ROC曲线分析波谱定量分析在前列腺癌中的诊断价值

Clinical value of magnetic resonance spectroscopy by ROC curve in diagnosis of prostate cancer

目的:探讨MR波谱(magnetic resonance spectroscopy,MRS)定量分析方法在前列腺癌(prostatic carci-noma,PCa)诊断中的意义。方法:对所有疑诊PCa患者行前列腺磁共振波谱分析,酶联免疫法测定血清前列腺特异抗原(PSA),经直肠超声测定前列腺体积,计算前列腺特异抗原密度(PSAD),经超声引导下系统穿刺活检证实的71例良性前列腺增生患者和31例PCa患者,分别测量各个位置(胆碱+肌酸)/枸橼酸盐[(Cho+Cre)/Cit]的比值,并取均值。结果:前列腺穿刺阳性组的PSA、PSAD及(Cho+Cre)/Cit的比值分别为23.73±19.06、0.62±0.42、2.33±0.66;前列腺穿刺阴性组的PSA、PSAD及(Cho+Cre)/Cit的比值分别为8.61±4.47、0.15±0.13、0.73±0.39。阳性组的检测值均较阴性组高(P<0.05)。PSA、PSAD及(Cho+Cre)/Cit在ROC曲线下的面积分别为0.71、0.76、0.84。在保持93.5%的敏感性以上时,PSA、PSAD及(Cho+Cre)/Cit的特异性是43.7%、63.4%和83.1%,(Cho+Cre)/Cit较PSA、PSAD能更好地检出PCa。结论:MRS分析方法定量评价PCa的代谢改变,有助于PCa的早期诊断,同时结合PSA、PSAD更有助于前列腺癌诊断的特异性。

Objective：To evaluate the value of magnetic resonance spectroscopy（MRS）in diagnosis of prostate adenocarcinoma.Methods： All patients were scanned by magnetic resonance imagnetic,the measurement of PSA was performed by ELISA,the volume of prostate was measured by transrectal ultrasound and calculate the PSAD.All 71 patients with benign prostate（BPH）and 31 patients with prostate cancer were proved by ultrasound guided systemic biopsy were enrolled in this study.All the puncture locations were marked and the corresponding（Choline＋Creatine）/Citrate ratios were calculated on the basis of MRS metabolicmap.Results： The PSA,PSAD and the average（Cho＋Cre）/Cit ratio in PCa were 23.73±19.06,0.62±0.42 and 2.333±0.66,respectively;The PSA,PSAD and the average（Cho＋Cre）/Cit ratio in BPH were 8.61±4.47,0.15±0.13 and 0.73±0.39,respectively.They were significantly higher in PCa group than that in BPH group（P0.05）.The area under ROC curve for PSA,PSAD and（Cho＋Cre）/Cit ratio were 0.71,0.76 and 0.84,respectively.While holding 93.5% sensitivity,the specificity of PSA,PSAD and（Cho＋Cre）/Cit ratio were 43.7%、63.4% and 83.1%,respectively.The（Cho＋Cre）/Cit ratio were better than PSA and PSAD in diagnosis of PCa.Conclusion： MRS analysis method for quantitative evaluation of metabolic changes of the PCa is helpful to the early diagnosis,combined with PSA,PSAD,is more helpful to the specificity.