2 colors, 1 diagnosis

A 45-year-old woman was referred for this pigmented lesion with 2 colors.

Diagnosis was easy with dermoscopy:

• comedo-like openings 
• milia-like cysts
• fissures and ridges 
• network-like structures
• sharp demarcation

in favor of a seborrheic keratosis

Lost among black benign lesions....

A 72-year-old patient consulted for many pigmented lesions on his back. Most of them were seborrheic keratoses...........

............except this one.

Dermoscopy revealed:

• a multi- colored pattern
• a sharp demarcation
• an atypical reticular network
• a blue white veil

This lesion was excised and pathology revealed a superficial spreading melanoma (Breslow index 0.72mm) developed on a melanocytic nevus

Cervical lesion.

A 62-year-old woman consulted for this cervical lesion which was present for 10 months.

Dermoscopy revealed sharp demarcations, scales and some hairpin-like vessels.

The lesion was excised and pathology revealed a seborrheic keratosis.

The main clue was the presence of hairpin-like vessels.

Seborrheic keratosis

A 50-year-old woman consulted for an enlarging and pruritic lesion on her back.

This pigmented lesion was characterized in dermoscopy by:

• absence of pigment network
• sharp demarcation
• presence of milia-like cysts
• comedo-like openings

This dermoscopic presentation was typical of a seborrheic keratosis.

Superficial spreading melanoma

A 66-year-old man consulted for a pigmented lesion on his left scapular area.

Dermoscopy revealed a multi-component pattern, asymmetry, and multiple colours (tan, dark brown, black, blue gray, white).
Other signs were an atypical reticular pattern (irregular holes and thick lines) with a sharp demarcation, a blue-white veil and atypical vessels (irregular linear vessels), a central ulceration (crust). Dots were irregularly distributed.

All these dermoscopic signs were in favor of a superficial spreading melanoma.

Seborrheic keratosis

A 47-year-old woman consulted for this dark pigmented lesion on her neck.


Dermoscopy featured comedo-like openings (yellow arrows) and crypts (red arrow). There was no pigment network and the lesion was sharp demarcated.
These different criteria were in favor of a seborrheic keratosis.


It is important to remind that no single criterion by itself is diagnostic and an accurate and complete examination of the different dermoscopic features is necessary before diagnosing a seborrheic keratosis.

Milia-like cysts

This patient presented an enlarging pigmented lesion on her back for 2 years.


Dermoscopy: lack of pigmented network, sharp borders, comedo-like openings and many milia-like cysts were in favor of a a seborrheic keratosis.


Many milia-like cysts like stars in the sky are typically found in seborrheic keratoses.

Milia-like cysts and comedo-like openings

A 74-year-old man consulted for a pruritic pigmented lesion on his back.


Dermoscopy was in favor of a seborrheic keratosis: pigmentation with sharp demarcation, milia-like cysts and comedo-like openings.


Milia-like cysts are white or yellow, round bodies, frequently observed in seborrheic keratoses. They can be seen in compound or dermal nevi, melanomas, pigmented basal cell carcinomas but are usually solitary or in a small number.


Comedo-like openings are pigmented and ovale yellowish, brown or black structures. They can also be observed in melanocytic lesions and melanomas.

Acanthotic seborrheic keratosis

A 76-year-old woman presented a seborrheic keratosis on her back.
It was an acanthotic type.
In dermoscopy, the lesion presented a sharp demarcation, a dark-brown background coloration on the left part of the lesion , numerous milia-like cysts (black circle), comedo-like openings (blue lines), and crypts (red circle)

Solar lentigo

A 72-year-old man consulted for a slowly enlarging pigmented lesion on the dorsal side of his right hand.

clinical view

dermoscopy x 20

Sharply demarcated border and finger-print like structures in favor of a solar lentigo or a flat seborrheic keratosis.

A biopsy confirmed the diagnosis of solar lentigo.










dermoscopy x50