A Rare Case of Paraneoplastic Encephalitis in Association With Breast Cancer

Abstract

We present a case of a 47-year-old female who presented with diffuse dysesthetic pain in both legs for past 3 months. She described the sensation as of pins and needles. She also had balance difficulty and developed progressively worsening back pain and spasms. Relatives reported that the patient had memory difficulties. The patient would repeat questions even after the questions had already been answered. Magnetic resonance imaging (MRI) of cervical, thoracic and lumbosacral spine with and without contrast showed mild multilevel degenerative changes in cervical spine and minimal disc bulges from L1 to S1 levels with no areas of significant spinal canal or neural foraminal stenosis. MRI of brain was performed which showed abnormal T2/FLAIR hyperintensity along the left medial temporal lobe and additional small foci in the right centrum semiovale/corona radiate and bilateral periventricular white matter. Based on the MRI findings, a diagnosis of limbic encephalitis was made. A lumbar puncture was also done. Cerebrospinal fluid (CSF) showed 14 oligoclonal bands with elevated IgG synthesis. Paraneoplastic antibody panel showed high titers of amphiphysin antibody (1:15,360). Since this is a paraneoplastic antibody, computed tomography of chest, abdomen and pelvis was performed. It showed several enlarged right axillary lymph nodes. Ultrasound of right breast showed 4 mm hypoechoic nodule at 2 o’clock axis (upper inner quadrant). The biopsy of this lesion and axillary lymph node showed invasive ductal carcinoma of the breast. For further evaluation, MRI of bilateral breast was performed. It revealed additional areas of enhancements in upper outer and lower outer quadrants of right breast. Biopsy of the upper outer area of enhancement revealed invasive ductal carcinoma and ductal carcinoma in situ (DCIS). Biopsy of the lower outer aspect showed infiltrating lobular carcinoma and lobular carcinoma in situ (LCIS). Our report highlights a rare patient presenting with paraneoplastic limbic encephalitis with underlying breast cancer. When encountering a patient with unexplained neurologic symptoms, paraneoplastic neurological syndromes (PNSs) should be considered as part of the differential. And a thorough search of autoantibodies associated with PNS should be considered. If such autoantibodies are present, search for an underlying malignancy should be undertaken. J Med Cases. 2018;9(9):296-302 doi: https://doi.org/10.14740/jmc3120w