Characterization of 1152 lesions excised over 10 years using total-body photography and digital dermatoscopy in the surveillance of patients at high risk for melanoma.

BACKGROUND

The combined use of total-body photography and digital dermatoscopy, named "two-step method of digital follow-up," allowed the detection of incipient melanoma as a result of dermatoscopic or macroscopic changes during follow-up.

OBJECTIVE

We sought to assess dermatoscopic features and dynamic changes leading to excision of melanocytic lesions during our 10-year experience of monitoring patients at high risk for melanoma.

METHODS

We analyzed 1152 lesions excised during the surveillance of 618 patients at high risk for melanoma from 1999 to 2008.

RESULTS

A total of 779 excised lesions had been previously recorded: 728 were removed because of dermatoscopic changes during follow-up and 51 were removed even though no significant change was noted. The remaining 373 excised lesions were new or undetected on previous total-body photography. A total of 98 melanomas were detected, 60 in the monitored lesions, and 38 among the "new" lesions. The most frequent dermatoscopic changes detected were asymmetric enlargement in almost 60% (n = 418), focal changes in structure in 197 (27%) and in pigmentation in 122 (17%), the latter two being more frequently seen in melanomas than in nevi (both P < .001). No significant differences were detected between dermatoscopic or histopathological characteristics of the melanomas in each group, with a considerable proportion of melanomas misclassified as benign in both groups (26.3% and 38.3%, respectively).

LIMITATIONS: The dermatoscopy pattern of stable lesions and the histopathology of lesions not removed were not included in the study.

CONCLUSION

The most frequent dermatoscopic features associated with melanoma were focal change in pigmentation or structure. Melanomas detected by dermatoscopic changes were remarkably similar to those detected in total-body photography. Almost 40% of melanomas diagnosed in individuals at high risk corresponded to lesions that were not under dermatoscopic surveillance.