Category: Uncategorized
Approaches to Design-Based Stereology
In contrast to two-dimensional image analysis, the goal of modern design-based stereology is to provide an unbiased estimate of the absolute number or size of measured objects within a three-dimensional region of interest, as opposed to a relative value (e.g., number of objects per unit area, i.e., density). This approach allows valid comparisons to be […]
Pathology Working Groups (PWG) Conducted by EPL
A Pathology Working Group (PWG) is a specialized type of review composed of a group of expert pathologists convened to answer specific questions and provide an independent unbiased opinion regarding study results. They may be convened by study sponsors, consortiums, or government agencies. Members of the PWG may come from academia, government, or industry and […]
Pathology Peer Review
The main purpose of a Pathology Peer Review is to improve the quality of the pathology data and narrative. This can be achieved in several ways. A peer review can help to ensure that the data are presented in a manner that meets the requirements of the regulatory agency to which the data will be […]
Is the Lesion Adverse or Not?
Determining whether or not a pathologic finding should be regarded as adverse has posed a conundrum for histopathologists for longer than I have been in the business. Much of the problem stemmed from the lack of a workable definition of adverse that could be useful to the pathologist and toxicologist and also acceptable to regulatory […]
Value of Pathology Working Groups (PWG) at EPL
Although a Sponsor can never know exactly how a regulatory authority will respond to toxicity data, there are great examples of how a Pathology Working Group (PWG) can be beneficial. Recently, the study pathologist for a mouse carcinogenicity study identified a relatively low number of renal tumors that raised the concern of the involved regulatory […]