"Compound blue nevus": a reappraisal of "superficial blue nevus with prominent intraepidermal dendritic melanocytes" with emphasis on dermoscopic and histopathologic features.
We describe 5 cases of "compound blue nevus" (CBN) ("superficial blue nevus with prominent intraepidermal dendritic melanocytes," "Kamino nevus"). Dermoscopically in 2 of 4 cases the bluish pigmentation characteristic of blue nevi was centrally replaced by a black lamella, with black dots and brown globules also observed in one case, thus revealing a structural asymmetry suggestive of melanoma. Histopathologically, pigmented parakeratosis was the underlying histopathologic finding of black lamella and dots/globules. Immunohistochemistry highlighted the unique histopathologic feature of CBN, namely, single dendritic melanocytes at the dermoepidermal junction with striking intraepidermal prolongations. Our findings confirm that CBN is a distinctive variant of blue nevus that may mimic cutaneous melanoma both clinically and dermoscopically.
Ferrara
Gerardo
G
Pathologic Anatomy Service, Gaetano Rummo General Hospital, Benevento, Italy.
Argenziano
Giuseppe
G
Zgavec
Borut
B
Bartenjev
Igor
I
Staibano
Stefania
S
De Rosa
Gaetano
G
Soyer
H Peter
HP
D000293:Adolescent; D000328:Adult; D001132:Arm; D002648:Child; D003713:Dendritic Cells / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008544:Melanocytes / Q000473:pathology; D008545:Melanoma / Q000473:pathology*; D008853:Microscopy; D009333:Neck; D018329:Nevus, Blue / Q000473:pathology*; D012878:Skin Neoplasms / Q000473:pathology*; D013909:Thorax