Using prostate-specific antigen doubling time in clinical practice.

Isolated PSA failures after definitive local therapy might precede clinically evident manifestations of recurrent disease by many years [1,2]. These biochemical failures might represent local recurrences, distant recurrences, or both, and accurately determining the site of recurrence early remains a diagnostic challenge. Independent of pretreatment and prostatectomy disease features (i.e. pretreatment PSA level, Gleason score, surgical margin status), PSA kinetics provides a useful adjunct to aid in clinical decisions [1,2]. A short PSA doubling time (PSADT) in particular has been shown to predict subsequent distant recurrences, disease-specific and overall mortality after radical prostatectomy, radiation therapy, or combined therapy [1–6].