NORTHFIELD, Ill. (September 16, 2026)—New updates to the College of American Pathologists’ (CAP) Cancer Protocols will affect breast cancer biomarker reporting and molecular testing for gastrointestinal stromal tumors (GISTs), reflecting advances in precision oncology and laboratory accreditation. The updates are part of revisions to 14 Cancer Protocols designed to align cancer reporting with evolving World Health Organization (WHO) classifications and advances in precision medicine.
Among the most significant changes, the Breast Phyllodes Tumor protocol is now required for accreditation when reporting malignant phyllodes tumors. The revised protocol incorporates WHO 6th Edition updates, modifications to reporting elements, and updates to staging and margin reporting.
The Q3 release also includes important updates to the Breast Biomarker Protocol, including revisions to estrogen receptor (ER), progesterone receptor (PgR), and HER2 scoring and reporting criteria. The changes are designed to support consistent reporting of biomarkers that help guide breast cancer treatment decisions.
In addition, the CAP expanded molecular testing and reporting capabilities within its GIST protocols. Updates include new reporting options for NTRK fusion gene analysis as well as enhancements to KIT and PDGFRA biomarker testing and reporting. The revised protocols now also support reporting for GISTs across all anatomic sites.
CAP Cancer Protocols are updated quarterly to reflect evolving guidance from leading standard-setting organizations, including the WHO and the American Joint Committee on Cancer (AJCC). These evidence-based tools help pathologists deliver accurate, standardized cancer reports that support diagnosis, staging, treatment decisions, and patient care.
The full Summary of Revisions is available on cap.org.
About the College of American Pathologists
As the world’s largest organization of board-certified pathologists and leading provider of laboratory accreditation and proficiency testing programs, the College of American Pathologists (CAP) serves patients, pathologists, and the public by fostering and advocating excellence in the practice of pathology and laboratory medicine worldwide. For more information, visit the CAP Newsroom, CAP.org, and yourpathologist.org to watch pathologists at work and see the stories of the patients who trust them with their care.