Painful neuropathy in a diabetic patient resulting from lung cancer and not diabetes: A case report

The current study reports the case of a 61-year-old man with diabetes who was suffering from generalized pain over the whole body and gradually progressive numbness. The patient was initially diagnosed with diabetic peripheral neuropathy and received treatment, however, the symptoms persisted. In October 2010, the patient was admitted to the Chinese People's Liberation Army Navy General Hospital (Beijing, China) for the treatment of diabetes, however, a full-body sharp pain was also described, which was relieved upon massaging the area. Causes, other than diabetes, were investigated for these symptoms. Chest computed tomography and positron emission tomography-computed tomography scans revealed a mass shadow in the right lower lobe of the lung, with multiple lymphatic metastases. Lung cancer was diagnosed with a tumor-node-metastasis stage of T1N3Mx. Following treatment of the cancer with chemotherapy and radiotherapy, the patient's symptoms were significantly improved. The present study reports a rare case of a paraneoplastic neurological syndrome (PNS) that presented as painful neuropathy resulting from lung cancer, which mimicked diabetic peripheral neuropathy.