As the prevalence of melanoma rises and clinical and histopathologic evaluation of pigmented lesions becomes more difficult, noninvasive methods to aid in the assessment of skin lesions are in great demand. The methods, benefits, and limitations of adhesive patch biopsy, electrical impedance spectroscopy (EIS), multispectral imaging, high-frequency ultrasonography (HFUS), optical coherence tomography (OCT), and reflectance confocal microscopy (RCM) in the detection of skin cancer are discussed in this review. Adhesive patch biopsy improves sensitivity and specificity for melanoma diagnosis without the trade-off of increased sensitivity for poorer specificity found in other skin cancer detection techniques, such as EIS and multispectral imaging. EIS and multispectral imaging give objective data based on computer-assisted diagnosis to help with the choice to biopsy and/or remove an unusual melanocytic lesion. HFUS may be beneficial for determining skin tumour depth and identifying surgical boundaries, but further research is needed to verify its accuracy in detecting skin cancer. OCT and RCM give greater resolution of skin tissue and have been used to improve the accuracy of skin cancer diagnosis, as well as to monitor the response to nonsurgical therapies for skin malignancies and to determine tumour margins and recurrences.
These innovative approaches to skin cancer evaluation provide potential for dermatologists, but they are contingent on the individual dermatologist’s comfort, competence, and willingness to engage in noninvasive procedures training and implementation. Although histopathologic diagnosis remains the gold standard for skin cancer evaluation, these noninvasive methods may play a role in the supplementary assessment of skin malignancies.