Microscope? No, thanks: Use of Whole Slide Images (W.S.I.’s) in Toxicologic Pathology in the Evaluation of Non-clinical GLP-Studies

In category: Publication
发布日期: 2023 1 2 月
阅读时间: 3 minutes

Regulatory recommendations and perspective for routine diagnoses

Nowadays, the application of Digital Pathology (DP) (histopathological evaluation using scans of glass slides), when well performed by the pathologist, can match equally with conventional light microscopy in toxicologic pathology for the safety evaluation in toxicology studies in the development of new vaccines, medicines and chemicals. Much research has now proven already that the quality evaluation by using digital slides (WSI – “Whole Slide Imaging”) is not significantly different in their quality for evaluation for many organ systems.

In 2017, digital whole slide imaging (W.S.I.) for primary diagnosis in pathology was approved by the US Food and Drug Administration (FDA), paving the way for widespread adoption of this technology in everyday practice. In both clinical and veterinary (toxicologic) pathology elaborate investigations and publications on DP, using whole slide images for histopathology assessment, and for several organ systems support this use of DP.

The “OECD Good Laboratory Practice: Frequently asked questions (FAQ)” from June, 2022 states on Digital Histopathology: “The OECD Principles of GLP do not preclude the use of digitized histopathology slides in GLP studies for the histopathological assessment of tissue samples. This would include the initial read of tissue slides by the study pathologist and histopathology peer reviews, either prospectively or retrospectively”.

At Global Pathology Support B.V. (GPS BV) we tested/validated the use of digital pathology evaluation, in comparison with conventional light microscopy histopathology assessment. The result was that Whole Slide Images (W.S.I.’s) are non-inferior to traditional glass slides for primary diagnosis in toxicologic pathology. No significant difference in diagnostic accuracy between viewing modalities was found. So, both options: conventional histopathology (LM) and digital pathology evaluation (DP) are now available in a GLP-compliant manner. When using the digital slide reading the GPS Slide Suite/Platform will be applicable for the storage and retrieval of slides.

The EU is a signatory to the OECD mutual acceptance of data (MAD – Mutual Acceptance of Data) agreement, which allows participating authorities to rely on each other’s monitoring programs for GLP compliance .

As GPS BV is compliant with GLP, this also means that pathology data generated from GPS BV meets GLP-Compliance and have to be accepted by all 38 OECD member countries.


OECD Digital Histopathology – Is there any objection from the GLP compliance monitoring authorities to implement digital pathology in GLP studies? (June 15, 2022)

U.S. Department of Health and Human Services. Food and Drug Administration Use of Whole Slide Imaging in Nonclinical Toxicology Studies: Questions and Answers – Guidance for Industry – DRAFT GUIDANCE – April 2022

Evans AJ, Brown RW, Bui MM, et al. Validating Whole Slide Imaging Systems for Diagnostic Purposes in Pathology. Archives of pathology & laboratory medicine 2022;146(4):440-450.