Prostate cancer percent free psa value over 24 is increasingly being used as an indicator for biopsy with total free psa values are between 4 and 10 according the the following exerpt from a US News report developed in conjunction with Johns Hopkins medicine. This combined test ratio is very likely a good thing and will probably reduce the number of biopsies that previously were done when unnecessary

Measuring the ratio of free to total PSA (percent free PSA) PSA in the blood is either bound (attached to proteins) or unbound (free). Men with prostate cancer have a higher percentage of bound PSA and a lower percentage of free PSA than men with benign prostatic hyperplasia (BPH). Research suggests that determining the ratio of free to total PSA in the blood helps distinguish between PSA elevations due to cancer and those caused by BPH. In men with PSA levels between 4 and 10 ng/mL, performing a prostate biopsy only when the percent free PSA is 24 percent or below would result in the detection of 90 percent of prostate cancers and reduce by 20 percent the number of unnecessary biopsies. Percent free PSA, as well as PSA density and PSA velocity, can also be used to determine the need for a repeat biopsy when the initial biopsy shows no evidence of cancer but cancer is still suspected.