Membranoproliferative glomerulonephritis associated with small cell lung carcinoma.

An association between nephropathy and malignant solid tumours or with lymphoproliferative disorders was repeatedly reported. This association is mainly manifested by a nephrotic syndrome. In Lee's study [14], 11% of the adult nephrotics whom they had seen over a ten-year period developed a carcinoma. Membranous glomerulonephritis (MGN) is the most common glomerular disease associated with malignant solid tumour; the association of membranoproliferative glomerulonephritis (MPGN) with solid tumour is still uncommon. Although lung carcinoma is relatively common, the incidence of glomerular involvement with this tumour is quite rare. To date, only a few cases of lung cancer associated with nephrotic syndrome or glomerulonephritis have been reported by various authors. MGN is the most common glomerular lesion associated with these cases; however, MPGN has not been reported to be associated with lung cancer before. We report on a 45-year old man with nephrotic syndrome due to MPGN which in this case seemed to be a component of the paraneoplastic syndrome.