Paraneoplastic Ab
Performed by: LabCorp
Paraneoplastic Antibodies (Paraneoplastic Ab)
What Are Paraneoplastic Antibodies?
Paraneoplastic antibodies are a group of autoantibodies produced by the immune system in response to certain types of cancer (neoplasms). Instead of only attacking cancer cells, these antibodies may mistakenly target healthy nerve or brain tissue, leading to a set of conditions known as paraneoplastic neurological syndromes (PNS).
These antibodies serve as biomarkers—helping doctors detect the presence of an underlying tumor and explaining unexplained neurological symptoms.
Why Are These Antibodies Important?
Paraneoplastic antibodies can help:
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Identify a hidden (occult) cancer before it causes obvious symptoms
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Explain neurological symptoms that do not have a clear cause
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Support a diagnosis of autoimmune encephalitis, neuropathy, cerebellar degeneration, or myelopathy
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Guide cancer screening and neurologic workup
Common Paraneoplastic Antibodies Include:
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Anti-Hu (ANNA-1) – often linked to small cell lung cancer
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Anti-Yo (PCA-1) – associated with breast or gynecologic cancers
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Anti-Ri (ANNA-2) – seen in breast and lung cancer
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CRMP5 (CV2), Ma2, Amphiphysin, and others
Each antibody is associated with specific cancer types and neurological symptoms, and their detection helps narrow down the underlying cause.
Who Should Be Tested?
Your doctor may order a paraneoplastic antibody panel if you experience:
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Sudden or unexplained neurological symptoms (memory loss, seizures, balance problems)
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Progressive weakness or numbness
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Autoimmune encephalitis
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Neurological symptoms with a history or suspicion of cancer
What Does a Positive Result Mean?
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A positive result suggests that your symptoms may be related to an autoimmune response to an underlying cancer.
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It does not confirm cancer, but it raises the suspicion and typically prompts additional testing (e.g., imaging, oncology referral).
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Some people with a positive result may not have cancer but still experience autoimmune neurologic symptoms.
What Does a Negative Result Mean?
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A negative result means no known paraneoplastic antibodies were detected.
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However, this does not rule out all autoimmune conditions. If symptoms persist, more targeted antibody testing may be needed based on your clinical presentation.
Summary
The Paraneoplastic Antibodies category includes important tests that can help uncover hidden cancers and explain neurological symptoms caused by autoimmune reactions. These markers play a critical role in early diagnosis, guiding treatment, and improving outcomes for individuals with paraneoplastic neurological syndromes.
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Biomarkers included in this panel:
The AQP4 Antibody (Cell-based IFA) test detects autoantibodies directed against aquaporin-4, a water channel protein located on astrocytes in the central nervous system. When present, these antibodies cause inflammation and damage, leading to neurom
Learn moreThe DPPX antibody test checks for autoantibodies against DPPX (DPP6), a neuronal cell-surface protein that helps regulate brain and nerve excitability. When present, these antibodies are linked to autoimmune DPPX encephalitis, a potentially treatable
Learn moreWhat is the VGCC Antibody? The VGCC (Voltage-Gated Calcium Channel) antibody is an autoantibody that targets calcium channels found on the surface of nerve cells. These channels play a critical role in transmitting nerve signals, especially in mus
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