Les kératoses séborrhéiques – Table des matières (pour les professionnels)

Table of Contents (For Professionals) Seborrheic keratosis=SK Introduction -Historical Features -Epidemiology Clinical Features -Clinical Presentation -Differential diagnosis on clinical grounds Dermatoscopical Features -Differential Diagnosis on dermoscopical grounds Histological Features Association of SK with systemic disease Etiology -Origin of SK follicular epithelium solar lentigo -Causal factors Uv exposure HPV infection (Human papillomavirus)) deficiency in presenilin vitamin…

Les kératoses séborrhéiques (verrues séborréiques)(verrues séniles)(taches de vieillesse)

Caractéristiques cliniques (pour les professionnels)

Clinical Features (For Professionals) Dr Christophe HSU – dermatologist. Geneva, Switzerland Clinical Presentation Usually, the diagnosis is straightforward. Histology is needed in doubtful cases. {Pierson, 2003}SKs have many ways of presenting, they can appear as macules, papules or plaques which are normally sharply demarcated from the surrounding normal skin.  They are generally brown in colour…

Les kératoses séborrhéiques (verrues séborréiques)(verrues séniles)(taches de vieillesse)

Caractéristiques dermatoscopiques (dermoscopiques) (pour les professionnels)

Seborrheic Keratosis = SK Cerebriform like appearance and milia-like cysts Dermoscopical Features (dermatoscopy) (For Professionals) – Hairpin vessels are long capillary rings which develop at the periphery of keratinising tumours {Kreusch, 1996}. Typically, many vessels bunch together and are surrounded with a white halo, thus giving a grape-like appearance {Braun, 2002}. This characteristic is more…

Les kératoses séborrhéiques (verrues séborréiques)(verrues séniles)(taches de vieillesse)

Caractéristiques histologiques (Histologie)(pour les professionnels)

Histological Features (Histology) (For professionals) Seborrhoeic keratosis=SK In case of diagnostic doubt, a shave biopsy ought to be done. SK are benign epithelial tumours which are part of the group of acanthomas {Brownstein, 1985}. SK is postulated to be of follicular keratinocytic origin {Mehregan, 1964; Degos, 1968}, and can show an exophytic (upwards)  sometimes endophytic…

Les kératoses séborrhéiques (verrues séborréiques)(verrues séniles)(taches de vieillesse)

Association avec des maladies internes (pour les professionnels)

Association with Internal Diseases (For Professionals) The rapid apparition of SK mostly when it is associated with acanthosis nigricans (35% of patients) and especially pruritus{Holdiness, 1988} should raise the suspicion about an internal malignancy. There is a big polemic about the existence of this rare sign called Leser-Trélat. The information concerning this sign is shown…

Les kératoses séborrhéiques (verrues séborréiques)(verrues séniles)(taches de vieillesse)

Etiologie (pour les professionnels) (en anglais)

Etiology (For Professionals) The origin and cause of SK is to the best of our knowledge unknown and what follows below is a list of proposed hypotheses. Origin of SK Hair follicle epithelium Whatever, the triggers and mechanisms of pathogenesis of seborrheic keratosis, they seem to develop from the follicular epithelium.This hypothesis come from the…

Les kératoses séborrhéiques (verrues séborréiques)(verrues séniles)(taches de vieillesse)

Mécanismes de croissance (proposés)(pour les professionnels)

Mechanisms of Growth (Hypothesis) (For Professionals) Two schools of thought exist, one states that SK develops from an accumulation of senescent cells, whereas the other states that cells hyperproliferate. Ki-67 is a marker of proliferation that links itself to the Dense Fibrillary Component of the nucleolus (reference). We used ki-67 marking of SK to try…

Les kératoses séborrhéiques (verrues séborréiques)(verrues séniles)(taches de vieillesse)

Mécanismes de croissance (proposés)(pour les professionnels)

Mechanisms of Growth (Hypothesis) (For Professionals) Two schools of thought exist, one states that SK develops from an accumulation of senescent cells, whereas the other states that cells hyperproliferate. Ki-67 is a marker of proliferation that links itself to the Dense Fibrillary Component of the nucleolus (reference). We used ki-67 marking of SK to try…

Les kératoses séborrhéiques (verrues séborréiques)(verrues séniles)(taches de vieillesse)

Traitements (pour les professionnels)

Treatment (For Professionals) How is seborrheic keratosis amenable to treatment? Here follows a description some of the available and tried treatments and then a criticism of the methodology of all applied treatments follows: 1. Actual Guidelines According to Dubertret et al.( Thérapeutique dermatologique). the following treaments are recommended: – Cryotherapy with liquid nitrogen {Kee, 1967}…

Les kératoses séborrhéiques (verrues séborréiques)(verrues séniles)(taches de vieillesse)