Compound Naevus
Author: Dr Olivia Wooler
Chief Editor: Dr Daniel Keith
Compound naevi are benign proliferations of melanocytes in the dermal-epidermal junction and the dermis. They may develop from preexisting junctional naevi, with the dermal proliferation of melanocytes causing the formally flat lesion to become raised.
Macroscopic Appearance
Compound naevi are papules or nodules with variable degrees of pigmentation and elevation. They typically have a raised central area and surrounding flat patch, corresponding to the dermal and junctional components of the lesion, respectively. They may become dome-shaped and feel soft and wobbly to palpate. They are often hairy and can have a smooth or papillomatous (wart-like) surface.
Figure 1.
A smooth compound naevus. The lesion is more raised centrally and flattens at the periphery.
Figure 2.
A hairy compound naevus with a dome shaped central area and a surrounding flat patch.
Figure 3.
Compound naevus with a heavily pigmented, papilloumatous central region and surrounding flat patch.
Image courtesy of Dr Ash Singh, GP.
Figure 5.
Papillomatous compound naevus with numerous hair
Figure 4.
Dome shaped compound naevus with papillomatous surface.
Figure 6.
Smooth compound naevus with regular shape and colour. Similar to lesion 1 the lesion is more raised centrally and flattens in the periphery.
Image courtesy of Dr Ash Singh, GP.
Dermoscopic Appearance
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Pigment patterns - Compound naevi can demonstrate globular, cobblestone, reticular and/or homogenous pigment patterns:
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Globular pattern - this is characterised by well-demarcated round or oval structures distributed throughout the lesion. Globules have a diameter of more than 0.1mm and correspond to junctional nests of melanocytes.
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Cobblestone pattern - this is a variant of the globular pattern in which the globules are larger and more angulated, resembling a cobblestone.
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Reticular pattern - this pattern is defined by a pigment network of intersecting lines resembling a grid. Homogenous pattern - diffuse pigmentation in the absence of a pigment network.
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Homogenous areas include blotches (hyperpigmented, structureless areas), and structureless, hypopigmented areas.
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Benign naevi usually present with one or two (eg. Reticular-globular, reticular-homogenous etc.) of these pigment patterns, in a well-organised and symmetrical manner. Dysplastic naevi and melanoma should be considered in lesions manifesting with a multi-component pattern.
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Vessels - As compound naevi have a dermal component, vascular structures may be seen on dermoscopy. Comma and/or dotted vessels are most commonly observed.
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Hair - Compound naevi are often hairy and it is common to see terminal hairs on dermoscopy. These are often associated with perifollicular hypopigmentation.
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Exophytic papillary structures - These are densely packed, finger-like projections seen in papillomatous naevi.
Figure 7.
Dermoscopic appearance of Figure 1 (annotated left, unannotated right). The lesion has a subtle reticular pattern with dotted and comma vessels throughout. The reticular pattern and vessels can be seen more clearly in the magnified image. Some small roundish areas of hypopigmentation, corresponding to hair follicles can also be seen (arrows).
Figure 8.
Dermoscopic appearance of Figure 2 (annotated left, unannotated right), showing a globular pattern with brown globules and dots. On close inspection, scrutiny vessels can be seen throughout the lesion (circles).
Figure 9.
Dermoscopic appearance of Figure 3 (annotated), revealing a subtle globular pattern with numerous light brown dots and globules throughout. Multiple hairs (arrows), and blood vessels with both comma (asterisks), and dotted (circles) appearances can be seen.
Figure 9. Unannotated
Figure 10.
Dermoscopic appearance of Figure 4 (annotated left, unannotated right), showing a globular pattern. The papillomatous part of the naevus (circle) can be seen in transition with the flat part (arrow). The papillomatous part exhibits several densely aggregated exophytic papillary structures (asterisks). Image courtesy of Dr Ash Singh, GP.
Figure 11.
Dermoscopic appearance of Figure 5 (annotated left, unannotated right). The lesion has a globular pattern with closely packed dots and globules which are various shades of brown. Multiple hairs are present. The are several white-yellow globules representing keratin accumulation (arrows).
Figure 12.
Dermoscopic appearance of Figure 6, showing a cobblestone pattern. Globules are uniform in colour and evenly distributed throughout the lesion.
Image courtesy of Dr Ash Singh.
