- Introduction to dermatoscopy CME
- Dermatoscopic features CME
- Three-point checklist CME
- Dermoscopy of benign melanocytic lesions CME
- Dermoscopy of atypical naevi CME
- Dermoscopy of malignant melanoma CME
- Dermatoscopy of seborrhoeic keratosis CME
- Dermoscopy of basal cell carcinoma CME
- Dermatoscopy of squamous cell carcinoma CME
- Dermatoscopy of other non-melanocytic lesions
- First step algorithm CME
- Pattern analysis CME
- Other algorithms for melanocytic lesions CME
- The dermatoscopy report CME
- Melanocytic naevi: new classification CME
- Dermoscopy of the nail CME
- Dermatoscopic-histologic correlation CME
- Blue naevus images CME
- Globular (congenital) naevus images CME
- Reticular (acquired) naevus images CME
Developed in collaboration with the University of Auckland Goodfellow Unit in 2007.
Author: Hon A/Prof Amanda Oakley, Dermatologist, Hamilton, New Zealand, 2008.
Images have been sourced from the following:
- Hon Assoc Prof Amanda Oakley
- The Department of Dermatology, Waikato Hospital
- MoleMap New Zealand (with permission)
- Dr Richard Williamson and coworkers (as indicated in dermatoscopic-histology page*)
Melanocytic naevi: new classification CMENext Previous
Why have a new classification?
The conventional system has divided melanocytic naevi according to history (congenital or acquired) and histopathology (junctional, compound and dermal location of melanocytes). However clinical diagnosis is often imprecise. Historically, naevi were thought to start as junctional melanocytic nests, and progress to become compound then dermal in time. Careful dermoscopic observation of numerous naevi has shown this theory to be implausible.
Dermoscopy often allows precise diagnosis of different types of melanocytic naevi based on the amount and distribution of pigmentation. Often an individual has many benign naevi that look similar to one another, allowing the ugly duckling that looks different from the others to be recognised as a melanoma.
The new classification has seven groups. Clinicians may wish to use it when describing dermoscopic features of melanocytic naevi.
Globular (congenital) naevus
The globular naevus is characterised dermoscopically by a globular pattern. These lesions are present at birth or arise in childhood, and are likely to be constitutionally predetermined. They persist lifelong.
|Age||Clinical features||Dermoscopic features||Histopathology|
|Childhood||Small: brown, flat, symmetrical, <15 mm.||
|Large: flat to elevated with verrucous/hairy surface, >15 mm. True congenital naevi.||
Reticular (acquired) naevus
The reticular naevus is characterised dermoscopically by a reticular or network pattern of pigmentation. They arise during childhood and adult life, most likely triggered by sun exposure or other factors. They have a tendency to regress in later life and may disappear.
|Size||Clinical features||Dermoscopic features||Histopathology|
Starburst (Spitz/Reed) naevus
The starburst (Spitz/Reed) naevus has two distinct dermoscopic patterns. These lesions are uncommon, and may arise in children or young adults. Changing lesions may be difficult to distinguish from melanoma, and should be excised.
|Type||Clinical features||Dermoscopic features||Histopathology|
Blue (homogeneous) naevus
The blue naevus is dermoscopically characterised by homogenous steel blue colour. Blue naevi may be congenital or acquired and are persistent.
|Clinical features||Dermoscopic features||Histopathology|
|Flat to elevated, blue to black||
Naevi on palms and soles/nails, and naevi on the face, genitals and nipples have particular dermoscopic features.
|Site||Clinical features||Dermoscopic features||Histopathology|
|Lips||Congenital or prepubertal|
|Nipple||Congenital or prepubertal|
Naevi with special features
This group includes:
- Combined naevi (two types of naevi juxtaposed or merged)
- Halo naevi (uniform lymphocytic reaction)
- Irritated naevi (patchy lymphocytic reaction)
- Cockade naevus
- Naevi with eczematous halo (Meyerson type)
- Recurrent naevi following surgery
|Type||Clinical features||Dermoscopic features|
|Naevi with eczematous halo (Meyerson type)||
Unclassifiable melanocytic lesions
This category comprises atypical or non-diagnostic lesions, which are often clinically or dermoscopically suspicious of melanoma but are not malignant on histology. They may be superficial or nodular.
Classify the next fifty naevi you examine.