Proceedings of the 2017 National Toxicology Program Satellite Symposium

Abstract

The 2017 annual National Toxicology Program Satellite Symposium, entitled “Pathology Potpourri,” was held in Montreal, Quebec, Canada, at the Society of Toxicologic Pathology's (STP) 36th annual meeting. The goal of this symposium was to present and discuss challenging diagnostic pathology and/or nomenclature issues. This article presents summaries of the speakers' talks, along with select images that were used by the audience for voting and discussion. Various lesions and other topics covered during the symposium included renal papillary degeneration in perinatally-exposed animals; an atriocaval mesothelioma; an unusual presentation of an alveolar bronchiolar carcinoma; a paraganglioma of the Organ of Zuckerkandl, also called an extra adrenal pheochromocytoma; the use of human muscle samples to illustrate the challenges of manual scoring of fluorescent staining; intertubular spermatocytic seminomas; medical device pathology assessment and discussion of the approval process; collagen induced arthritis; incisor denticles; ameloblast degeneration and poorly mineralized enamel matrix; connective tissue paragangliomas; microcystin LR toxicity; perivascular mast cells in the forebrain thalamus unrelated to treatment; and two cases that provided a review of the International Harmonization of Nomenclature and Diagnostic Criteria (INHAND) bone nomenclature and recommended application of the terminology in routine nonclinical toxicity studies.

Introduction to Digital Image Analysis in Whole-slide Imaging: A White Paper from the Digital Pathology Association

“…[6789] Similarly, a whole host of staining techniques (and combinations thereof) can be amendable to image analysis, not limited to routine hematoxylin and eosin (H and E) staining, IHC, or ISH labeling (chromogenic and fluorescent). [410111213]…”

Nonalcoholic fatty liver disease alters microcystin-LR toxicokinetics and acute toxicity

“…Microcystin-LR (MCLR) is a cyanotoxin produced by cyanobacteria (blue-green algae) and is known to cause both hepatic and renal toxicities. MCLR is classified as a high-priority drinking water contaminant by the Environmental Protection Agency, is the focus of several National Toxicology Program studies, and is the only microcystin that has been given a WHO tolerable daily intake value (0.04 μg/kg or 2.4 μg/day for a 60 kg person) (14,15). Consumption of microcystin-contaminated water and aquatic animals is the most frequent route of exposure and is well documented to occur around the world (16).…”

Spontaneous Primary Pleural Mesothelioma in Fischer 344 (F344) and Other Rat Strains: A Retrospective Review

“…Rat atriocaval mesotheliomas are also thought to develop from mesothelial or mesotheliallike cells but have a well-described distinct morphology, growth pattern, and localization (right atrial wall near the vena cava junction, or at the base of the interventricular septum) that distinguishes them from mesotheliomas arising elsewhere in the thoracic cavity. [32][33][34][35][36] Incidences of atriocaval mesothelioma of up to 20% have been reported in NZR/gd inbred rats, 35 but in other rat strains these neoplasms appear to be rare, with incidences of less than 1.0% reported in F344 32 and Sprague Dawley rats. 33,36 In contrast, there is limited information about nonatriocaval pleural/pericardial mesotheliomas in rats.…”