Test Code PC1TC Purkinje Cell Cytoplasmic Antibody Type 1 (PCA-1) Titer, Spinal Fluid
Ordering Guidance
Serum is preferred. Spinal fluid testing is particularly useful when interfering antibodies are present in the serum.
Specimen Required
Only orderable as a reflex. For more information see:
ENC2 / Encephalopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
MDC2 / Movement Disorder, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
MAC1 / Myelopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
Container/Tube: Sterile vial
Specimen Volume: 4 mL
Useful For
Identifying female patients whose subacute cerebellar degeneration or peripheral neuropathy is due to a remote (autoimmune) effect of gynecologic or breast carcinoma
Reporting an end titer result from spinal fluid specimens
Testing Algorithm
If the indirect immunofluorescence pattern suggests Purkinje cell cytoplasmic antibody type 1 (PCA-1), then this test will be performed at an additional charge.
Method Name
Only orderable as a reflex. For more information see:
ENC2 / Encephalopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
MDC2 / Movement Disorder, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
MAC1 / Myelopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
Indirect Immunofluorescence Assay (IFA)
Reporting Name
PCA-1 Titer, CSFSpecimen Type
CSFSpecimen Minimum Volume
1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
CSF | Refrigerated (preferred) | 28 days | |
Frozen | 28 days | ||
Ambient | 72 hours |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Gross icterus | Reject |
Clinical Information
Purkinje cell cytoplasmic autoantibody type 1 (PCA-1), also known as anti-Yo, binds to Purkinje cell cytoplasm in a characteristic pattern by indirect immunofluorescence. It is found in the serum, and usually cerebrospinal fluid, of patients with paraneoplastic cerebellar degeneration associated with gynecological or breast carcinoma. It is also found in some patients with sensory, sensorimotor, or motor neuropathy with some gynecologic cancer. Almost all (99%) seropositive patients are women.
Reference Values
Only orderable as a reflex. For more information see:
ENC2 / Encephalopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
MDC2 / Movement Disorder, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
MAC1 / Myelopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
<1:2
Neuron-restricted patterns of IgG staining that do not fulfill criteria for Purkinje cell cytoplasmic antibody type 1 may be reported as "unclassified antineuronal IgG." Complex patterns that include nonneuronal elements may be reported as "uninterpretable."
Interpretation
Purkinje cell cytoplasmic autoantibody type 1 (PCA-1) has not been found in any healthy subject. It is rarely found in patients with neurologic diseases (including cerebellar disorders) without gynecologic or breast cancer. The ovarian cancers found in these patients are typically limited in metastatic spread and may not be detected by imaging procedures. If mammography is negative, exploratory laparotomy is advised (as a "second look" in management of ovarian carcinoma). Breast carcinoma may coexist with a Mullerian cancer. PCA-1 is rarely found in patients with gynecologic cancer without neurologic dysfunction (<2%). PCA-1 is readily distinguished from PCA-Tr (a marker of Hodgkin lymphoma) and PCA-2 (a marker of small-cell lung carcinoma) by standardized staining criteria. PCA-1 rarely, if ever, has accompanying neuronal cytoplasmic or nuclear antibodies.
Cautions
Purkinje cell cytoplasmic antibody type 1 (PCA-1) is rarely found in male patients (1%, usually with intra-abdominal adenocarcinoma) and never in patients with cerebellar ataxia associated with lung cancer.
Seven different IgG autoantibodies are currently recognized as accompaniments of paraneoplastic neurologic disorders occurring with small-cell lung carcinoma (SCLC):
-Antineuronal nuclear antibody-type 1 (ANNA-1, sometimes called anti-Hu) is found most often with sensory, autonomic, and sensorimotor neuropathies, and encephalomyeloradiculopathies in the context of SCLC
-ANNA-2 (sometimes called anti-Ri) is found most often with midbrain/brainstem encephalitis, cerebellar ataxia, myelopathy associated with breast cancer, or SCLC; peripheral neuropathy may be a presenting sign
-ANNA-3 is found with multifocal autoimmune neurologic manifestations of aerodigestive carcinomas (usually SCLC)
-PCA-2 is found with multifocal autoimmune neurologic manifestations of SCLC
-PCA-Tr is found in patients with cerebellar ataxia related to Hodgkin lymphoma
-Collapsin response-mediator protein-5 neuronal (CRMP-5-IgG) is found in patients with multifocal autoimmune neurologic manifestations of SCLC or neuromuscular or encephalopathic manifestations of thymoma
-Antiglial neuronal antibody (AGNA-1) is found in patients with multifocal autoimmune neurologic manifestations of SCLC, but particularly with Lambert-Eaton syndrome, peripheral neuropathy, limbic encephalitis, and dysautonomia
Method Description
The patient's sample is tested by a standardized immunofluorescence assay that uses a composite frozen section of mouse cerebellum, kidney, and gut tissues. After incubation with sample and washing, fluorescein-conjugated goat-antihuman IgG is applied. Neuron-specific autoantibodies are identified by their characteristic fluorescence staining patterns. Samples that are scored positive for any neuronal nuclear or cytoplasmic autoantibody are titrated to an endpoint. Interference by coexisting non-neuron-specific autoantibodies can usually be eliminated by serologic absorption.(Honorat JA, Komorowski L, Josephs KA, et al: IgLON5 antibody: neurological accompaniments and outcomes in 20 patients. Neurol Neuroimmunol Neuroinflamm 2017 Jul 18;4(5):e385. doi: 10.1212/NXI.0000000000000385)
Day(s) Performed
Monday through Sunday
Report Available
6 to 8 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
86256
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
PC1TC | PCA-1 Titer, CSF | 94363-9 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
43446 | PCA-1 Titer, CSF | 94363-9 |