The Natural Evolution of a Pigmented Spitz-Reed Nevus in a 24 Months Dermoscopic Follow Up

The natural evolution of Spitz-Reed nevi is poorly understood, owing to the lack of studies investigating their longterm clinical evolution and the fact that most of the lesions are surgically excised. The surgical approach is indicated because of the clinical and histopathologic similarities with melanoma that may create diagnostic confusion in some cases. Hence nowadays, due to the low incidence of melanoma in children and the development of diagnostic dermoscopic criteria, a less aggressive approach to SRN may be reserved, especially in cases with typical features. We report a case of a pigmented lesion that showed gradual changes, from a Spitz Reed Nevus with typical clinical and dermoscopic features, to a common nevus.

The natural evolution of Spitz-Reed nevi (SRN) is poorly understood, owing to the lack of studies investigating their long-term clinical evolution and the fact that most of the lesions are surgically excised [1,2].
The surgical approach is indicated because of the clinical and histopathologic similarities with melanoma that may create diagnostic confusion in some cases.
Hence nowadays, due to the low incidence of melanoma in children and the development of diagnostic dermoscopic criteria, a less aggressive approach to SRN may be reserved, especially in cases with typical features [3,4].
We report herein a case of a pigmented lesion that showed gradual changes, from a Spitz Reed Nevus (SRN), with typical clinical and dermoscopic features, to a common nevus.

Report of a Case
A 6-year-old boy was referred by his pediatrician with a 4-mm, black, symmetric macule located on the right arm. Dermoscopically, the lesion exhibited a starburst pattern characterized by a rim of pigmented streaks at the periphery ( Figure 1A). Because of the typical dermoscopic pattern suggestive of SRN, no biopsy was performed, and the boy was scheduled for a follow-up visit at six months, as suggested by other authors [1]. After 6 and 12 months ( Figure 1B and 1C), the streaks were not discernible any more, and only remnants of lightbrown to gray pigmentation were still visible. At 24 months' time the lesion exhibited almost complete loss of the dermoscopic features of SRN, presenting only delicate remnants of light brown pigmentation as the only visible feature ( Figure 1D).  Figure 1A); streaks not discernible any more ( Figure  1B); then, remnants of light-brown to gray pigmentation still visible ( Figure 1C); at 24 months' time, almost complete loss of dermoscopic features of Spitz-Reed nevus presenting only delicate remnants of light brown pigmentation ( Figure 1D). prior to dermoscopy. The increasing confidence of the clinicians with this non-invasive technique and the development of morphologic criteria for the diagnosis of pigmented lesions, nowadays, enables trained clinicians to identify peculiar characteristics of these lesions in order to prevent unusual excisions when possible [4,5]. In pediatric population a surgical excision may have to deal with general anesthesia and collateral effects. Most of the parents would not be happy to deal with such decisions. The incidence of melanoma in a pediatric population is extremely rare [3] and when dealing with lesions that present typical characteristic features of SRN, literature data suggest that a non-aggressive approach is now well accepted. Other authors as a matter of fact, already published their data on the natural evolution of SRN [6,7]. They emphasize the fact that the involution of SRN might be the reason why the incidence of these lesions in adults seems to be much lower than in children. Hence, precise clinical and dermoscopic criteria of SRN that go through an involution process have not been described in large series, especially in children in order to evaluate the percentage of lesions that involve, in order to make such an assumption.
Their reports together with this case we presented, strongly suggest the hypothesis that lager study on clinical evolution of SRN should be performed, in order to establish a standardized approach.