title: Tissue microarrays are reliable tools for the clinicopathological characterization of lung cancer tissue.
abstract: BACKGROUND
  The advantage of tissue microarray (TMA) is its ability to efficiently analyze large numbers of tissue specimens in a methodologically uniform way. The reliability of TMAs, especially with regard to clinicopathological characterizations, when compared to conventional immunohistochemistry (IHC) was evaluated.
  
  
  METHODS
  Seventy-two embedded tissue sections from lung cancer specimens were stained with monoclonal antibodies against the tumor-associated markers TA-MUC1 and Lewis Y. Three representative cores of every tumor were embedded in a paraffin array multiblock. The IHC was evaluated by the immunoreactive score (IRS).
  
  
  RESULTS
  The data for the TMA IHC and the conventional IHC were concordant (kappa > or = 80%) for both markers. Likewise, discordance (McNemar's test) was low, and sensitivity and specificity were above 80% for both markers. In the samples with high positive expression, the concordance increased (kappa > or = 90%), discordance disappeared (McNemar p = 1.0), and sensitivity and specificity increased above 90% for both markers. Using Cox regression models, all the clinicopathological dependencies were equivalent for both techniques and both markers.
  
  
  CONCLUSIONS
  Immunohistochemistry with tissue microarrays is valid and provides results equivalent to conventional immunohistochemistry with respect to expression patterns and clinicopathological characterizations.
authors.affiliation: Pulmonary Division, III Medical Clinic, Johannes Gutenberg University, 55101 Mainz, Germany.
authors.forename: Lars Henning
authors.initials: LH
authors.lastname: Schmidt
authors.forename: Stefan
authors.initials: S
authors.lastname: Biesterfeld
authors.forename: Andreas
authors.initials: A
authors.lastname: Kümmel
authors.forename: Andreas
authors.initials: A
authors.lastname: Faldum
authors.forename: Martin
authors.initials: M
authors.lastname: Sebastian
authors.forename: Christian
authors.initials: C
authors.lastname: Taube
authors.forename: Roland
authors.initials: R
authors.lastname: Buhll
authors.forename: Rainer
authors.initials: R
authors.lastname: Wiewrodt