Citation:

Wood, C. Interpretive issues for thyroid follicular cell hypertrophy and hyperplasia at the U.S. EPA. 6th ESTP International Expert Workshop, Berlin, GERMANY, GERMANY, May 16 - 17, 2018.

Impact/Purpose:

There is currently a need for better alignment among toxicologic pathologists and regulatory scientists regarding how adversity is determined and characterized. To help address this issue, the European Society of Toxicologic Pathology (ESTP) coordinated an expert workshop focused on adversity considerations related to thyroid follicular cell hypertrophy and hyperplasia, which are common effects of chemical exposure that can have important implications for risk assessment. The attached slides will be presented as a webinar only to workshop participants. The primary goals of this workshop are (1) to develop a better understanding of the pathways/modes of action leading to follicular cell hypertrophy and hyperplasia and potential functional consequences; (2) to provide criteria to assess adversity of histopathologic findings associated with thyroid toxicity; and (3) to describe methods and experimental considerations to further inform adversity decisions related to follicular cell hypertrophy and hyperplasia. The panel for this workshop is comprised of representatives from the European Union, Japan, and the US. Participants will share practical case examples to illustrate issues related to assessing the adversity of thyroid changes. The final output of the workshop will be a summary report of case presentations and discussions at a face-to-face meeting in May 2018. Recommendations of this workshop should increase consistency in the interpretation of adversity based on pathology findings in nonclinical studies, help integrate new types of molecular data into the review process, and facilitate a more systematic approach to communicating adversity calls in toxicology reports.

Description:

NA. See impact statement above.

Record Details: