A red tumor

A 56-year-old woman consulted for a red lesion on her abdomen.

Dermoscopy revealed: regularly distributed hairpin-like vessels in favor of a seborrheic keratosis.

This lesion was excised and pathology confirmed the result.

Seborrheic keratosis is a cause of red tumor. Remind to rule out an amelanotic melanoma which is a great masquerader.

Fast growing tumor

A 65-year-woman consulted for this lesion on her left arm which was present for 3 months.

Dermoscopy revealed peripheral hairpin-like vessels on a whitish area, and a central brownish structureless area.

This lesion was excised and pathology revealed a kératoacanthoma.

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.

Clear cell hidradenoma

Fig 1: clinical picture

A 52-year-old man consulted for a scapular nodule. Clinical examination revealed a flesh-coloured nodule (Fig 1)

Fig 2 dotted vessels

Polarizing dermoscopy with a slight pressure revealed dotted vessels (Fig 2)

Fig 3 whitish areas

Fig 4 whitish areas

Dermoscopy with a louder pressure revealed whitish areas (Fig 3 and 4).

This lesion was excised and pathology revealed a clear cell hidradenoma.

Clear cell hidradenomas are usually benign intradermal tumors and represent 95% of all hidradenomas. These tumors have a slow growth and sometimes can be ulcerated. Theay have to be surgically excised because of a high risk of recurrence and a potential of malignant evolution.

Y. Yoshida and al. reported dermoscopic features of a clear cell hidradenoma (Y. Yoshida and al. Dermatology 2008;217: 250-251).

They found in their case whitish areas, reddish purple areas, and some linear or hairpin vessels on the surface of the tumour. Reddish purple areas were corresponding to cystic spaces with hemorrhage.

Hairpin-like vessels and seborrheic keratoses

These 2 cases of seborrheic keratoses are dysplaying hairpin vessels:

Case 1: clinical view

Case 1: dermoscopic view: numerous hairpin blood vessels 

Case 2: dermoscopic view: rare hairpin vessels

Hairpin vessels can be found in:

• seborrheic keratoses (fine, often surrounded by a hypopigmented halo)
• Melanoma (irregular)
• Spitz nevi
• keratoacanthomas

Keratoacanthoma

This rapidly engrowing lesion for 2 months was clinically in favor of a keratoacanthoma.


In our case dermoscopy revealed:

• an unspecific pattern
• a central ulceration with blood crusts
• a corona of elongated hairpin blood vessels on a white background corresponding to a white keratotic halo
  

Other dermoscopic features of keratoacanthomas are:

• multicomponent pattern
• polymorphous vessels
• central keratotic plug
  

Elongated hairpin blood vessels on a white keratotic halo are non specific of keratoacanthomas and can be observed in invasive squamous cell carcinomas.

Keratoacanthomas is considered as "benign" variant of squamous cell carcinoma. The first line therapy consists in an excision although other alternatives are possible (imiquimod, PDT, etc...)

Other cases: 1

Hairpin blood vessels

A 52-year-old man consulted for this inguinal exophytic pigmented tumour.


Dermoscopy revealed fissures and ridges (black rectangle) and a vascular pattern with many hairpin blood vessels (red rectangle).

Pictures taken with Fotofinder dermoscope

Hairpin blood vessels and fissures and ridges were in favor of a seborrheic keratosis.

Hairpin blood vessels are quite typical of seborrheic keratoses (particularly if there is a white halo surrounding them) but are non specific and can be found also in:

• melanocytic nevi
• keratoacanthomas
• basal cell carcinomas
• melanomas (often thick and irregular)
  

Seborrheic keratosis (keratotic subtype)

A 72-year-old man was referred for this scaly lesion on his scalp.

Clinical and dermoscopic evaluation were in favor of a keratotic type of seborrheic keratosis.


Dermoscopy revealed:

• an unspecific pattern (white to yellow horn masses over a background brown coloration)
  
• peripheral hairpin vessels
  

Seborrheic keratoses in most cases are clinically and dermoscopically diagnosed.

