Method Validation: Evaluation of the Analytical Performance of Standard Hematoxylin-Eosin Staining

Introduction The optimization of diagnostic quality is a major issue in Pathological Anatomy and Cytology (ACP) to secure analytical circuits and protect the operational flow of histological analyses and molecular biology examinations. The objective of this work is to validate the analytical performance of standard hematoxylin-eosin (H.E) staining according to the evaluation criteria of slides in the laboratory.  Materials and Methods Method validation involves numerous steps requiring close collaboration between pathologists and technicians. For our study, the validation covered performances such as inter-technician variability, inter- pathologist variability, and inter-block contamination. The study included 4 paraffin-embedded blocks from 2 surgical specimens, each block being sectioned by 4 different technicians on 4 different microtomes. The 16 obtained sections were stained and read by 2 expert pathologists.  Results Across the 7 evaluation criteria, a preliminary concordance of 98 % was generally found, with no differences impacting the diagnosis.  Conclusion The process of qualitative method validation in ACP is complex due to the multiplicity of stakeholders, the presence of several sub-processes, the difficulty in managing interfaces, and the desire to align with current regulations as a reference site (ISO 20166-4/2021 standard).4. Nevertheless, it is necessary within a quality assurance approach.