The relationship between prostate zinc levels and serum levels of prostate specific antigen may be useful in diagnosing prostate cancer.
In the December issue of the Journal of Urology, a multicenter Israeli team led by Dr. David Vartsky at the Weizmann Institute of Science in Rehovot, Israel, explains that in patients with prostate cancer, the ability of the prostate cells to concentrate zinc is impaired. In tissue samples taken from 28 men who underwent surgery for prostate cancer, the researchers determined the zinc concentration using x-ray fluorescence. They found that zinc concentrations varied even in samples taken from the same anatomical region of the prostate, and that “a number of measurements at various locations is necessary for a diagnostic procedure.”They discovered, however, that there is a correlation of zinc levels with histologic data and with serum levels of prostate specific antigen. A combination of PSA and zinc levels “represents a significant improvement on the diagnostic value of each of them separately and provides a powerful tool for more accurate diagnosis,” Dr. Vartsky and colleagues determined. For example, they report, using a lower limit of 4 ng/ml for prostate specific antigen and an upper limit of 80 ?g/g for zinc, the rate of false positive diagnoses is 18%. Without factoring in the zinc level, the false-positive rate would be 47%.The relationship between zinc levels in prostate cells and serum levels of prostate specific antigen “allows improved discrimination between benign prostatic hypertrophy and prostate cancer, and it may represent a powerful tool for more accurate diagnosis,” the investigators conclude. (Source: J Urol 2003;170:2258-2262: Reuters Health: December 31, 2003: Oncollink)