Histopathologic correlation in dermoscopy: a micropunch technique.

BACKGROUND Dermoscopy is a simple-to-use, in vivo method for the diagnosis of malignant melanoma and the differential diagnosis of pigmented skin lesions. It uses an immersion technique and optical magnification to visualize structures not visible to the naked eye. The anatomoclinical correlation of dermoscopic with histopathologic findings is important, and while many articles have described different techniques to achieve this goal, no direct correlation with a visual control has been described. We recently developed a micropunch technique that allows for the first time this direct correlation. OBSERVATIONS After applying local anesthesia, the physician makes a superficial round incision using a 1-mm micropunch in the area of interest and leaves the punch in place. The lesion is documented using digital dermoscopy before and after surgery. Using these images, the laboratory technicians can easily visualize the precise site of the punch and its correlation with the initial dermoscopic image, and the sections are chosen in a way that they pass through the punch incision. The punch incision can be easily identified in the histopathologic slides because of its clear-cut borders. Since the punch always stays in place, this technique does not interfere with the interpretation of the slides (eg, measurement of the Breslow thickness). CONCLUSIONS The advantages of our technique are that it is easy to perform by any clinician in any setting after a short setup and training period for the clinician and the laboratory technicians. Unlike with other techniques, the physician need not be present at the laboratory at the moment of the step sectioning. It can be performed in private practice and for many other indications besides pigmented skin lesions. Finally, since this technique allows for the first time a direct correlation between dermoscopic and histopathologic findings, the clinician will be able to "guide" the pathologist and indicate the precise areas of interest or suspicion.