PlVKA-ll用于诊断肝细胞肝癌临界值灵敏度及特异性评价▲

摘要

目的:评价化学发光微粒子免疫法(CMIA)与化学发光酶免疫法(CLEIA)检测异常凝血酶原(Protein Induced by Vitamin K Absence or Antagonist-II, PIVKA-II),通过ROC曲线计算用于诊断肝癌的临界值,并对该临界值灵敏度和特异性进行评价.方法:选取我院118例肝癌患者及80例肝硬化患者的血清样本,在肝癌组中依照美国临床实验室标准化协会指南比对标准文件EP9-A2,对两种检测方法之间的偏倚进行评估;比较两组病例中PIVKA-II检测水平,以临界值(CUT OFF) 40mAU/mL为参考线,分析两种检测对肝癌的诊断特异性.结果:两种方法检测PIVKA-II相关性良好, r =0.9993,直线回归方程为Y=0.42667+0.99694X ,在PIVKA-Ⅱ阳性参考限40 mAU/mL,其预期的偏倚值95%可信区间为37.959-42.649mAU/mL,两种方法在肝癌组阳性率分别为88.14%与87.29%,差异均有统计学意义(P<0.05),对肝癌诊断的ROC曲线下面积分别为0.884和0.880.提示两种检测方法对PIVKA-II肝癌诊断有均有较高的特异性.结论: CMIA与CLEIA两种方法均能有效检测PIVKA-II,且相关性良好,基于PIVKA对肝细胞癌灵敏度的临界值40mAU/mL来诊断肝癌,均有较高的特异性,能够满足临床需要.%Objective: To evaluate the PIVKA-II ( Protein Induced by Vitamin K Absence or Antagonist-II) measured by chemiluminescent microparticle immunoassay ( CMIA) and chemiluminescent enzyme immunoassay ( CLEIA) , and to estimate the sensitivity and specificity of the threshold calculated by ROC curve for diagnosis of liver cancer. Methods: Serum samples from 118 patients with liver cancer and 80 patients with liver cirrhosis in our hospital were selected. The bias between the two methods were evaluated in the liver cancer group according to comparison standard document EP9-A2 of the guidelines of the American Society for Clinical Laboratory Standards. The levels of PIVKA-II between the two groups were compared and the critical value (CUT OFF) of 40 mAU/mL was used as a reference line to analyze the diagnostic specificity of the two test methods for liver cancer. Results: The two methods were well correlated in the determination of PIVKA-II, r=0.9993, and the linear regression equation was Y=0.42667+0.99694X. When the positive reference limit of PIVKA-II was 40 mAU/mL, the 95% confidence interval of the expected bias value was 37.959-42.649mAU/mL. The positive rates of the two methods in the liver cancer group were 88.14% and 87.29%, respectively, and the difference was statistically significant (P<0.05). The area under the ROC curve for diagnosis of liver cancer was 0.884 and 0.880, respectively, suggesting that the two test methods have high specificity for the diagnosis of PIVKA-II liver cancer. Conclusion: Both CMIA and CLEIA can effectively detect PIVKA-II and have good correlation. Based on the critical value of PIVKA sensitivity to hepatocellular carcinoma of 40 mAU/mL to diagnose liver cancer, they both have high specificity and can meet clinical needs well.