Kurita Y, Terada H, Masuda H, Suzuki K, Fujita K
Department of Urology, Hamamatsu University School of Medicine, Japan.
Br J Urol. 1998 Aug;82(2):224-30. doi: 10.1046/j.1464-410x.1998.00696.x.
To determine: (i) whether the accuracy of prostate-specific antigen (PSA) density is improved by using the transition zone (TZ) volume instead of total prostate volume, with the gamma-seminoprotein (gamma SP, a measure of free PSA) to total PSA ratio, for detecting prostate cancer; and (ii) to assess the influence of prostate volume on PSA density and gamma SP/PSA ratio.
From April 1995 to July 1997, 297 consecutive patients (46-88 years old) were examined; all had intermediate serum PSA levels (4-10 ng/mL) and/or abnormal findings on digital rectal examination. All patients underwent transrectal ultrasonography (TRUS)-guided biopsy, and the prostate and TZ volumes determined from TRUS. The PSA density relative to the total prostate volume (PSAD) and to the TZ volume (PSAT) were then calculated. The total PSA and gamma SP levels were measured before the diagnostic procedures.
Of the 297 patients, 62 (21%) were histologically confirmed to have prostate cancer by biopsy. The area under the receiver operating characteristic curve was 0.680 for PSA, 0.684 for PSAD, 0.764 for PSAT, 0.748 for gamma SP/PSA, 0.885 for gamma SP/PSA in patients with a prostate volume < 40 mL, while it was 0.817 for PSAT in patients with a prostate volume of > or = 40 mL. Using a PSAT threshold of 0.17 in patients with a prostate volume of 40 mL, the number of biopsies was reduced by 56% (66 of 118) and 22 of the 25 cancers (88%) were detected. In addition, a gamma SP/PSA ratio threshold of 40% in patients with a prostate volume of < 40 mL decreased the number of biopsies by 75% (88 of 117) and detected 32 of the 37 cancers (87%).
Prostate volume was significantly and positively correlated with gamma SP/PSA and negatively correlated with PSAT. Among patients with a PSA level of 4-10 ng/mL, a low gamma SP/PSA was most useful for detecting prostate cancer when the prostate volume was < 40 mL and a high PSAT was useful when the prostate volume was > or = 40 mL.
确定：（i）在检测前列腺癌时，使用移行区（TZ）体积而非前列腺总体积，结合γ-精浆蛋白（γSP，游离PSA的一种测量指标）与总PSA比值，是否能提高前列腺特异性抗原（PSA）密度的准确性；以及（ii）评估前列腺体积对PSA密度和γSP/PSA比值的影响。
1995年4月至1997年7月，对297例连续患者（46 - 88岁）进行检查；所有患者血清PSA水平处于中等范围（4 - 10 ng/mL）和/或直肠指检有异常发现。所有患者均接受经直肠超声（TRUS）引导下活检，并通过TRUS测定前列腺和TZ体积。然后计算相对于前列腺总体积（PSAD）和TZ体积（PSAT）的PSA密度。在诊断程序前测量总PSA和γSP水平。
297例患者中，62例（21%）经活检组织学确诊患有前列腺癌。前列腺癌患者的受试者操作特征曲线下面积，PSA为0.680，PSAD为0.684，PSAT为0.764，γSP/PSA为0.748，前列腺体积<40 mL患者的γSP/PSA为0.885，而前列腺体积≥40 mL患者的PSAT为0.81。对于前列腺体积为40 mL的患者，采用PSAT阈值0.17时，活检次数减少56%（118例中的66例），25例癌症中的22例（88%）被检测到。此外，对于前列腺体积<40 mL的患者，采用γSP/PSA比值阈值40%时，活检次数减少75%（117例中的88例），37例癌症中的32例（87%）被检测到。
前列腺体积与γSP/PSA显著正相关，与PSAT显著负相关。在PSA水平为4 - 10 ng/mL的患者中，前列腺体积<40 mL时，低γSP/PSA对检测前列腺癌最有用，而前列腺体积≥40 mL时，高PSAT对检测前列腺癌最有用。
