Bruwer G, Heyns C F, Allen F J
Department of Urology, Faculty of Medicine, University of Stellenbosch and Tygerberg Hospital, South Africa.
Eur Urol. 1999;35(3):223-7. doi: 10.1159/000019850.
To determine whether serum prostate-specific antigen (PSA) can be reliably used to predict the absence or presence of skeletal metastases on the bone scan in patients with adenocarcinoma of the prostate.
We studied 450 consecutive men presenting with adenocarcinoma of the prostate between 1991 and 1995. Serum PSA was measured by the Hybritech Tandem-R monoclonal immunoradiometric assay and bone scanning was performed with 99m-technetium-labelled methylene diphosphonate. In total, 46 patients were excluded for one or more of the following reasons: serum PSA not available; radionuclide bone scan inconclusive; histology of the prostate other than adenocarcinoma; hormonal or other therapy given prior to obtaining the serum PSA and/or bone scan.
Of the 404 patients included, 43% had poorly differentiated (grade 3), 74% had locally advanced (stages T3-4) tumours and 50% had skeletal metastases. The mean and median serum PSA were 348 and 52 ng/ml, respectively, and 77% of the patients had a serum PSA >20 ng/ml. The negative predictive value (for the absence of metastases on bone scan) of a serum PSA <20 ng/ml was 87% for the whole group of patients, 92, 94 and 70% for grade 1, 2 and 3 tumours, and 95, 83 and 50% for stage T1-2, T3 and T4 tumours, respectively. The positive predictive value (for the presence of metastases on bone scan) of a serum PSA >100 ng/ml was 80% for the whole group of patients.
In patients presenting with adenocarcinoma of the prostate, serum PSA alone is not sufficiently reliable to predict the absence or presence of metastases on the radionuclide bone scan. In patients with grade 3 and clinical stage T3-4 tumours, a bone scan should be obtained for accurate staging, regardless of the serum PSA value.
确定血清前列腺特异性抗原（PSA）能否可靠地用于预测前列腺腺癌患者骨扫描中骨转移的有无。
我们研究了1991年至1995年间连续就诊的450例前列腺腺癌男性患者。采用Hybritech Tandem - R单克隆免疫放射测定法检测血清PSA，并用99m锝标记的亚甲基二膦酸盐进行骨扫描。共有46例患者因以下一种或多种原因被排除：血清PSA数据不可得；放射性核素骨扫描结果不明确；前列腺组织学类型不是腺癌；在获取血清PSA和/或骨扫描之前接受过激素或其他治疗。
纳入的404例患者中，43%为低分化（3级）肿瘤，74%为局部晚期（T3 - 4期）肿瘤，50%有骨转移。血清PSA的平均值和中位数分别为348 ng/ml和52 ng/ml，77%的患者血清PSA>20 ng/ml。血清PSA<20 ng/ml时，对全组患者骨扫描无转移的阴性预测值为87%，对1级、2级和3级肿瘤分别为92%、94%和70%，对T1 - 2期、T3期和T4期肿瘤分别为95%、83%和50%。血清PSA>100 ng/ml时，对全组患者骨扫描有转移的阳性预测值为80%。
对于前列腺腺癌患者，仅血清PSA不足以可靠地预测放射性核素骨扫描中转移的有无。对于3级及临床T3 - 4期肿瘤患者，无论血清PSA值如何，都应进行骨扫描以准确分期。
