The 2025 annual Division of Translational Toxicology (DTT) Satellite Symposium, entitled ‘‘Pathology Potpourri’’ was held in Chicago, IL, at the Society of Toxicologic Pathology’s (STP) 44th annual meeting. This year marked the 25th anniversary of the DTT Satellite Symposium. The goal of this symposium was to present and discuss challenging or interesting diagnostic pathology and/or nomenclature issues. This article presents summaries of the speakers’ talks along with select images and data that were used by the audience for voting and discussion. Various lesions and topics covered during the symposium included inflammatory lung lesions in rats due to inhalation of silica dust; excipient-related renal tubular vacuolation in rats; spheroids in the cerebellum of dogs associated with administration of an O-GlcNAc inhibitor; hyperplasia and papillomas in the bladder of mice treated with a fragrance component; hematology analyzer error flags related to increased numbers of large unstained cells (LUCs), as well as analyzer dysfunction in the measurement of the white blood cell (WBC) count and differential, paradoxical effect of cyclosporine in allergic lung inflammation in mice, and vertebral deformation and gas gland adenomas in killifish.
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