Reliability of Tissue Microarrays for Immunohistochemical Detecting of Tumor Markers in Non-Small Cell Lung Cancer

Objective Tissue microarrays allow high throughput molecular profiling of cancer specimens by immunohistochemistry. This study is aimed at investigating the reliability and validity of tissue microarrays for immunophenotyping.Methods We constructed triplicate tissue microarrays (TMAs) containing specimens from 418 patients with non small cell lung cancer (NSCLC), and randomized selected 50 full tissue sections from these tumors. TMAs and full tissue section slides were immunohistochemically stained with antibodies against Ki 67 and p53. Data on full tissue sections were compared to the results of TMAs.Results Concordance for Ki 67 and p53 staining between tissue arrays with triplicate cores per tumor and full sections were 98% and 96%, respectively. TMAs (three cores per tumor) were reliable for detecting of Ki 67 and p53 in NSCLC tissues, Kappa value were 0.95 and 0.91 , respectively.Conclusion Triplicate 0.6 -mm core biopsies sampled on tissue arrays provide a reliable system for high throughput expression profiling by immunohistochemistry when compared to standard full sections, and suit for large scale retrospective clinical study.