title: Dermoscopy of tumours arising in naevus sebaceous: a morphological study of 58 cases.
abstract: BACKGROUND
  Naevus sebaceous is a congenital hamartoma commonly associated with the development of secondary neoplasms. There are sparse data relating to the dermoscopy of tumours arising in naevus sebaceous.
  
  
  OBJECTIVE
  To evaluate the dermoscopic features of a large series of neoplasms arising in naevus sebaceous.
  
  
  METHODS
  Digital dermoscopic images of 58 histopathologically confirmed cases of secondary neoplasms arising in naevus sebaceous collected from 11 hospitals in Spain, France, Italy and Austria were evaluated for the presence of dermoscopic structures and patterns.
  
  
  RESULTS
  The most frequent tumours collected were: trichoblastoma (39.6%), basal cell carcinoma (20.7%) and syringocystadenoma papilliferum (15.6%). The most remarkable findings were: (i) the pattern composed of asymmetrical large blue-grey ovoid nests was more common in basal cell carcinomas than in trichoblastoma (58.3% vs. 4.3%; P < 0.001) and the pattern composed of a symmetrical total large blue-grey ovoid nest (a blue-grey homogeneous area which occupies the whole lesion) was more common in trichoblastoma (82.6% vs. 16.6%; P < 0.001); (ii) the most frequent pattern associated with syringocystadenoma papilliferum was a symmetric, erythematous lesion with exophytic papillary structures, ulceration and vessels (55.5%); (iii) the most common pattern associated with apocrine hidrocystomas was a total symmetric homogeneous area and arborizing telangiectasias (60%).
  
  
  CONCLUSIONS
  Benign adnexal tumours associated with naevus sebaceous are dermoscopic mimickers of basal cell carcinomas. A pigmented nodule arising in a naevus sebaceous with a total blue large ovoid nest on dermoscopy could be a trichoblastoma, basal cell carcinoma, hidrocystoma or hidradenoma. Dermoscopy can be a useful diagnostic tool which generates a more accurate preoperative diagnosis.
authors: Dermatology Department, Hospital Sant Pau i Santa Tecla, Tarragona, Spain.
authors: P
authors: P
authors: Zaballos
authors: Dermatology Department, Hospital Sant Pau i Santa Tecla, Tarragona, Spain.
authors: P
authors: P
authors: Serrano
authors: Unitat de Suport a la Recerca Tarragona-Reus, Institut Universitari d'Investigació en Atenció Primària Jordi Gol (IDIAP Jordi Gol), Tarragona, Spain.
authors: G
authors: G
authors: Flores
authors: Dermatology Department, Hospital Universitario de Alicante, Alicante, Spain.
authors: J
authors: J
authors: Bañuls
authors: Dermatology Department, Lyons Cancer Research Center, Lyon, France.
authors: L
authors: L
authors: Thomas
authors: Dermatology Department, Hospital de son Llatzer, Palma de Mallorca, Spain.
authors: A
authors: A
authors: Llambrich
authors: Dermatology Department, Hospital Universitario de Gran Canaria "Doctor Negrín", Gran Canaria, Spain.
authors: E
authors: E
authors: Castro
authors: Dermatology, Skin cancer unit, Arcipesdale Santa Maria Nuova, Regio Emilia, Italy.
authors: A
authors: A
authors: Lallas
authors: Dermatology Unit, Second University of Naples, Naples, Italy.
authors: G
authors: G
authors: Argenziano
authors: Dermatology Department, Medical Univeristy of Graz, Austria.
authors: I
authors: I
authors: Zalaudek
authors: Dermatology Department, Hospital Universitari Son Espases, Palma Mallorca, Spain.
authors: L J
authors: LJ
authors: del Pozo
authors: Dermatology, Surgical Department, Infermi Hospital, Rimini, Italy.
authors: C
authors: C
authors: Landi
authors: Dermatology Department, Hospital Clinic de Barcelona, Barcelona, Spain.
authors: J
authors: J
authors: Malvehy
mesh_terms: D018250:Acrospiroma / Q000473:pathology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D002280:Basal Cell Carcinoma / Q000473:pathology*; D002471:Cell Transformation, Neoplastic / Q000473:pathology; D002648:Child; D003537:Cystadenoma / Q000473:pathology*; D046169:Dermoscopy; D005260:Female; D018251:Hidrocystoma / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D054000:Nevus, Sebaceous of Jadassohn / Q000473:pathology*; D012626:Sebaceous Gland Neoplasms / Q000473:pathology*; D013544:Sweat Gland Neoplasms / Q000473:pathology*; D055815:Young Adult