Sensitivity and specificity of ex vivo dermatoscopy: a case series

Sensitivity and specificity of ex vivo dermatoscopy (EVD) for malignancy detection of skin tumors is unknown. We sought to assess whether the use of EVD could be a useful adjunct to histopathological diagnosis of pigmented skin tumors, including cases where complete clinical information is inadequate or missing.

EVD was performed on 195 excised, formalin-fixed pigmented skin tumors.

Of 183 eligible lesions, 104 (56.8%) were melanocytic and 79 (43.2%) nonmelanocytic. Overall, 54 (29.5%) were malignant: 10 melanomas, 39 basal cell carcinomas, and five squamous cell carcinomas. Ex vivo images were devoid of red color. The following colors were seen: light and dark brown, grey, blue, black, and white. All structures typical for pigmented melanocytic and nonmelanocytic lesions were observed. In malignant nonmelanocytic lesions, diagnostic accuracy and sensitivity for malignant/benign decision was not better when combining visual assessment and EVD but diagnostic specificity improved by 3.0%. For melanoma, combined diagnostics improved diagnostic accuracy, sensitivity, and specificity for 9.6, 30.0, and 7.5%, respectively.

For dermatopathologists, EVD offers increased specificity for all categories of tumors and increased diagnostic accuracy, sensitivity, and specificity for melanoma. With EVD view, the dermatopathologist can instantly find areas of interest, thus minimizing the possibility for missing a malignant lesion.