To compare four cases of paraneoplastic cerebellar ataxia (PCA) associated with three different antibodies (Anti-Yo, Anti-Tr, Anti-VGCC) to assess distinguishing factors in clinical presentation and diagnosis.

Efficient diagnosis of PCA is crucial for effective treatment of cerebellar symptoms and for the potential to reveal an underlying malignancy at an early stage. Currently, several antibodies are implicated in association with PCA. However, there is limited research directly comparing clinical presentations and diagnostic features of Anti-Yo, Anti-Tr, and Anti-VGCC.

Case series.

The case series comprised four patients diagnosed with PCA. One patient (49-yo F) had a history of Cowden syndrome and multiple malignancies, while the other three (ages 67 to 68-yo, 2 F, 1 M) did not have a prior cancer history. Neurologic complaints were similar amongst cases and included vertigo, gait instability, diplopia, dysarthria and dysphagia. The time course of symptom development varied from acute in the patient with anti-Tr to subacute/chronic in patients with anti-Yo and anti-VGCC. Symptoms also varied from mild (Anti-Yo, Anti-VGCC) to severe (Anti-Tr, Anti-VGCC) at the time of presentation. Cerebrospinal fluid (CSF) analysis demonstrated a mild lymphocytic pleocytosis in two patients presenting within one month of symptom onset (Anti-VGCC, Anti-Tr). CSF was critical for the diagnosis of the patient with anti-Tr, while the remaining patients were diagnosed based on serum antibody studies. Both anti-VGCC cases were notably negative for CSF oligoclonal bands.

Though PCAs share common clinical symptoms, presentations can vary by time course and symptom severity. The heterogeneity in clinical presentation based on antibody contributes to uncertainty and delays in diagnosis, treatment, and recognition of underlying malignancy.  This case series highlights unique clinical features and diagnostic considerations of patients with anti-Yo, anti-VGCC, and anti-Tr PCA that may allow for earlier identification and diagnosis of this complex condition.