The College of American Pathologists (CAP) has updated its evidence-based guideline for analytic validation of immunohistochemical (IHC) assays to provide increased accuracy and consistency in laboratory practices.
Many of the recommendations published in the original 2014 guideline have remained the same. However, there are new recommendations and modifications in the update developed through assessing evidence published after the guideline’s 2014 release, according to a CAP statement.
New recommendations include those providing guidance for validation and verification of IHC assays performed on cytology specimens and predictive marker assays that have distinct scoring systems, such as programmed death receptor-1 (PD-L1). Additionally, while the 2014 guideline outlined distinct requirements for validation and verification of HER2, ER, and PR predictive markers, the update harmonizes the validation requirements for all predictive markers.
The updated guideline may be found as an early release on the Archives of Pathology & Laboratory Medicine site. Current information, a FAQ, and tools and resources for the updated guideline may be found on CAP’s website.
