CAP TODAY Pathology/Laboratory Medicine/Laboratory Management
Harris S. Goodman, MD
Richard M. Scanlan, MD
Emily E. Volk, MD
December 2021—The CAP has decided to temporarily withdraw the anatomic pathology checklist requirement ANP.10039 (Total Fixation Time) from the 2021 checklist edition, and this requirement will no longer appear in customized checklists provided to laboratories and inspectors using the 2021 edition.
The decision was based on further review of the requirement by the CAP’s Checklists Committee and Commission on Laboratory Accreditation in response to concerns that CAP-accredited laboratories and CAP scientific committee members expressed about the scientific data supporting the requirement and the feasibility of compliance.
The original intent in adding ANP.10039 to the 2021 checklist edition was to minimize preanalytic variables related to specimen fixation that detrimentally affect the quality of pathology specimens and ultimately have an impact on the downstream results of tests used for patient care and precision medicine. The total fixation time in formalin has been shown to impact the quality of nucleic acids extracted for molecular testing, protein recovery for mass spectroscopy, and immunoreactivity of proteins. Inadequate fixation may lead to hydrolysis, formalin-induced mutation, and DNA/RNA fragmentation. ANP.10039 required laboratories to have a process to ensure optimal total fixation time in formalin for specimens clinically suspected (as stated on the requisition) or otherwise known to contain malignancy that are likely to be submitted for ancillary testing, such as breast and gastroesophageal carcinomas. The following statements in the requirement note were the area of concern for this requirement: “A total fixation time at room temperature of no less than six hours and no greater than 36 hours is required for most tissues. Tissues with high fat content can be fixed up to 48 hours.”