RT Journal Article SR Electronic T1 Validation of tissue microarray technology in malignant peripheral nerve sheath tumours JF Journal of Clinical Pathology JO J Clin Pathol FD BMJ Publishing Group Ltd and Association of Clinical Pathologists SP 629 OP 633 DO 10.1136/jcp.2008.063081 VO 62 IS 7 A1 Cunha, K Soares Gonçalves A1 Caruso, A Cunha A1 Gonçalves, A Soares A1 Bernardo, V Gonçalves A1 Pires, A Rodrigues Cordovil A1 da Fonseca, E Carvalho A1 de Faria, P Antônio Silvestre A1 da Silva, L Esmeraldo A1 Geller, M A1 de Moura-Neto, R Soares A1 Lopes, V Silami YR 2009 UL http://jcp.bmj.com/content/62/7/629.abstract AB Background: It has been suggested that the donor tissue cores used in tissue microarrays (TMAs) may not be representative of the whole tissue section.Aim: To validate the use of TMA technology in the study of malignant peripheral nerve sheath tumours (MPNSTs).Methods: A TMA was constructed containing five independent core biopsy samples of 14 formalin-fixed, paraffin-embedded MPNSTs. The immunohistochemical (IHC) results of the five cores from the same tissue block on TMA were compared with readings from whole sections using two antibodies: anti-Ki-67 and anti-S-100. Digital image analysis was performed to calculate the percentage of positive stain areas. The agreement between IHC results obtained with TMA cores and whole sections was assessed using the κ statistic.Results: There was good to very good agreement between IHC results for whole and TMA sections from MPNSTs. In relation to S-100, very good agreement (92% agreement; κ = 0.77) was observed using a minimum of four TMA cores. Staining results for Ki-67 from at least four readable TMA cores were the same as those for the whole section in 86% of cases, with good agreement, using weighted κ statistics (κ = 0.63).Conclusions: This study indicates that the TMA technique can be used in the IHC study of MPNSTs, even with the use of heterogeneous markers such as S-100 protein.