Correlation of Serum Free/Total Prostate Specific Antigen Ratio with Histological Features for Differential Diagnosis of Prostate Cancer

摘要

This study sought to find the correlation between Free to TPSA (F/T PSA) ratio and the histological grades of prostate cancer. Among 120 selected from both in-patients and out-patient clinic of the urology unit, 51 underwent tissue biopsies within six months of their PSA measurements using enzyme immunoassay. The F/T PSA ratios of patients with prostate cancer were compared to those with BPH, using the students` t-test. Correlation between histology grades and F/T PSA ratios was calculated by the Pearson test and linear regression. Receiver Operating Characteristic (ROC) curves were generated from sensitivities and specificities of various F/T PSA ratios, FPSA and TPSA levels. The F/T PSA ratio was significantly lower in the group of patients with prostate cancer (PCa) (0.118 ± 0.0043) compared to BPH (0.302 ± 0.0179, p2 = 0.76, p<0.0001), that is, the higher the histology grade, the lower the F/T PSA ratio. The best accuracy was obtained with F/T PSA ratio cut-off at 0.15, with specificity of 87.50% and sensitivity of 100%. The use of the F/T PSA ratio improves PSA-based differential diagnoses of prostate cancer in patients and can also lead to more specific identification of potentially curable prostate cancer and reduce unnecessary prostate biopsies.