Serum testosterone: A potentially adjunct screening test for the assessment of the risk of prostate cancer among men with modestly elevated PSA values (> or =3.0 and <10.0 ng/ml).

Whether serum testosterone (T) can become an adjunct test able to validate the PSA-weighted risk of prostate cancer (PR.CA) in the "grey" diagnostic area (PSA =3.0 to <10.0 ng/ml) was investigated. Seven hundred and eighteen men participated in a prostate screening program using the cutoff PSA value of > or =3.0 ng/ml. PR.CA was found in 26% (22/85) of men with PSA testing within the "grey" diagnostic area and 58% (7/12) with PSA testing > or =10 ng/ml, among the 97 men who agreed to undergo transrectal ultrasound-guided biopsy (TRUS-guided biopsy). The PSA values showed a statistically significant positive association with diagnosis of PR.CA, whereas T and the T/PSA ratio were inversely and significantly related to the disease. In addition, out of 718 subjects, 45 (2.6%) were found to have a T value <2.6 ng/ml and another 78 (10.8%) had "low normal T value" (2.6> or = T <3.0 ng/ml). Of the hypogonadal men, 16 received testosterone enanthate (depot T; 250 mg/ml oily injection, intramuscularly: i.m.; TRT) and three had PSA levels >3.0 ng/mlpost-TRT; one was eventually diagnosed with PR.CA. An empirically-determined cut-off of the T/PSA ratio [>95 ("negative") or <0.95 ("positive")] was found to be optimal with regard to both sensitivity/specificity. This test was "positive" among 95.5% of the PR.CA patients, whereas 81% of biopsies confirmed that non-PR.CA had a "negative" TIPSA ratio, indicating that this ratio can become an adjunct screening test in assessing the risk of PR. CA; in particular, the odds of PR. CA increasing sharply (1/0.08= 12.5 times) with a decrease of the TIPSA ratio by one standard deviation. We conclude that the measurement of the serum T value can become an adjunct test validating further the PSA-weighted risk of PR. CA within the "grey" diagnostic area.