Merdol Ibrahim1, Suzanne Parry2, Dawn Wilkinson2, Neil Bilbe2, David Allen3, Steven Forrest4, Perry Maxwell5, Anthony O'Grady6, Jane Starczynski7, Philippe Tanier8, John Gosney4, Keith Kerr9, Keith Miller2, Erik Thunnissen10. 1. U.K. National External Quality Assessment Scheme Immunocytochemistry and In Situ Hybridisation, University College London Cancer Institute, Research Department of Pathology, University College London, United Kingdom. Electronic address: merdol.ibrahim@ucl.ac.uk. 2. U.K. National External Quality Assessment Scheme Immunocytochemistry and In Situ Hybridisation, University College London Cancer Institute, Research Department of Pathology, University College London, United Kingdom. 3. University College London Advanced Diagnostics, Research Department of Pathology, University College London, United Kingdom. 4. Royal Liverpool University Hospital, Liverpool, United Kingdom. 5. Northern Ireland Molecular Pathology Laboratory, Belfast Health and Social Care Trust and Queen's University Belfast, Northern Ireland, United Kingdom. 6. Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin, Ireland. 7. Birmingham Heartlands Hospital, Birmingham, United Kingdom. 8. Queen Elizabeth Hospital, Birmingham, United Kingdom. 9. Aberdeen Royal Infirmary, Aberdeen, United Kingdom. 10. Department of Pathology, VU University Medical Center, Amsterdam, The Netherlands.
Abstract
INTRODUCTION: Diagnostic immunohistochemistry (IHC) is increasingly accepted as a screening method for anaplastic lymphoma receptor tyrosine kinase gene (ALK) rearrangements in NSCLC. We have sought to establish an ongoing robust external quality assessment process to gauge quality of anaplastic lymphoma kinase (ALK) IHC, which can have an impact on interpretation of patient samples. METHODS: Unstained tissue and cell line samples were distributed on a quarterly basis to participating laboratories from 30 countries. Participants stained the slide using their routine diagnostic ALK IHC method and returned the slide along with their in-house control and methodology details. Slides were assessed by a team of pathologists and scientists. RESULTS: Overall, there was a mean pass rate of 83% (range 71%-98%), with 38 variations in staining protocol. Methods included the following: the Roche D5F3 assay (65% of users, pass rate 93%); Novocastra 5A4 (15% of users, pass rate 65%); Cell Signaling Technology D5F3 (7% of users, pass rate 91%), and Dako ALK1 (5% of users, pass rate 50%). Choice of methodology directly affected final interpretation of distributed ALK-positive and ALK-negative NSCLC cases, which were correctly identified by 89% and 88% of participants, respectively. Antibody detection method was a contributing factor in false-negative staining results. The choice of laboratory controls was found to be unsuitable, and as such, in-house control recommendations are also provided. CONCLUSIONS: ALK IHC is a robust screening technique, but there is concern that some diagnostic laboratories are using inadequate staining methods, which has a direct impact on final interpretation. External assessment helps provide laboratories with continued confidence in their ALK IHC testing.
INTRODUCTION: Diagnostic immunohistochemistry (IHC) is increasingly accepted as a screening method for anaplastic lymphoma receptor tyrosine kinase gene (ALK) rearrangements in NSCLC. We have sought to establish an ongoing robust external quality assessment process to gauge quality of anaplastic lymphoma kinase (ALK) IHC, which can have an impact on interpretation of patient samples. METHODS: Unstained tissue and cell line samples were distributed on a quarterly basis to participating laboratories from 30 countries. Participants stained the slide using their routine diagnostic ALK IHC method and returned the slide along with their in-house control and methodology details. Slides were assessed by a team of pathologists and scientists. RESULTS: Overall, there was a mean pass rate of 83% (range 71%-98%), with 38 variations in staining protocol. Methods included the following: the Roche D5F3 assay (65% of users, pass rate 93%); Novocastra 5A4 (15% of users, pass rate 65%); Cell Signaling Technology D5F3 (7% of users, pass rate 91%), and Dako ALK1 (5% of users, pass rate 50%). Choice of methodology directly affected final interpretation of distributed ALK-positive and ALK-negative NSCLC cases, which were correctly identified by 89% and 88% of participants, respectively. Antibody detection method was a contributing factor in false-negative staining results. The choice of laboratory controls was found to be unsuitable, and as such, in-house control recommendations are also provided. CONCLUSIONS:ALK IHC is a robust screening technique, but there is concern that some diagnostic laboratories are using inadequate staining methods, which has a direct impact on final interpretation. External assessment helps provide laboratories with continued confidence in their ALK IHC testing.
Authors: Max Robinson; Jacqueline James; Gareth Thomas; Nicholas West; Louise Jones; Jessica Lee; Karin Oien; Alex Freeman; Clare Craig; Philip Sloan; Philip Elliot; Maggie Cheang; Manuel Rodriguez-Justo; Clare Verrill Journal: J Pathol Clin Res Date: 2018-11-29
Authors: Cleo Keppens; Véronique Tack; Nils 't Hart; Lien Tembuyser; Ales Ryska; Patrick Pauwels; Karen Zwaenepoel; Ed Schuuring; Florian Cabillic; Luigi Tornillo; Arne Warth; Wilko Weichert; Elisabeth Dequeker Journal: Oncotarget Date: 2018-04-17