Thyroglobulin, Tumor Marker, Fine-Needle Aspiration Biopsy Needle Wash
Use
This test is utilized for confirming or excluding metastases in enlarged or ultrasonographically suspicious lymph nodes from athyrotic individuals treated for differentiated thyroid cancer, in conjunction with cytologic analysis. It is also used for confirming or excluding the presence of thyroid tissue in the biopsied area of athyrotic individuals treated for differentiated thyroid cancer. However, it is not suitable for screening asymptomatic individuals for neoplastic disease. The test measures thyroglobulin in FNAB needle washes, which enhances the evaluation of suspicious lymph nodes in athyrotic patients suspected of metastatic differentiated follicular cell-derived thyroid carcinoma, especially when cytology results are non-diagnostic or indeterminate.
Special Instructions
The biopsied site must be identified as from a lymph node or non-lymph node source, and the specific biopsy site must be clearly identified. Needle wash specimens should be collected in conjunction with cytology specimens. Saline is the only acceptable solution for needle washings. Inspect the specimen for visible blood or tissue contamination as necessary.
Limitations
The test is validated only in single lymph nodes from athyrotic patients. FNAB thyroglobulin levels should not be interpreted as absolute evidence of the presence or absence of malignant disease and should be used alongside other clinical tools. Immunometric assays may occasionally be subject to interferences such as 'hooking' at very high analyte concentrations and autoantibody interference, which could lead to false results. The test results should be interpreted in the context of serum thyroglobulin concentrations, and blood-contaminated samples should be noted.
New York Approved
Methodology
Immunoassay (Immunoenzymatic Assay)
Biomarkers
LOINC Codes
- 53922-1
- 53920-5
- 53922-1
- 69053-7
- 31208-2
- 39111-0
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Other
Volume
1 to 1.5 mL
Minimum Volume
0.5 mL
Container
Plain, plastic, screw-top tube
Collection Instructions
Needle wash specimens for analysis should be collected in conjunction with cytology specimens. Saline is the only acceptable solution. After each FNAB, withdraw saline through the needle and expel it into a plastic tube.
Patient Preparation
For 12 hours before specimen collection, patient should not take multivitamins or dietary supplements containing biotin.
Causes for Rejection
Gross hemolysis
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 7 days |
| Refrigerated | 14 days |
| Frozen | 90 days |