Morphologic features and natural history of scalp nevi in children

To characterize the clinical changes in clinically distinctive scalp nevi over time in children to help guide management and avoid misdiagnosis as melanoma.

Cohort study.

Washington University School of Medicine pediatric dermatology clinics. Patients Of 93 patients younger than 18 years with photographically documented, clinically distinctive scalp nevi, 28 (30%) consented to participate. Minimum follow-up from the initial visit was 1 year. Collectively, these patients had 44 scalp nevi at the initial visit. No patient had a personal diagnosis of melanoma or dysplastic nevus syndrome.

Clinical changes in scalp nevi as determined using the ABCDE scoring system (ie, asymmetry, border irregularity, color variegation, diameter >6 mm, and evolution/elevation from initial to follow-up images) on initial and follow-up photographs of scalp nevi.

Overall, 77% of the clinically distinctive scalp nevi (34 of 44) showed clinical signs of change during mean follow-up of 2.8 years. Of those with changes, 18 (53%) became more atypical and 16 (47%) became less atypical since the initial examination. None of the changes were concerning for melanoma. The mean total scalp nevus count was 2.6. Scalp nevi represented approximately 6% of total-body nevi. The number of scalp nevi increased with age. Boys had 1.5 times the number of scalp nevi as girls (P = .03).

Scalp nevi are clinically dynamic in childhood. These changes include an increase or a decrease in atypical features and occur in all age groups. This preliminary study does not support excisional biopsies but does support physician evaluation of scalp nevi evolution and serial photography of clinically distinctive lesions.