Breast Cancer Biomarkers (ER, PR, HER2, Ki-67) - Reagents & Materials

Official basis (Guidance): CDC 2026 testing guidance recognizes DFA and IHC. Human antemortem diagnosis requires multiple specimen types and tests; a single negative stain is insufficient.

Procurement note: Guidance supports method families, not interchangeable components. Laboratory specifies compatibility; no live stocks or preparation procedure.

Sources:G016 CDC

Official basis (Guidance): CAP 2024 specifies analytic validation principles. Apply biomarker specific scoring and assay instructions; HER2, ER, PR and PD L1 cannot share a universal positivity rule.

Procurement note: DAB commonly permits resin; AEC/Fast Red need compatible aqueous systems unless formulation states otherwise. Individual antibody/platform IFU governs.

Sources:G032 College of American PathologistsG033 ASCO and College of American Pathologists

Official basis (Guidance): Use disease and probe specific interpretation. ASCO/CAP HER2 guidance applies to HER2 breast testing; it does not govern unrelated rearrangements.

Procurement note: Select probe design/specimen explicitly. HER2 guidance does not validate all rearrangement probes.

Sources:G033 ASCO and College of American Pathologists