Gregorakis Alkiviades K, Malovrouvas Dimitrios, Stefanakis Stefanos, Petraki Konstantina, Scorilas Andreas
Urology Department, Attikon General Hospital, University of Athens, Athens, Greece.
Clin Chim Acta. 2005 Jul 24;357(2):196-201. doi: 10.1016/j.cccn.2005.03.027.
In this paper we study the Free/Total PSA kinetics in patients with clinically localized prostate cancer undergoing radical prostatectomy.
Serum PSA, Free PSA and Free/Total Ratio were determined preoperatively, at the time of prostate removal (0 time) and then at 3, 6, 12, 24, 48, 72 and 168 h, from 9 patients with clinically localized prostate cancer who underwent radical retropubic prostatectomy. The elimination rates and half-lives of Total, Free PSA and F/T Ratio were studied applying one and two compartment models for pharmacokinetic analysis.
Surgical manipulations of the prostate caused a mean 2.16-fold increase of PSA, 12-fold increase of free PSA and 4.2-fold increase of F/T PSA ratio. Removal of the prostate caused a rapid biphasic, biexponential elimination of Free PSA with a mean half-life of 0.8 h for the alpha (a) phase and 32.6 h for the beta (b) phase. PSA was eliminated following a rapid exponential (a) phase with a half-life of 1.15 h and a non-exponential (b) phase with a half-life of 71.96 h. Free/Total PSA followed a biphasic kinetic, with an initial exponential elimination phase and a mean half-life of 2.6 h and a second non-exponential increase phase with a doubling time of 130.8 h. Free/Total PSA reached its nadir very soon, at the first postoperative 24 h.
Free/Total PSA kinetic after radical prostatectomy reflects the differences of Free and Total PSA elimination kinetics. Free/Total Ratio follows a biphasic kinetic, with an initial rapid exponential elimination phase, which is affected mainly by the rapid exponential (a) phase of Free PSA elimination and a second slow increase, which is affected mainly by the terminal non-exponential (b) phase of PSA elimination.
在本文中，我们研究了接受根治性前列腺切除术的临床局限性前列腺癌患者的游离/总前列腺特异抗原（PSA）动力学。
对9例接受耻骨后根治性前列腺切除术的临床局限性前列腺癌患者，在术前、前列腺切除时（0时）以及随后的3、6、12、24、48、72和168小时测定血清PSA、游离PSA和游离/总比值。应用一室和二室模型进行药代动力学分析，研究总PSA、游离PSA和F/T比值的消除率及半衰期。
前列腺手术操作导致PSA平均升高2.16倍，游离PSA升高12倍，F/T PSA比值升高4.2倍。前列腺切除后，游离PSA呈现快速双相、双指数消除，α（a）相平均半衰期为0.8小时，β（b）相为32.6小时。PSA先经快速指数（a）相消除，半衰期为1.15小时，然后经非指数（b）相消除，半衰期为71.96小时。游离/总PSA呈现双相动力学，初始为指数消除期，平均半衰期为2.6小时，随后为非指数升高期，倍增时间为130.8小时。游离/总PSA在术后24小时很快达到最低点。
根治性前列腺切除术后游离/总PSA动力学反映了游离和总PSA消除动力学的差异。游离/总比值呈现双相动力学，初始为快速指数消除期，主要受游离PSA消除的快速指数（a）相影响，随后为缓慢升高期，主要受PSA消除的终末非指数（b）相影响。
