You would be advised to research this more deeply. The understanding of this has changed considerably since the 2007 paper you cite. In a very thorough analysis of all available studies on the subject in 2013, Andrew Vickers, the head of research at Memorial Sloan Kettering, found the following:
Andrew Vickers (2013) said...
Before using PSA velocity to inform decisions such as whether or not to biopsy a man, there should be clear evidence that doing so would improve clinical outcome. A systematic review on PSA velocity found that almost no studies had evaluated whether PSA velocity aids clinical decision-making. Since that time, several reports have indicated that including PSA velocity in a statistical model alongside standard predictors (such as PSA and digital rectal exam) does not improve predictive accuracy. Specifically, biopsying men with high PSA velocity in the absence of other indications, as recommended by the NCCN guidelines, would lead to many millions of unnecessary biopsies, without a corresponding number of aggressive cancers being detected. Advocates of PSA velocity have been reduced to citing a single paper purporting to show that PSA velocity aids clinical decision-making. The paper involves selective reporting of an unusual subgroup analysis based on an extremely limited number of events. This is not to say that, in clinical practice, urologists should ignore prior PSA values: clinical judgment can be aided by careful longitudinal evaluation of PSA changes, interpreted in the context of symptoms and treatments. However, the literature clearly demonstrates that simplistic application of PSA velocity cut-offs is not of value for early detection of prostate cancer.
Here's his full review:Prostate-specific antigen velocity is not of value for early detection of cancer
Vickers joined the top urologists from UTHS, Cleveland Clinic, UCSF & MSKCC in making the following recommendations:
The top US urologists said...www.goldjournal.net/article/S0090-4295(13)01535-5/abstract
Recent studies, including analyses of cohorts from all the major randomized trials of localized prostate cancer, have failed to find any evidence that PSA velocity and application of PSA cutpoints are of benefit in this setting. Given current data on PSA velocity and doubling time, we propose the following "take home" messages for the practicing urologist:
(1) High PSA velocity is not an indication for biopsy;
(2) for men with a low total PSA but a high PSA velocity, consideration should be given to having PSA taken at a shorter interval;
(3) men with an indication for biopsy should be biopsied irrespective of PSA velocity;
(4) changes in PSA after negative biopsy findings do not determine the need for repeat biopsy;
(5) monitoring PSA over time can aid judgment in decisions about biopsy, as informed by the clinical context;
(6) PSA velocity is uninformative of risk at diagnosis;
(7) high PSA velocity is not an indication for treatment in men on active surveillance;
(8) PSA velocity at the time of recurrence should be entered into prediction models (or "nomograms") to aid patient counseling;
(9) PSA changes after treatment for advanced disease can help indicate therapeutic response.