Module 5: Melanocytic Nevi Flashcards
New classification of nevi based on Dermoscopy
cobblestone pattern globular p reticular p homogenous blue p starburst p not specific p
New classification - pigment distribution
Uniformly pigmented Central hyper pigmented central hypo pigmented eccentric hyper pigmented eccentric hypopigmented multifocal hyper/ hypo pigmented
New classification - color
Light brown Dark brown Red White Blue Black Grey
2 main categories of melanocytic nevi
Congenital
Acquired
Categories of congenital nevi
Large
Medium
Small
Categories of acquired nevi
Junctional, compound, dermal
Spitz
Blue
Other
Incidence of congenital nevi
Likely 1% or lower
Risk of melanoma in CN?
Small - medium 0-5% lifetime risk
Giant 5-15%
Origin of melanoma in CN
Dermis
Congenital nevis, dermoscopic features
- Asymmetry
- Pattern
a. Multicomponent
b. Globular (cobblestone)
c. reticular
d. Homogenous - Pigmentation
a. Uniform
b. Hypo/ hyper-pigmented
Congenital nevis, additional dermoscopic features
Hypertrichosis
Perifollicular hyper/ hypo-pigmentation
Vessels
Definition giant congenital nevus
> 20 cm adult
6 cm birth
9 cm birth, head
Management giant congenital nevus
- MRI to r/o neurocutaneous melanosis
- Early surgery if appropriate
- Follow up examination every 6 months.
Management small/ medium congenital nevi
If suspicious features excise If change in lesion excise if difficulty with documentation excise If unable to do full excision do partial excision of suspicious area. If unable to excise follow up.
What is histopathological correlate of globular pattern?
Nests of melanocytes at the Dermoscopy-epidermal junction and dermis
