Paraneoplastic cerebellar degeneration as the first evidence of cancer: a case report.

Paraneoplastic cerebellar degeneration (PCD) is the most frequently seen paraneoplastic syndrome affecting the brain. PCD is most commonly associated with cancers of the ovary, breast, and lung. The anti-Purkinje cell antibodies (anti-Yo) that specifically damage the Purkinje cells of the cerebellum are found in the patient's serum and cerebrospinal fluid. The typical presentation of PCD includes limb and truncal ataxia, often along with dysarthria. This report describes the case of a 47-year-old woman without significant medical history who developed new onset of unsteady gait, headache, and vertigo. The imaging studies suggested rhombencephalitis. The patient initially responded to corticosteroid treatment. Unfortunately, her gait ataxia worsened and she developed dysarthria, neither of which responded to increasing dosages of corticosteroids. Extensive imaging studies showed no evidence of tumor, but the patient was found to have positive anti-Yo antibodies and elevated cancer antigen 125 (CA-125). Pathology results from exploratory laparotomy revealed stage III C adenocarcinoma of the ovary. This case demonstrates that PCD may be the presenting symptom of an occult malignancy. The pathogenesis, diagnosis, and treatment of PCD, and its rehabilitation implications, are reviewed.