Recognition of early melanoma: a monocentric dermoscopy follow-up study comparing de novo melanoma with nevus-associated melanoma.

BACKGROUND

The earlier detection of melanomas occurring within preexisting nevi is theoretically possible using sequential dermoscopy. Characterizing the early follow-up changes of nevus-associated melanomas (NAMs) and differentiating them from those observed in de novo melanomas (DNMs) may help the earlier recognition of NAMs.

METHODS

Using descriptive dermoscopic features to detect focal changes, we blindly evaluated retrospectively the baseline and follow-up images of 32 melanomas that were subsequently classified as histopathologically defined NAMs or DNMs.

RESULTS

Correlates of growth, as structureless brown‐black areas or clods, complemented each other for the identification of DNMs at baseline (structureless brown‐black areas: 66.7% DNMs, 15% NAMs, P < 0.01; combined with clods, one or the other being present: 100% DNMs, 30% NAMs, P < 0.01) and when considering their baseline presence or their appearance at follow‐up (100% DNMs, 35% NAMs, P < 0.01). Correlates of fibrosis, as white lines, when considering their baseline presence or their appearance at follow-up, were associated with NAMs (60%, 16.7% DNMs, P = 0.027).

CONCLUSION

Significant differences, distinguishing NAMs from DNMs, were detected particularly when considering both baseline signs and follow-up changes. Earlier identification of NAMs and their subsequent improved histological characterization will help define the subgroup of high-risk patients, for whom comprehensive image monitoring may be beneficial.