Age- and site-specific variation in the dermoscopic patterns of congenital melanocytic nevi: an aid to accurate classification and assessment of melanocytic nevi.
OBJECTIVE
To describe the dermoscopic features of congenital melanocytic nevi (CMN) and assess whether predominant dermoscopic patterns present in CMN are related to an individual's age (<12 years vs >or=12 years), sex, or lesional site (head, neck, and trunk vs extremities).


METHODS
Nonrandomized observational study.


METHODS
A total of 77 consecutive patients, each with 1 CMN (n = 77 lesions), from an outpatient dermatology clinic. A diagnosis of CMN was established by (1) documentation of a melanocytic nevus during the first year of life or (2) by clinical examination and either clinical history or biopsy findings.


METHODS
Images of CMN were evaluated for specific dermoscopic structures and patterns. The distribution of patterns was assessed by age, sex, and lesional site.


RESULTS
Most of the 77 lesions exhibited 1 of the following predominant dermoscopic patterns: reticular (18 lesions [23%]), globular (14 [18%]), or reticuloglobular (12 [16%]). Globular CMN were present in 5 of the 19 individuals who were younger than 12 years (26%) but in only 9 of the 58 individuals 12 years or older (16%). Reticular CMN were seen exclusively in the individuals who were 12 years or older. Congenital melanocytic nevi exhibiting no predominant pattern were more commonly present in the individuals younger than 12 years. Globular CMN were present in 11 head, neck, and trunk lesions (30%) compared with 3 extremity lesions (8%). Conversely, reticular CMN were present in 16 extremity lesions (40%) compared with 2 head, neck, and trunk lesions (5%). The predominant dermoscopic pattern did not vary based on sex. The most commonly observed dermoscopic structures were globules (in 64 lesions [83%]), hypertrichosis (in 61 [79%]), and reticular networks (in 55 [71%]).


CONCLUSIONS
Our results suggest that the predominant dermoscopic patterns of CMN vary according to age and lesional site. These differences may inform future studies on the pathogenesis of CMN.
Changchien
Lily
L
Dermatology Service, Department of Medicine, Memorial Sloan-Kettering Cancer Center, 160 E 53rd St, Second Floor, New York, NY 10022, USA.
Dusza
Stephen W
SW
Agero
Anna Liza Chan
AL
Korzenko
Adam J
AJ
Braun
Ralph P
RP
Sachs
Dana
D
Usman
M Haris U
MH
Halpern
Allan C
AC
Marghoob
Ashfaq A
AA
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002648:Child; D002675:Child, Preschool; D046169:Dermoscopy; D005121:Extremities; D005260:Female; D006258:Head and Neck Neoplasms / Q000151:congenital* / Q000473:pathology*; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009508:Nevus, Pigmented / Q000151:congenital* / Q000473:pathology*; D012737:Sex Factors; D012878:Skin Neoplasms / Q000151:congenital* / Q000473:pathology*; D013909:Thorax