Objective:

We present an 81-year-old woman of atypical paraneoplastic syndrome that initially manifested as autoimmune encephalitis with seizures and speech disturbances. Her encephalitis was later complicated with progressive axonal sensorimotor polyneuropathy and anemia of chronic inflammation. Paraneoplastic panel showed strong anti-Yo antibody positive. Repeated cancer investigations revealed stage IIIc endometrial cancer.

Background:

Paraneoplastic syndromes are rare immune responses to solid tumors. The typical presentation of anti-Yo antibodies is cerebellar degeneration, which is more commonly associated with ovarian and breast cancers. In the literature, anti-Yo antibodies have been reported in endometrial cancers, lung cancers, and Hodgkin’s disease. Management is to treat the underlying malignancy. However, neurologic paraneoplastic symptoms usually develop before the underlying cancer is identified. Identifying atypical paraneoplastic syndrome and investigating its underlying malignancy are paramount in patients with rare presentations.

Design/Methods:

Case report

Results:

An 81-year-old woman who was initially independent in daily activities without a history of malignancy presented to the emergency department due to acute-onset disorientation, speech disturbance, and bizarre behavior following weeks of poor oral intake and progressive general weakness. She was diagnosed with autoimmune encephalitis and received high-dose steroids and six sessions of plasmapheresis. Her speech disturbance only partially improved, with subsequent worsening weakness. A survey during the next admission revealed anemia of chronic disease and worsening severe axonal sensorimotor polyneuropathy. No known malignancy was found. However, paraneoplastic panel showed strong positive for anti-Yo antibodies (+++). Repeated cancer investigation revealed endometrial carcinoma, clinical stage IIIc.

Conclusions:

Neurologic paraneoplastic syndrome is believed to be immune-mediated and may be partially improved by immunosuppressants. Despite the current understanding of well-characterized paraneoplastic syndromes, there are rarer and atypical presentations that are also paraneoplastic in etiology. Lesions that affect multiple levels of the nervous system (e.g., encephalomyeloradiculitis) in older patients should raise more suspicion of paraneoplastic pathology and channel efforts in surveys for occult malignancy.