Objective:

Our objective was to analyze imaging findings in patients with paraneoplastic cerebellar degeneration (PCD). 

Background:

PCD is an autoimmune process that destroys cerebellar Purkinje cells, causing nystagmus, ataxia, and dysarthria. The most common antibodies associated with PCD are PCA1, PCA2, anti-Ma2, anti-Ri, and anti-Tr, but some cases are antibody negative. Most cases of PCD are associated with an underlying malignancy, with breast, ovarian, and small cell lung cancers being most common. The consensus on imaging findings in PCD patients remains unclear, however.  Initial MRI’s in PCD patients are often unremarkable or have non-specific FLAIR changes without enhancement. Over time, cerebellar atrophy is evident on imaging and hypometabolism can be seen on FDG-PET. Some review papers and case reports have cited that MRI in PCD can have leptomeningeal enhancement. Cytology from CSF is somewhat insensitive in definitively diagnosing leptomeningeal metastases. 

Design/Methods:

We analyzed a retrospective database of 26 patients with PCD. We analyzed their MRI's throughout the course of their disease, their antibody status, and their overall prognosis. 

Results:

Of these 26 patients, only 3 had cerebellar enhancement during their disease course and all 3 of these patients had leptomeningeal disease and subsequently died. Two of these patients had positive PCA1, with the other patient having antibody negative disease. 

Conclusions:

Thus, we report that leptomeningeal enhancement in PCD patients should prompt investigations for leptomeningeal metastases.