Serum total sialic acid and cathepsin-D increase the accuracy of free-to-total PSA ratio in diagnosis of BPH and prostate cancer

ABSTRACT

To evaluate the combination of free-to-total PSA ratio, serum total sialic acid and serum cathepsin-D in differentiation of patients with benign prostatic hyperplasia from those with prostate cancer. From June 2004 to June 2007, sixty eight patients with ages ranging from 51 to 80 years, and a control group of 25 healthy males volunteers were included in this study. Blood samples were obtained from every patient and control by venipancture before any manipulation of the prostate to assay total PSA [t/PSA], free PSA [f/PSA], total sialic acid [TSA] and cathepsin-D. All patients had serum total PSA less than 20 ng/ml. TRUS examination of the prostate and TRUS guided biopsy were done to all patients. The patients were classified in two groups, the first group included 38 patients, with histopathologically proved BPH. The second group included 30 patients with organ confined or locally advanced prostate cancer. Mean serum level of total sialic acid and mean serum cathepsin-D were significantly elevated in patients with prostate cancer compared with those of controls and patients with benign prostatic hyperplasia. Patients with prostate cancer showed statistically significant lower free-to-total PSA ratio in comparison to those of benign prostatic hyperplasia. The combined measurement of free-to-total PSA ratio with total sialic acid and serum cathepsin-D elevate the efficacy of free-to total PSA ratio in differentiation between benign prostatic hyperplasia and prostate cancer