Editing Prostate-specific antigen (section)

===PSA velocity===

Despite earlier findings,<ref>{{cite journal | vauthors = Carter HB, Pearson JD, Metter EJ, Brant LJ, Chan DW, Andres R, Fozard JL, Walsh PC | title = Longitudinal evaluation of prostate-specific antigen levels in men with and without prostate disease | journal = JAMA | volume = 267 | issue = 16 | pages = 2215–2220 | year = 1992 | pmid = 1372942 | pmc = 3461837 | doi = 10.1001/jama.267.16.2215 }}</ref> recent research suggests that the rate of increase of PSA (e.g. >0.35{{nbsp}}ng/mL/yr, the 'PSA velocity'<ref>{{cite web |url=http://www.cancer.gov/cancertopics/types/prostate/research/psa-velocity-detection |title=PSA Velocity Does Not Improve Prostate Cancer Detection |date=13 April 2011| access-date=25 April 2015 }}</ref>) is not a more specific marker for prostate cancer than the serum level of PSA.<ref>{{cite journal | vauthors = Carter HB | title = Assessing risk: does this patient have prostate cancer? | journal = Journal of the National Cancer Institute | volume = 98 | issue = 8 | pages = 506–507 | date = April 2006 | pmid = 16622114 | doi = 10.1093/jnci/djj155 | doi-access = free }}</ref>

However, the PSA rate of rise may have value in prostate cancer prognosis. Men with prostate cancer whose PSA level increased by more than 2.0{{nbsp}}ng per milliliter during the year before the diagnosis of prostate cancer have a higher risk of death from prostate cancer despite undergoing [[Radical retropubic prostatectomy|radical prostatectomy]].<ref>{{cite journal | vauthors = D'Amico AV, Chen MH, Roehl KA, Catalona WJ | title = Preoperative PSA velocity and the risk of death from prostate cancer after radical prostatectomy | journal = The New England Journal of Medicine | volume = 351 | issue = 2 | pages = 125–135 | date = July 2004 | pmid = 15247353 | doi = 10.1056/NEJMoa032975 | doi-access = free }}</ref> PSA velocity (PSAV) was found in a 2008 study to be more useful than the PSA doubling time (PSA DT) to help identify those men with life-threatening disease before start of treatment.<ref>{{cite journal | vauthors = Loeb S, Kettermann A, Ferrucci L, Landis P, Metter EJ, Carter HB | title = PSA doubling time versus PSA velocity to predict high-risk prostate cancer: data from the Baltimore Longitudinal Study of Aging | journal = European Urology | volume = 54 | issue = 5 | pages = 1073–1080 | date = November 2008 | pmid = 18614274 | pmc = 2582974 | doi = 10.1016/j.eururo.2008.06.076 }}</ref>

Men who are known to be at risk for prostate cancer, and who decide to plot their PSA values as a function of time (i.e., years), may choose to use a [[semi-log plot]]. An exponential growth in PSA values appears as a straight line<ref name="SemiLog">{{cite web|title=Semi-Log Transformations of Data |url=http://wmueller.com/precalculus/families/semilog.html |access-date=4 March 2016 |url-status=bot: unknown |archive-url=https://web.archive.org/web/20160224083006/http://wmueller.com/precalculus/families/semilog.html |archive-date=24 February 2016 }}(Archived by WebCite® at )</ref> on a semi-log plot, so that a new PSA value significantly above the straight line signals a ''switch'' to a new and significantly higher growth rate,<ref name="SemiLog"/> i.e., a higher PSA velocity.