Purkinje Cell Cyto Ab Type Tr

Purkinje Cell Cytoplasmic Antibody Type Tr (PCA-Tr)

What is PCA-Tr?

Purkinje Cell Cytoplasmic Antibody Type Tr (PCA-Tr) is an autoantibody—a type of protein made by your immune system that mistakenly targets your own tissues. Specifically, PCA-Tr targets Purkinje cells, which are specialized neurons found in the cerebellum, the part of the brain that helps control coordination and balance.

This antibody is classified as a paraneoplastic antibody, meaning it is often produced as a response to an underlying cancer. The immune system, while trying to fight the cancer, may also attack healthy brain tissue—leading to neurological symptoms.

What does a positive PCA-Tr result mean?

A positive PCA-Tr test is a strong indicator of a paraneoplastic neurological syndrome (PNS)—a rare group of disorders that occur when cancer-fighting antibodies mistakenly damage parts of the nervous system.

PCA-Tr is most commonly associated with:

• Hodgkin lymphoma, a type of blood cancer

In many cases, PCA-Tr is linked to a condition called paraneoplastic cerebellar degeneration (PCD), where the cerebellum becomes inflamed and damaged, leading to symptoms like:

• Unsteady gait or trouble walking

• Dizziness or vertigo

• Slurred speech

• Coordination problems

• Double vision or abnormal eye movements

Why is this test important?

If you're experiencing unexplained balance issues or neurological symptoms—and especially if there's suspicion of an underlying cancer—testing for PCA-Tr can help identify whether your immune system is involved. A positive result often prompts doctors to search for an occult (hidden) cancer, particularly Hodgkin lymphoma.

Early detection can lead to quicker treatment of both the neurological symptoms and any associated cancer.

Does a negative result rule out all problems?

No. A negative PCA-Tr result does not rule out all paraneoplastic or autoimmune neurological conditions. If symptoms persist, your doctor may recommend testing for other antibodies or ordering brain imaging.

Summary

• PCA-Tr is an autoantibody linked to brain inflammation caused by the immune response to cancer.

• It is most often associated with Hodgkin lymphoma and paraneoplastic cerebellar degeneration.

• A positive result can guide doctors toward further testing for underlying cancer and immune-based treatments.

Always consult your healthcare provider for interpretation of test results and next steps tailored to your specific condition.