Buraggi G L, Bombardieri E, Castellani M R, Rodari A, Crippa F
Tumori. 1981 Dec 31;67(6):553-8. doi: 10.1177/030089168106700607.
The authors evaluate the combined use of liver scan and the CEA test in the diagnosis of hepatic metastases of carcinoma of the gastrointestinal tract. Association of the two tests is justified by the fact that the liver scan is very specific but not very sensitive, whereas the CEA test is more sensitive and not very specific. The sensitivity of the CEA test, on the other hand, can be increased by increasing the threshold of normality. However, the associated diagnostic use of the liver scan and the CEA test gives a loss of specificity with respect to the use of the liver scan alone. The present study, carried out on a series of 376 patients affected by gastrointestinal tumors of which 79 were of the stomach (9 with hepatic metastases), 133 of the colon and higher sigmoid (25 with hepatic metastases), and 164 of the lower sigmoid and rectum (29 with hepatic metastases), proposed to establish by use of a statistical method the optimal threshold of the CEA test that would give the best diagnostic specificity of the combined CEA test and liver scan without any relevant loss of sensitivity. A threshold of 26 ng/ml of the CEA test and gave a specificity of 92%, a sensitivity of 80%, and an accuracy of 90%. The authors think that in the detection of liver metastases of gastrointestinal tumors, the combined test can be more helpful the less the probability, for a given patient, for other metastatic localizations.
作者评估了肝脏扫描和癌胚抗原（CEA）检测联合应用于诊断胃肠道癌肝转移的情况。两种检测方法联合应用的依据是，肝脏扫描特异性很强但灵敏度不高，而CEA检测灵敏度较高但特异性不强。另一方面，通过提高正常阈值可以提高CEA检测的灵敏度。然而，与单独使用肝脏扫描相比，肝脏扫描和CEA检测联合诊断会导致特异性降低。本研究对376例胃肠道肿瘤患者进行了分析，其中79例为胃癌（9例有肝转移），133例为结肠和乙状结肠上段癌（25例有肝转移），164例为乙状结肠下段和直肠癌（29例有肝转移），旨在通过统计学方法确定CEA检测的最佳阈值，以在不显著降低灵敏度的情况下，使CEA检测与肝脏扫描联合应用时具有最佳诊断特异性。CEA检测阈值为26 ng/ml时，特异性为92%，灵敏度为80%，准确率为90%。作者认为，在检测胃肠道肿瘤肝转移时，对于特定患者，其他转移部位的可能性越小，联合检测越有帮助。
