Tochigi T, Kawamura S, Numahata K, Tokuyama S, Kuwahara M, Horaguchi T, Satou S
Department of Urology, Miyagi Cancer Center, Horaguchi Hospital, Satou Clinic.
Nihon Hinyokika Gakkai Zasshi. 2001 Sep;92(6):609-14. doi: 10.5980/jpnjurol1989.92.609.
We examined the usefulness of prostate specific antigen density (PSAD) for selection of biopsy candidate with prostate specific antigen levels between 4.1 and 10.0 ng./ml. in prostate cancer screening retrospectively.
The screening was conducted on male candidates in Natori city, aged 55 years or older, for 6 years from 1994 through 1999. We could analyze serum PSA levels and PSA density in 118 men with PSA levels between 4.1 and 10.0 ng./ml. All of 118 men underwent ultrasound guided systematic prostate biopsy regardless of findings of digital rectal examination and transrectal ultrasound. Prostate volume was estimated by transrectal ultrasound measurements using the prolate ellipse formula (pi/6 x length x width x height). PSAD was calculated by dividing serum PSA level by prostate volume. Serum PSA levels were determined by Tandem-R assay.
In 118 men, twenty-five men had prostate cancer. There was no significant difference in mean PSA between those with prostate cancer and those without prostate cancer, but the difference was significant in the mean PSA density (mean 0.26 and 0.16, respectively, p < 0.0001). Receiver operating characteristic curves for PSA and PSAD demonstrated superior benefit for PSAD in 118 men. A sensitivity, a specificity, a positive predictive value and a negative predictive value of PSAD cut-off of 0.15 were 88%, 52.7%, 33.3% and 94.2%. PSAD cut-off of 0.18 showed the highest sum of sensitivity and specificity, which gave a sensitivity of 80%, a specificity of 72%, a positive predictive value of 43.5% and a negative predictive value of 93.1%. PSAD cut-off of 0.15 would seem to be preferable to cut-off of 0.18 because of less cancer missing.
Although further studies are needed to determine optimal cut-off value to be used in clinical practice, PASD seems to be useful for the selection of biopsy candidates with PSA levels of 4.1 to 10.0 ng./ml. in the prostate cancer screening.
我们回顾性研究了前列腺特异性抗原密度（PSAD）在前列腺癌筛查中对前列腺特异性抗原水平在4.1至10.0 ng/ml之间的活检候选者选择的有用性。
从1994年至1999年，对名取市55岁及以上的男性候选者进行了为期6年的筛查。我们能够分析118名前列腺特异性抗原水平在4.1至10.0 ng/ml之间的男性的血清前列腺特异性抗原（PSA）水平和PSA密度。无论直肠指检和经直肠超声检查结果如何，这118名男性均接受了超声引导下的系统性前列腺活检。使用长椭圆形公式（π/6×长度×宽度×高度）通过经直肠超声测量来估计前列腺体积。PSAD通过将血清PSA水平除以前列腺体积来计算。血清PSA水平通过串联R测定法确定。
在118名男性中，25名患有前列腺癌。患有前列腺癌和未患前列腺癌的男性之间的平均PSA无显著差异，但平均PSA密度差异显著（分别为0.26和0.16，p<0.0001）。PSA和PSAD的受试者操作特征曲线表明，在118名男性中PSAD具有更大优势。PSAD临界值为0.15时的敏感性、特异性、阳性预测值和阴性预测值分别为88%、52.7%、33.3%和94.2%。PSAD临界值为0.18时，敏感性和特异性之和最高，敏感性为80%，特异性为72%，阳性预测值为43.5%，阴性预测值为93.1%。由于漏诊癌症较少，PSAD临界值为0.15似乎比临界值为0.18更可取。
尽管需要进一步研究以确定临床实践中使用的最佳临界值，但PSAD似乎对前列腺癌筛查中PSA水平为4.1至10.0 ng/ml的活检候选者选择有用。