Main dermoscopic signs are:

• milia-like cysts
• comedo-like openings (crypts, pseudo follicular openings)
• fissures and ridges ("brain-like" or cerebration's appearance)
• fingerprint-like structures
• moth-eaten border
• hairpin blood vessels
• network-like structures
• sharp demarcation
• fat fingers
  

In the keratotic subtype of seborrheic keratosis an unspecific pattern is frequently observed and, because of the exaggerated ortho-hyperkeratosis, local features are not visible.
In our case, dermoscopic examination reveals hairpin blood vessels which is a typical local sign of seborrheic keratosis.

Keratoacanthoma

A 72-year-old man consulted for a rapidly enlarging tumor on his right forearm. The lesion appeared 3 to 4 months before.


The main clinical diagnosis was a keratoacanthoma.

Dermoscopy revealed:

• a central brownish structureless area corresponding to a central mass of keratin
• a whitish area with presence of elongated hairpin vessels
  

A central brownish structureless area (black circle) and hairpin vessels on a whitish background (white circle) are the two main dermoscopic signs in favor of a keratoacanthoma.

The diagnosis was confirmed by pathology after the complete excision of the tumor.

Basal cell carcinoma

Clinical picture
A 44-year-old woman consulted for this lesion on her back with a circinar papulous border clinically suspicious of being a basal cell carcinoma.


Dermoscopy 1
In dermoscopy the lesion lacked pigment network.
There were blue- gray globules and polymorphous vessels (glomerular vessels, linear irregular vessels, hairpin vessels)

Dermoscopy 2


Dermoscopy 3
Glomerular vessel and hairpin vessels (right part)


Dermoscopy 4
irregular linear vessels

In this case, vascular pattern was atypical for a basal cell carcinoma which features typically arborizing tree vessels. Irregular linear vessels are more often observed in melanomas.
The lesion was excised and pathology confirmed the diagnosis of basal cell carcinoma.

Other cases of basal cell carcinomas: 

1 2 3 4 5 6 7 8 9  10 11 12 13 14 15 16 17 18 19 20 21

Hairpin blood vessels

A 67-year-old woman presented this small dome shaped tumor of her neck.
Dermoscopy revealed many hairpin blood vessels at the periphery in favor of a seborrheic keratosis.

Hairpin blood vessels are frequently seen in seborrheic keratoses. They can have a white halo surrounding them. They can also be observed in melanocytic nevi, keratoacanthomas, basal cell carcinomas, and in melanomas, but in this late case are thicker and more irregular. The dermoscope has to be applied slightly on the lesion to take good images.

Hairpin vessels

A 67-year-old man presented a pruritic lesion on his right leg. The main clinical diagnosis was a seborrheic keratosis.
Dermoscopy revealed numerous hairpin vessels (red circle) and hyperkeratinized areas (black circle) confirming the diagnosis of seborrheic keratosis.

Dermatofibroma

This woman presented a dermatofibroma on her lower right leg confirmed by a biopsy.
The dermoscopy showed a vascular pattern (*) with a rim of hairpin vessels.
The central white patch was less remarkable than in other cases of dermatofibromas.
Dotted vascular pattern or atypical vascular pattern in dermatofibromas have been reported in the literature (Ferrari et al , Acta Derm Venereol 2004, 84: 164-165)

Atypical dermatofibroma with vascular pattern

A 68-year-old man consulted for this lesion on his right leg present for more than 15 years.
Dermoscopy revealed some light brown globules (*) and a vascular pattern with polymorphous vessels: hairpin vessels, dotted vessels, and linear-irregular vessels.
A biopsy was performed and revealed a dermatofibroma.
Dermatofibromas with vascular pattern have been reported in the literature (D.Picolo, K.Peris, page 287, in color atlas of melanocytic lesions of the skin, Springer edition, 2007)