Validation of usefulness of tissue microarray technology in primary tumours of the canine and feline central nervous system.

High-throughput tissue microarray (TMA) technology allows analysis of many specimens of tumours simultaneously on a single slide. One potential limitation of TMAs is the correct representation of each tumour with the small tissue core. The aim of this study was to validate TMA technology for 10 primary tumours of the canine and feline central nervous system (CNS) by comparing histology and immunohistochemical labelling of duplicate core biopsies on TMA with the results of full-section analysis. Concordance between results was not rejected by using paired student's t-test. The accuracy of the TMA technology of sampling a representative tumour area was 95% without significant differences in various histological parameters. The loss of ∼0.9% of tissue cores during histological and immunohistochemical processing was very low. There were no significant differences in immunohistochemical labelling between the two tissue cores, between the mean score of both tissue cores and the conventional tissue section and between each tissue core alone compared with the full tissue section. This investigation confirms the applicability of the TMA technology for primary CNS tumours of dogs and cats.