Department of Urology, University Hospital Charité, University Medicine Berlin, Germany.
Eur Urol. 2010 Jul;58(1):12-8; discussion 20-1. doi: 10.1016/j.eururo.2010.01.035. Epub 2010 Jan 26.
Sarcosine in urine was recently suggested to be a promising tool in prostate cancer (PCa) diagnostics.
To reevaluate sarcosine as a potential biomarker for early PCa detection and for prediction of tumour aggressiveness.
DESIGN, SETTING, AND PARTICIPANTS: Sarcosine was measured in urine samples from 106 PCa patients and 33 patients with no evidence of malignancy (NEM), confirmed by 8-12 core prostate biopsies, after standardised digital rectal examination, as well as from 12 healthy men and women. The results were related to the clinicopathologic data on prostate volume, tumour stage, Gleason score, and prostate specific antigen (PSA).
Sarcosine in urine was determined by gas chromatography-mass spectrometry using a commercial amino acid assay and was normalised to urine creatinine. Nonparametric statistical tests and receiver operating characteristics (ROC) analyses were performed to assess the diagnostic performance.
The median sarcosine-creatinine ratio in urine was 13% lower in PCa than in NEM patients. Sarcosine values were not associated with tumour stage (pT2 vs pT3) or grade (Gleason score <7 vs > or = 7). ROC analyses proved that the discrimination between PCa and NEM patients was not improved by sarcosine in comparison with total PSA, but it was significantly worse than the percent free PSA. The higher proportion of PCa than NEM patients can be considered a limitation of this study.
Sarcosine in urine after rectal digital examination cannot be considered as a suitable marker to differentiate between patients with and without PCa.
尿液中的肌氨酸最近被认为是前列腺癌（PCa）诊断的一种很有前途的工具。
重新评估肌氨酸作为早期 PCa 检测和预测肿瘤侵袭性的潜在生物标志物。
设计、地点和参与者：在经过标准直肠指检后，对 106 例 PCa 患者和 33 例无恶性肿瘤证据（NEM）患者的尿液样本进行了肌氨酸测量，这些患者通过 8-12 个核心前列腺活检证实，同时还对 12 名健康男性和女性进行了测量。结果与前列腺体积、肿瘤分期、Gleason 评分和前列腺特异性抗原（PSA）的临床病理数据相关。
使用商业氨基酸测定法通过气相色谱-质谱法测定尿液中的肌氨酸，并将其标准化为尿肌酐。采用非参数统计检验和接收者操作特征（ROC）分析来评估诊断性能。
PCa 患者尿液中的肌氨酸-肌酐比值中位数比 NEM 患者低 13%。肌氨酸值与肿瘤分期（pT2 与 pT3）或分级（Gleason 评分<7 与≥7）无关。ROC 分析表明，与总 PSA 相比，肌氨酸对 PCa 和 NEM 患者的区分改善不明显，但明显逊于游离 PSA 百分比。PCa 患者的比例高于 NEM 患者，这可以被认为是这项研究的一个局限性。
直肠指检后尿液中的肌氨酸不能被认为是区分 PCa 患者和 NEM 患者的合适标志物。
