Free/total PSA ratio can help in the prediction of high gleason score prostate cancer in men with total serum prostate specific antigen (PSA) of 3-10 ng/ml.
OBJECTIVE
We evaluate the use of free/total prostate specific antigen (PSA) ratio in improving the prediction of cancers of higher Gleason scores.


METHODS
A total of 164 patients with total serum PSA of 3.0-10.0 ng/ml underwent extended TRUS-guided core biopsy. In each man serum free PSA was measured and the free/total (F/T) PSA ratio was calculated. Out of the 164 patients who underwent TRUS-biopsy, cancer was detected in 62 (37.8%) patients. The mean age for the 62 patients with histologically proven prostate cancer was 62.3+/-5.5 years (49-73). The histological findings were compared with the free/total PSA ratio. Pearson Correlation Coefficient test and Chi-Square test (chi2-test) were used for statistical analysis and p<0.05 was considered statistically significant.


RESULTS
Of the 62 patients, 37 (59.7%) patients had cancers of low Gleason scores (score 2-6) and 25 (40.3%) patients had cancers of high Gleason scores (score 7-10). Free PSA<0.15% was found in 19 (30.6%) patients, from 15 to 20% in 23 (37.1%) patients and >20% in 20 (32.3%) patients. There was a significant positive correlation between total PSA and Gleason score (Pearson Correlation Coefficient test, r=0.328, p<0.01). Also, there was a significant increase in Gleason score with lower F/T PSA ratio (r=-0.668, p<0.001). Among the 19 patients with free PSA ratio<15%, 14 (73.7%) patients had cancers of high Gleason score while 5 (26.3%) patients had cancers of low Gleason score. In patients (n=23) with free PSA ratio15-20%, 10 (43.5%) had cancers of high Gleason score and 13 (56.5%) had cancers of low Gleason score. In the 20 patients with free PSA ratio>20%, 1 patient (5%), had prostate cancer of high Gleason score and the remaining 19 (95%) patients had low Gleason scores. There was a significant relation between lower F/T PSA ratios and higher Gleason scores, Chi-Square test, chi2=19.3, p<0.01.


CONCLUSIONS
In this study, men with prostate cancer and lower F/T PSA ratio were at a higher risk of having higher Gleason scores (7-10) and those with higher F/T PSA ratio were more likely to have lower Gleason scores.
Elabbady
Ahmed A
AA
Department of Urology Faculty of Medicine, University of Alexandria, Alexandria, Egypt. a_elabbady@hotmail.com
Khedr
Mahrousa M
MM
D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000473:pathology*
D017430:Prostate-Specific Antigen