Significance of Serum Concentration of Free and Total Prostate Specific Antigen in Benign Prostatic Hyperplasia and Prostate Cancer / 대한비뇨기과학회지

PURPOSE: This study was performed to investigate whether the free to total PSA ratio(F/T PSA ratio) offers a better discriminant for the detection of patient with prostatic cancer(CaP) and those with benign prostatic hyperplasia(BPH) than serum total PSA alone. MATERIALS AND METHODS: From September 1996 to February 1999, free and total PSA levels were measured on frozen sera samples of 154 men with BPH and 46 with CaP using immunoradiometric assay. RESULTS: In all subjects, the mean total PSA was significantly higher in CaP group(72.59+/-66.58ng/ml) than BPH group(3.12+/-4.10ng/ml). The mean PSAD was significantly higher in CaP group(1.64+/-1.86) than BPH group(0.08+/-0.01). The mean F/T PSA ratio was significantly lower in CaP group(0.19+/-0.07) than BPH group(0.30+/-0.13). Among 41 subjects whose total PSA were between 4-20ng/ml, the mean PSAD was significantly higher in CaP group(0.37+/-0.16) than BPH group(0.17+/-0.07), but the mean F/T PSA ratio was not significantly different between CaP(0.19+/-0.10) and BPH group(0.25+/-0.13). By comparing the sensitivity and specificity of total PSA alone, PSAD and F/T PSA ratio on receiver operating characteristic(ROC) curve in all subjects and subjects with total PSA between 4-20ng/ml, F/T PSA ratio had no superiority than total PSA alone and PSAD for. discrimination between CaP and BPH. CONCLUSIONS: We suggest that the F/T PSA ratio is not superior to total PSA alone and PSAD in the detection of prostatic cancer, and further evaluation of the usefulness of F/T PSA ratio should be required.

The Value of Free/Total Prostate Specific Antigen Ratio in the Diagnosis of Prostate Cancer / 대한비뇨기과학회지

PURPOSE: We investigated the value of the free to total PSA ratio of intermediate serum PSA levels(4-20ng/m1) in the detection of prostate cancer. MATERIALS AND METHODS: Free PSA, total PSA levels and free to total PSA ratio(F/T ratio) were measured on sera samples of 103 men with symptomatic BPH and 20 men with prostate cancer, who were proved by biopsy, by using ELSA-PSA2 and FPSA-RIACT. And we used transrectal ultrasound determined prostate volume to calculated PSA density(PSAD). RESULTS: In all patients, mean PSAD was significantly greater for patients with cancer(2.07+/- 1.65) versus BPH(0.120.12). The F/T ratio was significantly lower for cancer(0.12+/-0.04) compared with BPH(0.32+/-0.20). At a time, when serum PSA between 4 and 20ng/m1 was considered in 8 patients with cancer and 38 patients with BPH, mean total serum PSA was significantly greater for patients with cancer(12.02+/- 3.54ng/m1) versus BPH(7.21 +/-3.68ng/m1). Mean PSAD was significantly greater for patients with cancer(0.36+/- 0.12) versus BPH(0.20+/-0.12) and the F/T ratio was significantly lower for cancer(0.14+/-0.03) compared with BPH(0.25+/-0.12). Use of the Ff ratio of 0.15 resulted in the highest sensitivity(75%) and specificity(89.5%) and the F/T ratio was superior to total PSA when compared with receiver operating characteristic curve . CONCLUSIONS: The F/T ratio give a significant improvement over total PSA value in the diagnosis of prostate cancer in patients with intermediate PSA levels. But, to assess accurately usefullness of F/T ratio in early prostate cancer detection, further studies are needed and consensual threshold value is necessary.