Proceedings of the 2024 Classic Examples in Toxicologic Pathology XXXI

Area of Science:

• Veterinary Pathology
• Toxicologic Pathology
• Experimental Pathology

Background:

• The European Society of Toxicologic Pathology (ESTP) jointly organizes a slide seminar series.
• The seminar "Classic Examples in Toxicologic Pathology" presents and discusses classical and novel cases.
• This article reviews 6 selected presentations from the 31st seminar held in March 2024.

Purpose of the Study:

• To summarize key findings from selected presentations at the toxicologic pathology seminar.
• To illustrate representative lesions from cases involving test item-induced pathology.
• To provide insights into diverse toxicologic pathology mechanisms and outcomes.

Main Methods:

• Review of 6 presentations from the "Classic Examples in Toxicologic Pathology" seminar.
• Inclusion of images depicting representative pathological lesions.
• Summarization of findings related to specific test items and their effects.

Main Results:

• Progesterone receptor antagonist linked to uterine tumor development in rats.
• Hybridization-dependent off-target hepatotoxicity observed with N-acetylgalactosamine (GalNAc)-conjugated small interfering RNA (siRNA) in rats.
• Orexin-1/-2 receptor antagonist associated with liver enzyme induction.
• Cases involving reactive metabolites, GPR40 agonist effects, and dysgeusia were also presented.

Conclusions:

• The presented cases highlight diverse mechanisms of chemically induced pathology.
• Understanding these examples is crucial for accurate toxicologic pathology assessment.
• The seminar serves as a valuable platform for discussing complex cases in the field.