Lung cancer with nephrotic syndrome as a paraneoplastic syndrome: A case report.

Paraneoplastic syndromes are immune disorders associated with clinical signs and symptoms caused by substances produced by malignant diseases and are not directly associated with a primary or metastatic tumour. The symptoms are the effects of hormones, immune cross-reactivity or cytokines. Paraneoplastic nephrotic syndrome (PNS) is often associated with membranous nephropathy (MN) in elderly patients with solid tumours, and there is continued debate regarding whether corticosteroids or immunosuppressants should be combined with cancer therapy for the syndrome. The present report describes a male patient with lung cancer associated with secondary MN who achieved remission under radiotherapy, with no use of corticosteroids or immunosuppressants. This case is rare. Therefore, when treating PNS related to lung cancer, more attention should be paid to the treatment of the cancer.