Total Body Photography and Sequential Digital Dermoscopy for Melanoma Diagnosis

Abstract

The dermoscopic diagnosis of melanoma is difficult for some early tumors that lack the characteristic features from which a diagnosis is made. The diagnosis of these “featureless melanomas” is facilitated by monitoring over time to document any changes. Monitoring can be done with total body photography (TBP) and, for individual lesions, sequential digital dermoscopy (SDD). TBP allows the detection of both de novo melanomas and melanomas arising in association with a nevus, presenting as a change in a preexisting lesion. TBP helps in the early detection of melanomas in high-risk patients with many nevi, including atypical ones. SDD is useful for monitoring flat, atypical melanocytic lesions lacking clinical or dermoscopic features of melanoma at baseline, allowing the detection of subtle changes. In two prospective studies of high-risk patients, SDD detected 18 of the 53 melanomas or 39% of all melanomas, whereas a retrospective study of routine clinical practice found that the changes observed with SDD allowed the detection of 12 of 99 melanomas. In addition, SDD has been shown to reduce the ratio of benign moles excised for each melanoma diagnosed, thereby reducing the number needed to treat. A combination of TBP and SDD provides optimal surveillance in high-risk patients because melanomas diagnosed this way have been found to be thinner than those detected with standard clinical means. The combination of SDD with reflectance confocal microscopy is useful for the examination of equivocal lesions and lesions that change during monitoring and can help reduce the number of unnecessary excisions.