Paraneoplastic cerebellar degeneration with bilateral facial palsy: a rare primary presentation of breast cancer.

Paraneoplastic cerebellar degeneration is a rare dysfunction of the cerebellum associated with malignancy. Nevertheless, it is the most common paraneoplastic syndrome affecting the brain. A 50-year-old woman presented to the neurology outpatient department (OPD) with symptoms of cerebellar dysfunction since 4 months and complaints of a painless lump in the right breast and drooling from mouth since 1 month. Examination revealed classical signs of cerebellar dysfunction and a 5×5 cm lump in the right breast with a single right axillary lymph node. Serum anti-Yo antibody titre was strongly positive. The patient was referred to General Surgery OPD for opinion. After establishing the diagnosis of right breast carcinoma; she underwent a right modified radical mastectomy. She was referred to the oncologist for chemo/radiotherapy but because of poor performance status, only symptomatic treatment was pursued. Follow-up till now shows no improvement in the neurological dysfunction.