What happened, in summary

A 67-year-old woman with diabetes, hypertension and a smoking history first sought care for marked weight loss, fatigue, nausea and vomiting. Within the following month, she developed poor coordination, repeated falls, tingling and severe neuropathic pain in both legs. The sensory loss and loss of position awareness progressed rapidly until she could no longer stand or walk. Imaging and laboratory studies excluded several metabolic, spinal and autoimmune causes. PET imaging identified a hypermetabolic nodule in the right lung, although initial bronchoscopic samples were negative. Testing found anti-Hu, anti-CV2/CRMP5 and anti-SOX1 antibodies, supporting a severe paraneoplastic sensory and dysautonomic neuropathy. Later biopsy confirmed small-cell lung cancer. Because the neurological decline was rapid, she received high-dose intravenous corticosteroids, intravenous immunoglobulin and immunosuppressive treatment before the cancer diagnosis was secured. The lung cancer was treated with carboplatin and etoposide every 3 weeks. A good CT response after three cycles led to three additional cycles. Neuropathic pain improved somewhat after the second immunoglobulin course, but the ataxia and abnormal sensations continued to spread to her thighs, abdomen and upper limbs. Treatment was complicated by neutropenic urinary infection. She later developed a brain haemorrhage associated with severe thrombocytopenia and became hemiplegic. Palliative care was started, and she died within the following weeks.