title: [Circumscribed palmar hypokeratosis (CPM): The diagnostic value of dermoscopy].
abstract: BACKGROUND
  Circumscribed palmar hypokeratosis (CPH) is a rare skin disease, first described in 2002, associated with sudden localized reduction of the corneal layer. In most cases, it presents as an isolated rounded erythematous palmar lesion on the thenar eminence. We describe the dermoscopic semiology of CPH in 3 cases.
  
  
  METHODS
  Three patients between the ages of 59 and 72 presented very limited erythematous lesions suggestive of CPH. Dermoscopic examination of these lesions provided similar findings. Biopsy, which was performed in one patient, confirmed the diagnosis of CPH.
  
  
  RESULTS
  Two dermoscopic elements of CPH are characteristic: (1) the sides of the lesion have a "stair step" or "geological strata" type of configuration, and the thickness of the different strata varies; (2) the centre of the lesion showed a homogeneous erythematous area with a vascular pattern composed of dotted vessels of the superficial dermis and sometime vascular loops.
  
  
  CONCLUSIONS
  These dermoscopic aspects are characteristic and enable CPH to be differentiated from Bowen's disease or porokeratosis of Mibelli. In Bowen's disease, there is no stair step like aspect to the sides of lesions; further, the centre of the lesion shows glomerular vessels (coiled vessels) and/or globular vessels (small red clods). In porokeratosis, peripheral keratotic "white track" structures comprise a single pigmented channel or a double white line. There is no "stair step" or central vascular pattern.
  
  
  CONCLUSIONS
  The dermoscopic semiology of CPH is highly characteristic and enables differentiation from Bowen's disease and porokeratosis.
authors: Service de dermatologie, CHU d'Angers, 4, rue Larrey, 49933 Angers cedex 9, France.
authors: S
authors: S
authors: Topin-Ruiz
authors: Cabinet de dermatologie, 11, rue Georges-Clemenceau, 49300 Cholet, France.
authors: J-M
authors: JM
authors: Debarre
authors: Cabinet de dermatologie, 11, rue Georges-Clemenceau, 49300 Cholet, France.
authors: E
authors: E
authors: Blanchard
authors: Centre de pathologie de l'Ouest, BP 40428, 49004 Angers cedex 01, France.
authors: S
authors: S
authors: Kettani
authors: Cabinet de dermatologie, résidence Clos Des Halles, 26, boulevard Colonel-Aubry, 79300 Bressuire, France.
authors: P-J
authors: PJ
authors: Valmier
authors: Service de dermatologie, CHU d'Angers, 4, rue Larrey, 49933 Angers cedex 9, France.
authors: L
authors: L
authors: Martin
authors: Service de dermatologie, CHU d'Angers, 4, rue Larrey, 49933 Angers cedex 9, France. Electronic address: yalecorre@chu-angers.fr.
authors: Y
authors: Y
authors: Le Corre
mesh_terms: D000368:Aged; D001706:Biopsy; D046169:Dermoscopy; D003937:Diagnosis, Differential; D005260:Female; D006229:Hand Dermatoses / Q000473:pathology*; D006801:Humans; D008875:Middle Aged
keywords: Bowen's disease; Circumscribed palmar or plantar hypokeratosis; Dermoscopie; Dermoscopy; Disseminated superficial actinic porokeratosis; Hypokératose acrale circonscrite; Maladie de Bowen; Porokeratosis of Mibelli; Porokératose de Mibelli