Cytokeratin AE1/AE3, IHC with Interpretation
Use
This first-line screening immunohistochemical test evaluates neoplasms of unknown origin and assists in determining epithelial cell lineage by detecting cytokeratin AE1/AE3 expression. Positive staining typically appears as filamentous cytoplasmic or membranous reactivity, suggesting epithelial origin. Note that reactivity may be variable in neuroendocrine carcinomas (e.g., small cell carcinoma), while hepatocellular carcinoma and adrenocortical neoplasms often lack reactivity. CK AE1/AE3 does not detect CK9, CK12, CK17, or CK18, and cross-reactivity can occur in select non‑epithelial cells such as glioblastoma. Interpretation should be performed in the clinical and pathological context by a qualified pathologist.
Special Instructions
Interpretation provided as part of the test. Please include the surgical pathology report with the submission. This is an IHC assay; refer to Quest’s standard specimen transport requirements.
Limitations
Variability in reactivity (e.g., neuroendocrine carcinomas may show perinuclear dot pattern), non-reactivity in hepatocellular and adrenocortical tumors, limited detection of CK9, CK12, CK17, CK18, and possible cross-reactivity with non‑epithelial cell types (e.g., glioblastoma). Interpretation requires correlation with pathological and clinical context. Specimen fixation issues (e.g., non‑10% formalin, age of slides) may affect staining quality.
Methodology
Immunoassay (IHC)
Biomarkers
Result Turnaround Time
2 days
Related Documents
For more information, please review the documents below
Specimen
Tissue
Volume
Not provided
Minimum Volume
Not provided
Container
IHC specimen transport kit
Collection Instructions
Formalin‑fixed, paraffin‑embedded tissue block preferred; alternatively, 3 unstained, positively charged slides.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Indefinitely |
| Refrigerated | Indefinitely |
| Frozen | Unacceptable |