Measurement of serum zinc improves prostate cancer detection efficiency in patients with PSA levels between 4 ng/mL and 10 ng/mL

Aim: To investigate whether the measurement of serum zinc may improve the detection of prostate cancer (PCa) in men who had total prostate-specific antigen (PSA) levels higher than 4.1 ng/mL. Methods: A mass screening for PCa of 3940 men over 50 years old was undertaken using total serum PSA. Of the 190 men (4.8 %) with elevated PSA, 143 (3.6 %) underwent a transrectal ultrasonography (TRUS)-guided biopsy of the prostate, and 42 men (I % of total and 29.3 % of men undergoing biopsy) were found to have cancer. The areas under the receiver operating characteristic curves (ROC-AUC were used to compare the diagnostic power of cancer detection by means of serum zinc, and free PSA/total PSA ratio (f/t). Results: The men with levels of serum zinc that ranged from 40 ng/mL-60 ng/mL, had an age-adjusted odds ratios(OR) of 5.0. A cutoff value of 100 mu g/mL for-serum zinc concentration provided a sensitivity of 90.5 % and a specificity of 32.7 % in elevated PSA range, and a sensitivity of 93.3 % and specificity of 27.1 % in gray zone, respectively. In the gray zone ranges of 4.1 ng/mL-10.0 ng/mL, the ROC-AUC for zinc was 73.0 % higher than 62.7 % of f/t PSA ratio and 56.7 % of total PSA. Conclusion: PCa displays a lower serum zinc concentration. The measurement of zinc levels improves PCa detection in the gray zone compared with the f/t PSA ratio and total PSA.