prostate-specific antigen (psa) density and free to total psa ratio in diagnosing prostate cancer with prostate-specific anti¬gen levels of 4.0 ng/ml or less

background: we aimed to value the usefulness of free to total prostate-specific antigen and prostate-specific antigen (psa) density for prostate cancer in the patients with psa levels of 4.0 ng/ml or less. methods: a total of 343 subjects with psa levels of 4.0 ng/ml or less were biopsied. all patients were divided into four groups according to the psa levels: 0 to 1.0 ng/ml, 1.1 to 2.0 ng/ml, 2.1 to 3.0 ng/ml, and 3.1 to 4.0 ng/ml. the reliability of cancer detection in relation to the f/t psa ratio and psad were estimated. results: overall, 65 people were diagnosed with prostate cancer. the detection rate was 16.28%、17.17%, 21.82%, 25.00% in subjects with psa levels of 0 to 1.0 ng/ml, 1.1 to 2.0 ng/ml, 2.1 to 3.0 ng/ml, and 3.1 to 4.0 ng/ml, respectively. the f/t psa ratio was significantly lower in patients with prostate cancer and psa levels of 2.1 to 4.0 ng/ml ( p ＜ 0.05). the psad had no statistical significance between the two groups. conclusions: routine prostate biopsy should be undertaken if the f/t psa ratio less than 15% with /without abnormal dre/trus findings.