Rapid and large-scale transition of new tumor biomarkers to clinical biopsy material by innovative tissue microarray systems.

A rapidly increasing number of studies are being published providing significant results by the use of tissue microarrays (TMAs), ie, paraffin blocks composed of multiple specimens. The numerous advantages of this technology are obvious and have thus stimulated many constructors to evolve and improve different technical approaches. With TMAs, multiple specimens can be simultaneously investigated with different in situ techniques under identical laboratory conditions, resulting in a dramatic time and cost reduction compared with conventional pathologic studies. Furthermore, this technology is less exhausting for the finite original donor material, allowing for a significantly increased number of assays per each case. Against the background of decoding the human genome and the widespread application of high-density cDNA microarrays, the next challenge will be to apply the genome discoveries to the clinical setting. For pathologists, TMAs represent an ideal adjunct and can be very useful for the rapid and high-throughput discovery and validation of countless candidate biomarkers, assessing their prognostic and predictive value and identifying further therapy targets. This article provides a review of different TMA technologies and addresses the technical aspects of their construction and their validity in different applications through data from the literature along with the authors' own experiences.