The clinical potential of pretreatment serum testosterone level to improve the efficiency of prostate cancer screening.

OBJECTIVES The aim of the present study was to evaluate the clinical value of the pretreatment serum testosterone (T) level as a potential predictor of prostate cancer risk in screening for prostate cancer. MATERIALS AND METHODS The subjects were 420 patients suspected of having prostate cancer who underwent prostate biopsy, and whose pretreatment T levels were recorded. We checked for association between the presence of prostate cancer and the following clinical factors: pretreatment serum T level, age, pretreatment prostate-specific antigen (PSA) level, digital rectal examination findings, ratio of free to total PSA, prostate volume, and PSA density (PSAD). RESULTS Overall, there was no significant difference in mean pretreatment T level between patients diagnosed with cancer (3.9+/-2.4 ng/ml) and patients diagnosed with benign prostate disease (BPD; 3.7+/-1.7 ng/ml); diagnosis was based on prostate biopsy. However, among patients with PSA <10 ng/ml, the pretreatment T level was significantly higher in patients diagnosed with prostate cancer (4.2+/-2.6 ng/ml) than in patients diagnosed with BPD (3.6+/-1.4 ng/ml) (p=0.007); a similar trend was observed among patients with PSAD <0.15 ng/ml/cc. Multivariate analysis indicated that pretreatment T level was an independent significant predictor of positive prostate biopsy (p=0.020). Additionally, the serum T level was significantly lower in patients with a Gleason score >or=7 (3.7+/-2.1 ng/ml) versus a score <7 (4.2+/-1.7 ng/ml) (p=0.030). Also, serum T levels were significantly higher in well-differentiated prostate cancer (4.8+/-2.1 ng/ml) versus moderately differentiated (3.8+/-1.3 ng/ml) or poorly differentiated (3.7+/-1.4 ng/ml) (p<0.01). CONCLUSIONS Among relatively low-risk patients, serum T level was an independent significant predictor of positive prostate biopsy, suggesting that the efficiency of prostate cancer screening can be improved by including measurement of serum T level.