Editorial Comment on: Current Applications forProstate-Specific Antigen Doubling TimeAndrea GallinaDepartment of Urology, Vita-Salute University,Milan, Italygallina_andrea_1979@yahoo.it

Pierre I. KarakiewiczCancer Prognostics and Health Outcomes Unit,University of Montreal Health Center, Montreal,QC, Canadapierre.karakiewicz@umontreal.ca,prost8@videotron.ca

Prostate-specific antigen doubling time (PSADT)holds great promise for the prediction of cancercharacteristics, such as stage and probability ofprogression before the delivery of definitive ther-apy [1–4]. Similarly, PSADT appears to have theability to predict the probability of prostate cancer(PCa) diagnosis, especially after a previouslynegative biopsy. Moreover, PSADT was shown topredict progression towards lethal PCa phenotypesafter radiation or surgery. Finally, PSADT repre-sents one of the most powerful predictors ofPCa-specific mortality in men with androgen-insensitive prostate cancer (AIPC) [5]. PSADTcalculators are available at several PCa-orientedWeb sites, such as the MSKCC site (www.nomo-grams.org) or the University of Montreal site(www.nomogram.org). The PSADT calculatorsallow the clinician to define the PSADT value ofthe individual patient at a given time. This metricshowed promise as an independent predictor ofcancer outcomes at different stages of the naturalhistory of treated prostate cancer. Unfortunately,the current reports which showcase the value ofPSADT might at times be difficult to interpret andeven more difficult to implement. The problemrelates to different PSADT cut-offs that are sug-gested as ‘‘ideal’’ predictors of unfavorable out-come. As a result, the clinician might not be able toderive the full benefit of the information containedwithin this powerful marker. Svatek et al circum-vented the problem related to the interpretation ofvarious PSADT cut-offs and integrated PSADTwithin a prognostic nomogram for men with AIPC

[5]. Of all predictors, PSADT was the most infor-mative, and accomplished its prognostic role forprediction of PCa-specific mortality in noncategor-ized format. Svatek et al demonstrated that thispowerful predictor can result in most accuratepredictions and can yield the best calibration,when it was combined with three other informa-tive and significant variables [5]. Most importantly,these researchers proved that PSADT can be usedto provide individualized predictions, which can beeasily interpreted (prognosis expressed as a prob-ability from 0–100% of dying from PCa at differenttime points) and can be equally easily accessed bypatients and/or physicians (www.nomogram.org).Hopefully, more researchers will reexamine theirvaluable findings and will attempt to integratePSADT within prognostic models capable of pro-viding evidence-based, individualized prognosticinformation. Such measures would certainly resultin much wider use of PSADT and would possiblyimprove patient care.

References

[1] Ramı́rez ML, Nelson EC, deVere White RW, Lara Jr PN,

Evans CP. Current applications for prostate-specific anti-

gen doubling time. Eur Urol 2008;54:291–302.

[2] Maffezzini M, Bossi A, Collette L. Implications of pros-

tate-specific antigen doubling time as indicator of failure

after surgery or radiation therapy for prostate cancer.

Eur Urol 2007;51:605–13.

[3] Yossepowitch O, Bianco Jr FJ, Eggener SE, Eastham JA,

Scher HI, Scardino PT. The natural history of nonca-

strate metastatic prostate cancer after radical prosta-

tectomy. Eur Urol 2007;51:940–8.

[4] Studer UE, Collette L, Whelan P, et al. Using PSA to guide

timing of androgen deprivation in patients with T0–4

N0–2 M0 prostate cancer not suitable for local curative

treatment (EORTC 30891). Eur Urol 2008;53:941–9.

[5] Svatek R, Karakiewicz PI, Shulman M, Karam J, Perrotte P,

Benaim E. Pre-treatment nomogram for disease-

specific survival of patients with chemotherapy-naive

androgen independent prostate cancer. Eur Urol 2006;

49:666–74.

DOI: 10.1016/j.eururo.2008.04.006

DOI of original article: 10.1016/j.eururo.2008.04.003

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