Purkinje Cell Cytoplasmic Antibody Type 2 (PCA-2) Titer, Serum
Use
This test is useful for evaluating patients who present with a subacute neurological disorder of undetermined etiology and have risk factors for lung cancer. It reports an end titer result from serum specimens. Purkinje cell autoantibodies are recognized markers of immune response to specific cancers, including small-cell lung carcinoma. PCA-2 is associated with neurological autoimmunity and justifies a search for associated malignancies.
Special Instructions
This test is only orderable as a reflex and requires prior identification of an immunofluorescence pattern that suggests PCA-2. It is often performed in conjunction with other paraneoplastic and autoimmune evaluations.
Limitations
PCA-2 positive values at dilutions 1:240 or higher indicate potential neurological autoimmunity, although there is a small (<2%) rate of positive results in patients with uncomplicated small-cell lung carcinoma. Interference by coexisting non-neuron-specific autoantibodies can usually be eliminated by serologic absorption. Western blot with native neuronal proteins may be required to detect a positive result when interfering autoantibodies preclude interpretation.
New York Approved
Methodology
Immunoassay (Indirect Immunofluorescence Assay (IFA))
Biomarkers
LOINC Codes
- 94351-4
- 94351-4
Result Turnaround Time
5-8 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
Not provided
Minimum Volume
0.6 mL
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 28 days |
| Frozen | 28 days |