title: Folliculosebaceous cystic hamartoma or trichofolliculoma? A spectrum of hamartomatous changes inducted by perifollicular stroma in the follicular epithelium.
abstract: BACKGROUND
  Folliculosebaceous cystic hamartoma (FSCH) histologically resembles trichofolliculoma.
  
  
  METHODS
  The clinical and histologic characteristics of both tumors were studied retrospectively, comparing these findings with those of other similar follicular tumors described in the literature.
  
  
  RESULTS
  Fourteen cases of FSCH and 15 cases of trichofolliculoma were diagnosed over 5 years. FSCH were larger, of longer duration, located mostly in the head and neck region. Histologically, the two lesions had a similar architecture except for the presence of a secondary follicle in trichofolliculoma.
  
  
  CONCLUSIONS
  FSCH are probably more common than previously thought and may be part of a spectrum of cystic follicular tumors. The perifollicular stroma may influence differentiation of the cystic wall, resulting in a variety of follicular tumors with overlapping features.
authors.affiliation: Department of Dermatology, Mackay Memorial Hospital, Mackay Medicine, Nursing and Management College, Taipei, Taiwan. yuhung_wu@yahoo.com
authors.forename: Yu-Hung
authors.initials: YH
authors.lastname: Wu
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006201:Hair Diseases / Q000473:pathology*; D018859:Hair Follicle / Q000473:pathology*; D006222:Hamartoma / Q000175:diagnosis*; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012627:Sebaceous Glands / Q000473:pathology*