Delayed Neurological Paraneoplastic Syndrome from a Breast Carcinoma: A Case Report

Abstract

Paraneoplastic neurological syndromes are a group of rare disorders triggered by an abnormal immune system response to a cancerous tumour. A woman with a breast carcinoma underwent neoadjuvant chemotherapy. This was followed by surgery, radiotherapy and endocrine therapy. Her co-morbidities were hypertension and diabetes mellitus. Eighteen months later, she presented with an acute onset of back pain with bilateral lower limb paraparesis. She had fever for 2 weeks prior to this. She was unable to walk and was confined to a wheelchair. She was anaemic with a haemoglobin of 7.3 g%. Spinal magnetic resonance imaging could not find any metastases. Cerebrospinal fluid analysis showed mild pleocytosis and absence of infection and malignancy. Whole body positron emission tomography computed tomography scan did not find any increased metabolic activity. Nerve conduction study showed electrophysiological evidence of generalised sensorimotor axonal polyneuropathy and bilateral subacute-chronic lumbosacral plexopathy. A paraneoplastic antigen autoimmune profile showed that the anti-amphiphysin was at borderline level. She was diagnosed to have neurological paraneoplastic syndrome and given intravenous methylprednisolone and immunoglobulin. Her lower limb weakness gradually improved. This case highlights the importance of recognising paraneoplastic markers like anti-amphiphysin in patients with breast cancer presenting with atypical, symmetric proximal weakness.