changes cannot be reliably appreciated visually and thus distinguishing subtypes of BCC and SCC presents a clinical conundrum. EID technology could contribute to overall clinical assessment by increasing confidence and diagnostic accuracy that will inform biopsy-decision making in patients with lesions suspicious for skin cancer. My research showed EID to be very effective and efficient at diagnosing BCC and SCC. In the BCC study, I obtained a specificity of 88%. Similarly, in the SCC study, I achieved an averaged area under the curve of 0.968, sensitivity of 94.6%, and specificity of 96.9% (Fig.1). In both cases, my results exceed the diagnostic accuracy of using the dermoscope, the clinical gold standard technology.