Urinary albumin excretion and transcapillary escape rate of albumin in malignancies

Transcapillary escape rate of albumin was determined in 22 patients with di fferent malignancies, In addition, urinary albumin excretion rate was measu red in 24-h urine samples using a sensitive immunoassay, Increased urinary albumin excretion was defined as greater than or equal to 20 mu g/min accor ding to conventional standards, Renal glomerular filtration and tubular fun ction was estimated by Cr-51-EDTA plasma clearance and urinary beta 2-micro globulin, respectively, Median urinary albumin excretion rate was 15.0 mu g /min (range 6-510 mu g/min) and the frequency of increased urinary albumin excretion was 41%, This agrees with other studies showing increased albumin uria in several types of malignant diseases, Patients with advanced disease (tumour, node, metastasis (TNM) stage II-IV) had a significantly higher ur inary albumin excretion rate than patients with localized disease (TNM stag e I), Serum creatinine, glomerular filtration rate and urinary beta 5-micro globulin were all within normal limits, Median transcapillary escape rate o f albumin was 5.5 %/h (range 2-8 %/h) and this level is comparable with val ues in healthy subjects, There was no significant difference in transcapill ary escape rate between patients with elevated urinary albumin excretion an d the normoalbuminuric group, Median value of the absolut outflux of albumi n was 10.6 g/h with similar levels in patients with increased urinary album in excretion and patients with normoalbuminuria. Our results indicate a hig h prevalence of minor glomerular dysfunction with a slightly elevated urina ry albumin excretion in patients with malignancies, The normal endothelial function, as estimated by the transcapillary escape rate of albumin, sugges ts an overall unaffected capillary permeability and increased urinary album in loss appears to be an isolated renal phenomenon in cancer patients.