Takayama T K, Vessella R L, Brawer M K, Noteboom J, Lange P H
Department of Urology, University of Washington Medical Center, Seattle.
J Urol. 1993 Aug;150(2 Pt 1):374-8. doi: 10.1016/s0022-5347(17)35486-1.
Prostate specific antigen (PSA) determinations after radical prostatectomy are valuable in detecting persistent disease. Previously, we determined that 0.4 ng./ml. PSA was a reliable clinical threshold using the Hybritech Tandem-R PSA assay. Recently, we reported that a new PSA immunoassay (Abbott IMx PSA) correlated well with results of the Tandem-R immunoradiometric PSA assay and had a lower threshold. Using a conservative threshold of 0.1 ng./ml. PSA for the IMx PSA assay, we analyzed IMx PSA values in serial postoperative serum from 72 radical prostatectomy patients whose initial Tandem-R levels were less than 0.4 ng./ml. PSA. The lower detection limits of the IMx PSA assay allowed approximately a third (15 of 42) more detection of persistent disease within 8 months of surgery. When the PSA level remained undetectable for more than 8 months but the disease eventually recurred the lead times averaged 9 to 12 months when 0.1 ng./ml. PSA was used to signify persistent disease. All patients whose PSA levels reached 0.1 ng./ml. PSA and were subsequently followed for more than 3 months continued to have increasing levels. Also, every man who eventually had recurrence also had a PSA serum level of at least 0.1 ng./ml. PSA within 28 months postoperatively, although the subsequent increase from 0.1 to 0.4 ng./ml. PSA sometimes took several years. Although the clinical impact of these findings is yet unknown, new or altered PSA assays with lower detection limits can provide unique information that may offer opportunities for improved clinical investigation and possibly patient management.
前列腺癌根治术后测定前列腺特异性抗原（PSA）对于检测残留疾病很有价值。此前，我们使用Hybritech Tandem-R PSA检测法确定0.4 ng/ml PSA是一个可靠的临床阈值。最近，我们报告了一种新的PSA免疫测定法（雅培IMx PSA）与Tandem-R免疫放射测定PSA检测法的结果相关性良好，且阈值更低。使用IMx PSA检测法0.1 ng/ml PSA的保守阈值，我们分析了72例前列腺癌根治术患者术后系列血清中的IMx PSA值，这些患者最初的Tandem-R水平低于0.4 ng/ml PSA。IMx PSA检测法较低的检测限使得在术后8个月内能够多检测出约三分之一（42例中的15例）的残留疾病。当PSA水平在8个月以上未被检测到但疾病最终复发时，以0.1 ng/ml PSA表示残留疾病时，提前期平均为9至12个月。所有PSA水平达到0.1 ng/ml PSA且随后随访超过3个月的患者，其PSA水平持续升高。此外，每例最终复发的男性在术后28个月内血清PSA水平至少达到0.1 ng/ml PSA，尽管随后从0.1 ng/ml PSA升高到0.4 ng/ml PSA有时需要数年时间。尽管这些发现的临床影响尚不清楚，但具有更低检测限的新型或改良PSA检测法可以提供独特信息，可能为改善临床研究以及患者管理提供机会。
