title: Expression of c-Met Is Different along the Location and Associated with Lymph Node Metastasis of Head and Neck Carcinoma.
abstract: BACKGROUND
  Activation of the c-Met pathway is involved in cancer progression and the prognosis. We aimed to identify any association of c-Met protein expression with a number of clinicopathologic variables including infection of human papillomavirus and Epstein-Barr virus (EBV) in head and neck carcinomas (HNCa).
  
  
  METHODS
  Eighty-two cases were enrolled in this study. Expression of c-Met and p16 was investigated immunohistochemically. EBV was detected by in situ hybridization and amplification of the c-Met gene by fluorescence in situ hybridization.
  
  
  RESULTS
  The c-Met protein was expressed in 41.5% (34/82), and gene amplification was found in 1.4% (1/71). High expression of c-Met was associated with the primary location of the tumor; the hypopharynx showed the highest expression, followed by the oral cavity, larynx, and nasal cavity. Squamous cell carcinoma expressed c-Met more frequently than undifferentiated carcinoma. Also, p16 immunoreactivity or EBV infection was associated with the tumor location and well-differentiated histologic type, but were not linked to c-Met expression. The patients with positive c-Met expression showed frequent lymph node metastasis.
  
  
  CONCLUSIONS
  Activation of the c-Met pathway might be involved in a subset of HNCa. Cases showing positive c-Met expression should be carefully monitored because of the high probability of lymph node metastasis.
authors: Department of Pathology, Seoul National University Boramae Hospital, Seoul National University College of Medicine, Seoul, Korea.
authors: Ji-Young
authors: JY
authors: Choe
authors: Ji Yun
authors: JY
authors: Yun
authors: Soo-Jeong
authors: SJ
authors: Nam
authors: Ji Eun
authors: JE
authors: Kim
keywords: Carcinoma, squamous cell; Gene amplification; Head and neck neoplasms; Human papillomavirus; Proto-oncogene proteins c-met