Jane M. Grant-Kels, MD, Editor

Giovanni Pellacani, MD, Editor

Caterina Longo, MD, PhD, Editor

In the hands of experienced confocalists, RCM has demonstrated a sensitivity of 68% to 99% and a specificity of 60% to 99%. In different skin cancer centers where RCM is routinely applied for supporting the diagnostic and decisional process, the number of unnecessary biopsies has been reduced up to 60%! At present, there are only 350 RCM devices worldwide being used for research and clinical endeavors. The use of RCM in clinical practice is today largely diffused in Europe, with more than 200 sites (university clinics, hospitals, and private dermatologists), but seeds of interest and practical applications are present and growing also in United States thanks to pioneers and passionate colleagues throughout the country, like New York, Miami, Los Angeles, Connecticut, and many others. The hope of all the authors included herein is that the numbers of clinicians taking advantage of this technology will increase dramatically now that valued CPT codes have been assigned by the American Medical Association in the United States.

RCM has been studied extensively, and there are more than 600 peer-reviewed articles on confocal microscopy, with approximately 500 of those reviewing in vivo skin imaging applications. However, in this issue of Dermatology Clinics , we have dedicated the entire issue to RCM. Herein, we have gathered the world’s experts on RCM to review this topic in-depth, including all the new advances that have been accomplished in the last few years. We start the issue by covering the basics of the technology and how it is used in clinical practice at the bedside. We have also reviewed the fact that in many cases local expertise is still not available on how best to interpret the images; therefore, one of the articles reviews how this technology lends itself to tele-confocal with the images transmitted via the cloud to an expert for their interpretation. Various articles are dedicated to the features we have come to recognize with RCM that help us differentiate various neoplasms, both benign and malignant. Many of these articles delve deeply into the distinguishing features of melanocytic lesions, nonpigmented lesions, epithelial neoplasms, RCM features in various inflammatory diseases, and the exciting new ways Mohs surgeons can take advantage of this technology, including the use of fluorescence confocal microscopy.

All of the guest editors are grateful to our distinguished group of authors who have contributed to this issue dedicated to RCM. We hope that the articles will inspire more dermatologists and clinicians to become confocalists like us!