title: Hematogenous cytokeratin 20 mRNA detection has prognostic impact in oral squamous cell carcinoma: preliminary results.
abstract: BACKGROUND
  The study was designed to detect disseminated tumor cells (DTCs) in postoperative peripheral blood of patients with oral squamous cell carcinoma (OSCC) and to determine their relevance as prognostic markers by cytokeratin (CK) expression analysis.
  
  
  METHODS
  Forty samples of peripheral blood mononuclear cells (PBMCs) isolated 4 weeks after surgery were screened for occurrence of four CK mRNA transcripts by real-time quantitative RT qPCR. Detection of mRNA expression was compared with clinicopathological parameters and disease-free survival (DFS).
  
  
  RESULTS
  CK 17 and CK 19 could not be detected in any samples. CK 18 and CK 20 were detectable in 1 (2.5%) and in 14 (35.0%), respectively. The detection of CK 20 was not significantly associated with lymph node status, clinical stage, or differentiation grade, but was significantly higher in patients with T3 and T4 OSCC (p = 0.04). DFS was not associated with tumor size, clinical stage, or differentiation grade. But poor DFS was significantly associated with the occurrence of lymph node metastasis (p = 0.01) and detection of CK 20 (p = 0.01).
  
  
  CONCLUSIONS
  DTCs in PBMCs of postoperative patients with OSCC could only be detected by determination of CK 20 mRNA. Detection of CK 20 mRNA in peripheral blood seems to be of relevance for prognosis in OSCC.
authors.affiliation: Department of Oral and Maxillofacial Surgery, University of Erlangen-Nuremberg, Erlangen.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Toyoshima
authors.forename: Eleftherios
authors.initials: E
authors.lastname: Vairaktaris
authors.forename: Emeka
authors.initials: E
authors.lastname: Nkenke
authors.forename: Karl Andreas
authors.initials: KA
authors.lastname: Schlegel
authors.forename: Friedrich Wilhelm
authors.initials: FW
authors.lastname: Neukam
authors.forename: Jutta
authors.initials: J
authors.lastname: Ries