Dermoscopic changes in melanocytic nevi covered with both an opaque tape and sunscreen cream during narrowband ultraviolet B therapy

Background: Ultraviolet (UV) light may cause dermoscopic changes on melanocytic nevi (MN). Objectives: To investigate the effects of sunscreen (SSc) application on dermoscopic changes in MN during narrow band UVB (NBUVB) therapy. Methods: Half of the randomly selected MN in each patient were covered with opaque tape and SSc [SSc(+)], and the rest were covered with only opaque tape [SSc(-)] during NBUVB treatment sessions. Results: A larger proportion SSc(-) MN displayed dermoscopic changes at end of NBUVB therapy compared to the start of therapy (p=0,035). The number of the MN that decreased in size and showed loss of structure was significantly higher in SSc(-) MN (p=0.04 and p=0.026, respectively). Conclusions: Sunscreen in combination with opaque tape may contribute to some dermoscopic changes in melanocytic nevi, including decrease in size and loss of structure.