title: Reflectance confocal microscopy correlates of dermoscopic patterns of facial lesions help to discriminate lentigo maligna from pigmented nonmelanocytic macules.
abstract: BACKGROUND
  The clinical recognition of lentigo maligna (LM) and LM melanoma can be very challenging due to the overlapping features it shares with other pigmented macules of the skin. Noninvasive diagnostic techniques can assist in the differential diagnosis.
  
  
  OBJECTIVE
  To identify reflectance confocal microscopy (RCM) indicators for LM through the identification of in vivo microscopic substrates of the main dermoscopic features seen in flat pigmented lesions of the face.
  
  
  METHODS
  Retrospective analysis of 60 pigmented lesions (LM, invasive melanoma, solar lentigo/flat seborrhoeic keratosis, lichen planus-like keratosis, pigmented actinic keratosis) was carried out. The main dermoscopic patterns and RCM features were described. A new method for correlating RCM with dermoscopic patterns was developed.
  
  
  RESULTS
  Pseudonetwork (37 of 60 lesions) and annular granular structures (37 of 60 lesions) were the most frequent dermoscopic patterns, followed by pigmented blotches (27 of 60 lesions). Upon RCM examination, pseudonetwork and blotches differed in melanomas and other nonmelanocytic lesions. These differences included the intraepidermal proliferation of atypical cells (predominantly dendritic-shaped with adnexal tropism) and the presence of a meshwork pattern at the junction. Also, annular granular structures exhibited dendritic cells almost exclusively in melanoma, with no difference between melanomas and nonmelanocytic lesions for the junctional and upper dermal pattern (characterized by dermal inflammation). Fingerprinting was mostly present in nonmelanocytic lesions or corresponded to an overlap with solar lentigo in melanomas.
  
  
  CONCLUSIONS
  RCM is useful for identifying the histological substrate of dermoscopic features in pigmented lesions of the face. It can provide a better definition of the lesion areas, enabling an improved diagnostic approach.
authors.affiliation: Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy.
authors.forename: N
authors.initials: N
authors.lastname: de Carvalho
authors.affiliation: Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Farnetani
authors.affiliation: Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Ciardo
authors.affiliation: Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Ruini
authors.affiliation: Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy.
authors.forename: A M
authors.initials: AM
authors.lastname: Witkowski
authors.affiliation: Dermatology and Skin Cancer Unit, Arcispedale Santa Maria Nuova, Istituto di Ricovero e Cura a Carattere Scientifico-IRCCS, Reggio Emilia, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Longo
authors.affiliation: Dermatology and Skin Cancer Unit, Arcispedale Santa Maria Nuova, Istituto di Ricovero e Cura a Carattere Scientifico-IRCCS, Reggio Emilia, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Argenziano
authors.affiliation: Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Pellacani
mesh_terms: D012628:Dermatitis, Seborrheic / Q000473:pathology; D046169:Dermoscopy / Q000379:methods; D003937:Diagnosis, Differential; D005148:Facial Dermatoses / Q000473:pathology; D005153:Facial Neoplasms / Q000473:pathology*; D006801:Humans; D018327:Hutchinson's Melanotic Freckle / Q000473:pathology*; D055623:Keratosis, Actinic / Q000473:pathology; D008010:Lichen Planus / Q000473:pathology; D008545:Melanoma / Q000473:pathology; D018613:Microscopy, Confocal / Q000379:methods; D010859:Pigmentation Disorders / Q000473:pathology*; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000473:pathology*