J Clin Pathol 59:445-453 doi:10.1136/jcp.2003.007641
  • Review

Molecular biology of squamous cell carcinoma of the head and neck

  1. B Perez-Ordoñez1,
  2. M Beauchemin2,
  3. R C K Jordan3
  1. 1Department of Pathology, University Health Network, and Department of Pathobiology and Laboratory Medicine, University of Toronto, Toronto, Ontario, Canada
  2. 2Department of Pathology, Hôpital du Saint-Sacrement, Centre Hospitalier afflilié Universitaire de Québec, Quebec, Canada
  3. 3Department of Orofacial Sciences and Department of Pathology, University of California, San Francisco, California, USA
  1. Correspondence to:
 Dr Bayardo Perez-Ordoñez
 Department of Pathology, University Health Network, Princess Margaret Hospital, 610 University Avenue, Toronto, Ontario M4N 3M5, Canada; bayardo.perez-ordonez{at}
  • Accepted 25 November 2005


Squamous cell carcinoma of the head and neck (HNSCC) is a heterogeneous but largely preventable disease with complex molecular abnormalities. It arises from a premalignant progenitor followed by outgrowth of clonal populations associated with cumulative genetic alterations and phenotypic progression to invasive malignancy. These genetic alterations result in inactivation of multiple tumour suppressor genes and activation of proto-oncogenes, including p16ink4A, p53, cyclin D1, p14ARF, FHIT, RASSF1A, epidermal growth factor receptor (EGFR), and Rb. Intramucosal migration and clonal expansion of transformed cells with formation of abnormal genetic fields appear to be responsible for local recurrences and development of second primary tumours.