Diagnosis and categorization of acral melanocytic lesions using teledermoscopy.

We performed a multicentre study to test the validity of teledermoscopy for diagnosing acral melanoma and to evaluate inter-observer agreement on the classification of acral melanocytic lesions. Dermoscopic images of 77 acral melanocytic lesions (71 common melanocytic naevi and 6 melanomas) were sent by email to 11 dermatologists with different degrees of experience in dermoscopy. The observers analysed the images on a computer monitor to diagnose acral melanoma or atypical lesions and to categorize all lesions. All 11 observers, regardless of their degree of experience, obtained high values for sensitivity (mean 0.91, SD 0.09) and specificity (mean 0.95, SD 0.04) with regard to the diagnosis of melanoma. The inter-observer agreement was good to excellent (kappa 0.49-0.88) for the categorization of acral melanocytic lesions. All six melanomas were correctly classified as 'atypical pattern' and all observers recommended surgical excision. Teledermoscopy represents a useful tool for the diagnosis of acral melanoma and for the categorization of patterns that suggest benign or potentially malignant acral melanocytic lesions.