nevus spilus (NS) or speckled lentiginous nevus (SLN) typically presents before the age of 2 as a light brown macule or patch containing smaller, more darkly pigmented macules or papules within the borders (

Figure 1. A clinical image of a nevus spilus. ). These smaller pigmented aspects may appear after the first background patch is noted. NS is thought by most but not all authors to represent a type of congenital melanocytic nevus. Typically a NS is a benign, isolated lesion with limited dimensions. The larger background patch tends to range in size from 2 to 10 cm, though it can reach the size of greater than 20 cm, as seen in giant congenital nevi. The smaller pigmented "speckles" tend to range in size from 1 to 3 mm, and can reach up to 9 mm in diameter.

Microscopically, the two types of clinical features appear very different. The tan-brown background pigmentation exhibits features with lentigo simplex: the epidermis is acanthotic with elongation and hyperpigmentation of the rete ridges and an associated mild increase in the number of single melanocytes along the dermal-epidermal junction. Others have reported the appearance of melanocytic nests in these areas as well.

In contrast, the “speckled areas” within this lentiginous background can exhibit a range of reported histolopathologic appearances: from simple lentigines to ordinary nevi (junctional, compound or intradermal) to blue nevi to Spitz nevi. There have been reported cases of melanoma arising in nevus spilus. Schaffer has likened the speckled lentiginous nevus/nevus spilus to a “…melanocytic garden, and within this garden a variety of lesions can grow, from junctional nevi to blue nevi to melanoma…” No consistent correlation has been made between the clinical setting of the nevus spilus, the anatomic distribution or their histopathologic