Clinical and dermoscopic features of 88 scalp naevi in 39 children

Paediatric scalp naevi may represent a source of anxiety for practitioners and parents, as the clinical and dermoscopic features of typical naevi have yet to be defined. Prompted by concern about the large size, irregular borders and colour variation of scalp naevi, clinicians and parents may request unnecessary excision of these naevi.

To establish the typical clinical and dermoscopic patterns of scalp naevi in children younger than 18 years old to help optimize clinical care and management.

Scalp naevi were imaged with a camera (Canon Rebel, XSi; Canon, Tokyo, Japan) and dermoscopic attachment (Dermlite Foto, 30 mm lens; 3Gen, San Juan Capistrano, CA, U.S.A.) to the camera. The clinical and dermoscopic images were reviewed and analysed. Both acquired and congenital scalp naevi were included but were not further differentiated from each other.

We obtained clinical and dermoscopic images of 88 scalp naevi in 39 white children. Two subjects had received chronic immunosuppressive medication. Nineteen children had a family history of melanoma. Boys (18/39 subjects, 46%) possessed 68% (60 naevi) of scalp naevi imaged. Younger (< 10 years old) subjects (24/39 subjects, 62%) possessed 42% (37 naevi) of scalp naevi. The main clinical patterns included eclipse (n=18), cockade (n = 3), solid brown (n=42) and solid pink (n=25) naevi. Solid-coloured naevi showed the following dermoscopic patterns: globular (57%), complex (reticular-globular) (27%), reticular (9%), homogeneous (6%) and fibrillar (1%). The majority of naevi had a unifying feature - perifollicular hypopigmentation, which caused the appearance of scalloped, irregular borders if occurring on the periphery, or variegation in pigmentation, if occurring within the naevi.

Older subjects and boys tend to harbour a larger proportion of scalp naevi. The main clinical patterns include solid-coloured and eclipse naevi. The most common dermoscopic pattern of scalp naevi is the globular pattern. Perifollicular hypopigmentation is a hallmark feature of signature scalp naevi. Dermoscopy is a noninvasive tool in the evaluation of cutaneous melanocytic lesions in children and may decrease the number of unnecessary excisions.