Small cell lung cancer with paraneoplastic nephrotic syndrome.

We present a case of nephrotic syndrome, associated with small cell lung carcinoma. Renal biopsy revealed membranous glomerulonephritis, probably due to immune complex deposition with tumour antigen. Complete remission of the small cell lung carcinoma after chemotherapy was followed by regression of the nephrotic syndrome. This regression persisted even when brain metastases developed, without simultaneous relapse of tumour outside the central nervous system.