title: Branchial cyst carcinoma revisited: stem cells, dormancy and malignant transformation.
abstract: OBJECTIVE
  Branchial cleft cysts are among the most common causes for a congenital neck mass. Branchial cleft cyst carcinoma (BCCC) is a type of cancer that arises from cells within these cysts. Despite the distinct criteria that have been reported for its diagnosis, BCCC remains a controversial entity.
  
  
  METHODS
  We report a case of type I, first BCCC, on a 71-year-old white man. The diagnosis was based on the proposed criteria following lesion history and location, surgical excision, histology, and panendoscopy.
  
  
  CONCLUSIONS
  We argue for the first time the hypothesis that congenital branchial cysts and BCCC tumors may result from progenitor cell rests of the embryological branchial development. After a period of dormancy, these cells could eventually awake and proliferate, thus giving rise to branchial cleft cysts. With the acquirement of mutations due to genomic instability, some clones of these cells could transform to malignant stem cells, thus clinically manifesting as BCCC.
  
  
  CONCLUSIONS
  The wide recognition of stem cells and their role in carcinogenesis provides a new context for the etiopathogenesis of controversial and rare entities such as the BCCC.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, G Papanikolaou General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Vasileios
authors.initials: V
authors.lastname: Banikas
authors.forename: Athanassios
authors.initials: A
authors.lastname: Kyrgidis
authors.forename: Georgios
authors.initials: G
authors.lastname: Koloutsos
authors.forename: Leonidas
authors.initials: L
authors.lastname: Sakkas
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Antoniades
mesh_terms: D000368:Aged; D001935:Branchioma / Q000151:congenital / Q000175:diagnosis* / Q000601:surgery*; D002471:Cell Transformation, Neoplastic; D003937:Diagnosis, Differential; D003952:Diagnostic Imaging; D017809:Fatal Outcome; D006258:Head and Neck Neoplasms / Q000175:diagnosis* / Q000601:surgery*; D006801:Humans; D008297:Male; D013234:Stem Cells / Q000473:pathology