Increased urinary albumin excretion rate in breast cancer patients

Abstract

A high frequency of slightly increased urinary albumin excretion (UAE) has been reported in patients with malignancies. Earlier studies have indicated a prognostic significance of UAE in some malignant diseases. We measured urinary albumin in 24-h urine samples in 44 patients with newly diagnosed early breast cancer and in 22 patients with relapse of metastatic breast cancer disease. The prevalence of microalbuminuria (≥ 20 μg/min) was 20.5% in patients with early breast cancer and 54.5% in patients with metastatic disease. Median UAE was significantly higher in patients with metastatic breast cancer compared with the early breast cancer group (20.5 μg/min vs. 9.2 μg/min; p < 0.01). In patients with metastatic breast cancer, univariate survival analysis revealed a significantly lower survival rate in patients with microalbuminuria compared with the normoalbuminuric group (p <0.001). The present study demonstrates a high frequency of microalbuminuria in patients with breast cancer. Increased UAE was most prevalent in patients with metastatic disease. Our results also suggest that UAE may be a prognostic marker in metastatic breast cancer. Further prospective studies with a larger number of patients and controls are needed to test the validity of these observations.