Glomerular electron-dense deposits and circulating immune complexes in patients with malignant tumours

39 patients with malignant neoplasms were studied for the presence of paraneoplastic glomerular disease. The nephrotic syndrome was found in none of the patients. From 24 patients an adequate renal biopsy specimen was available for examination by electron microscopy. Glomerular electron-dense deposits were found in the biopsies of 11 patients, and in four of them the deposits were subepithelial. Circulating soluble immune complexes were detected in the sera of 14 patients. Deposits and circulating immune complexes occurred simultaneously with a highly significant correlation. Cell-mediated immunity was studied using skin tests to tuberculin and dinitrochlorobenzene (DNCB). Negative tests were seen mainly in patients with circulating immune complexes and/or glomerular deposits. Median survival time in patients with deposits or circulating complexes tended to be shorter than in those without.