Combined Use of Ex Vivo Dermoscopy and Histopathology for the Diagnosis of Melanocytic Tumors.

Dermoscopy can be applied to fixed tissues, and dermoscopic patterns correlate with microscopic findings. Data on the influence of ex vivo dermoscopy on pathologic diagnosis of melanocytic lesions are limited. Therefore, we aimed to determine whether this technique could aid on the histopathological evaluation of melanocytic neoplasms. Sequential cutaneous excisional biopsies of melanocytic lesions and their corresponding ex vivo dermoscopic images were prospectively analyzed. Additional sectioning was executed in areas of dermoscopic concern, having, by reference, a dermoscopic mapping of the sectioned specimens. Diagnostic differences before and after analyzing the new dermoscopy-guided sections were registered. A total of 564 melanocytic lesions were examined, and additional cuts were considered necessary in 84 (14.9%) cases. Of these, 11 lesions (13.1%) had a different final diagnosis after dermoscopy-guided specimen sectioning, including 3 lesions that were reclassified as melanomas and 2 melanomas that were restaged. We found that the combined use of ex vivo dermoscopy and histopathology improves clinical-pathological correlation and allows selection of representative areas for sectioning. Altogether, this technique may improve diagnostic confidence and accuracy in the histopathological evaluation of melanocytic lesions.