PMID- 9284198
OWN - NLM
STAT- MEDLINE
DCOM- 19970922
LR  - 20190719
IS  - 0007-1331 (Print)
IS  - 0007-1331 (Linking)
VI  - 80
IP  - 2
DP  - 1997 Aug
TI  - Serum free prostate-specific antigen in the diagnosis of prostate cancer.
PG  - 256-9
AB  - OBJECTIVE: To determine the value of the ratio of free prostate-specific antigen 
      (fPSA) to total PSA (tPSA) in the diagnosis of benign prostatic hyperplasia (BPH) 
      and prostate cancer in a cohort of patients undergoing prostatic transrectal 
      ultrasonography (TRUS). PATIENTS AND METHODS: The study comprised 153 patients 
      (99 with BPH and 54 with prostate cancer) undergoing diagnostic TRUS of the 
      prostate. Patients with a tPSA of > 30 ng/mL were excluded from analysis. Free 
      PSA was assayed using an immunoassay specific for unbound PSA (CanAg Diagnostics, 
      Sweden). Total PSA was measured using the HybriTech Tandem-R PSA 
      immunoradiometric assay in routine clinical use and this estimate was validated 
      using the CanAg tPSA assay. RESULTS: The measurements of tPSA from both assay 
      systems correlated closely. The f/tPSA ratios in patients with prostate cancer 
      were significantly lower than in those with BPH (median values 0.152 and 0.2, 
      respectively, P<0.01). In patients with prostate cancer, the median f/t PSA 
      levels apparently declined with increasing tPSA levels but in those with BPH, the 
      levels of tPSA were not significantly associated with the f/tPSA ratio; the 
      ratios did not vary significantly with age in either group. A f/tPSA ratio at a 
      threshold of 0.16 had positive and negative predictive values of 44% and 74%, 
      respectively; the corresponding values for a tPSA of > 4 ng/mL were 30% and 52%. 
      CONCLUSION: The f/tPSA ratio differs significantly between patients with BPH and 
      cancer but because there is a considerable overlap of f/tPSA ratios between the 
      groups, f/tPSA values alone were not sufficiently specific to be used as a single 
      diagnostic test.
FAU - Leung, H Y
AU  - Leung HY
AD  - University Urology Unit, Freeman Hospital, Newcastle upon Tyne, UK.
FAU - Lai, L C
AU  - Lai LC
FAU - Day, J
AU  - Day J
FAU - Thomson, J
AU  - Thomson J
FAU - Neal, D E
AU  - Neal DE
FAU - Hamdy, F C
AU  - Hamdy FC
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Br J Urol
JT  - British journal of urology
JID - 15740090R
RN  - 0 (Neoplasm Proteins)
RN  - EC 3.4.21.77 (Prostate-Specific Antigen)
SB  - IM
MH  - Biopsy
MH  - Cohort Studies
MH  - Humans
MH  - Male
MH  - Neoplasm Proteins/*blood
MH  - Predictive Value of Tests
MH  - Prospective Studies
MH  - Prostate-Specific Antigen/*blood
MH  - Prostatic Hyperplasia/blood/*diagnosis
MH  - Prostatic Neoplasms/blood/*diagnosis
MH  - Sensitivity and Specificity
MH  - Ultrasonography, Interventional
EDAT- 1997/08/01 00:00
MHDA- 1997/08/01 00:01
CRDT- 1997/08/01 00:00
PHST- 1997/08/01 00:00 [pubmed]
PHST- 1997/08/01 00:01 [medline]
PHST- 1997/08/01 00:00 [entrez]
AID - 10.1046/j.1464-410x.1997.00230.x [doi]
PST - ppublish
SO  - Br J Urol. 1997 Aug;80(2):256-9. doi: 10.1046/j.1464-410x.1997.00230.x.