CEA-related antigens: molecular biology and clinical significance.

The concentration of the tumor marker CA 125 in tumor tissue, cyst fluid, ascites fluid, and serum from patients with epithelial ovarian tumors was quantitated. Immunohistologic studies showed that CA 125 was present in 90% of the nonmucinous epithelial ovarian tumors. Quantitative analysis of the fluid from 57 cysts revealed that CA 125 was present in concentrations of up to 2140,000 U/ml in samples from malignant nonmucinous epithelial ovarian lesions, and up to 116,000 U/ml in mucinous tumors, but also in concentrations of up to 371,000 U/ml in benign serous cystadenomas. In contrast, pre-operative serum CA 125 levels were elevated in almost all of the patients with malignant ovarian tumors but not in most of those with benign ovarian tumors. These findings suggest that in benign ovarian tumors there is an effective barrier between the cyst fluid and the circulation that prevents the appearance of CA 125 in the serum, whereas in malignant tumors infiltrative growth leads to the release of antigen into the circulation. Furthermore, CA 125 values in ascites fluids were up to 130 times higher than the serum antigen levels, which indicates that the peritoneum serves as a barrier for high molecular weight tumor antigens. The current results show that tumor basement membranes and peritoneal barriers play a notable role in the transit of tumor antigens, one which must be taken into account in the monitoring of serum marker levels of cancer patients.

Explanation of the limited correlation between tumor CA 125 content and serum CA 125 antigen levels in patients with ovarian tumors.

Carcinomatous and Tuberculous Pleural Effusions: Comparison of Tumor Markers

The role of tumour marker assays in differentiating malignant from benign pleural effusions is not yet clear. This study was designed to prospectively assess the individual and combined diagnostic utility of three tumour markers in patients with pleural effusion. Pleural and serum levels of carcinoembryonic antigen (CEA), carbohydrate antigen 15-3 (CA 15-3) and cytokeratin 19 fragment (CYFRA 21-1) were determined in 115 patients with pleural effusions (42 malignant and 73 benign). The diagnostic utility of each tumour marker was assessed using accuracy to determine the optimal cut-off point, whilst a logistic regression model was used to obtain the optimal combined test. In serum, every marker showed an individual high specificity (over 97%) for malignancy. The sensitivity of CEA, CA 15-3 and CYFRA 21-1 was 36, 48 and 31%, respectively. In patients without renal failure, the sensitivity of CYFRA 21-1 rose to 53%, while those of CEA and CA 15-3 remained almost unchanged. In pleural fluid, CYFRA 21-1 showed low sensitivity (32%) and specificity (82%), while CEA showed the highest sensitivity (57%). Excluding patients with renal failure, the combined determination in serum of CEA, CA 15-3 and CYFRA 21-1 has a high accuracy (88%), similar to that for CEA plus CA 15-3 in pleural fluid (87%). We conclude that CYFRA 21-1 is useless in pleural fluid and should not be used in serum for patients with renal failure. The combined determination of CEA, CA 15-3 and CYFRA 21-1 in serum may obviate its determination in pleural fluid.

https://erj.ersjournals.com/content/erj/9/1/17.full.pdf

CEA, CA 15-3 and CYFRA 21-1 in serum and pleural fluid of patients with pleural effusions

Background and objective:  Conventional tests are not always helpful in making a diagnosis of malignant pleural effusion (MPE). Many studies have investigated the utility of pleural carcinoembryonic antigen (CEA) in the early diagnosis of MPE. The present meta-analysis determined the accuracy of CEA measurement in the diagnosis of MPE.



Methods:  A systematic review of English language studies was conducted and data on the accuracy of pleural CEA concentrations in the diagnosis of MPE were pooled using random effects models. Receiver operating characteristic curves were used to summarize the overall test performance.



Results:  Forty-five studies met the inclusion criteria for the meta-analysis. The summary estimates for CEA in the diagnosis of MPE were: sensitivity 0.54 (95% CI: 0.52–0.55), specificity 0.94 (95% CI: 0.93–0.95), positive likelihood ratio 9.52 (95% CI: 6.97–13.01), negative likelihood ratio 0.49 (95% CI: 0.44–0.54) and diagnostic odds ratio 22.5 (95% CI: 15.6–32.5). Analysis of a subset of 11 studies which examined the value of pleural CEA in ruling out a diagnosis of malignant mesothelioma found that the sensitivity and specificity of a CEA level exceeding cut-off values were 0.97 (95% CI: 0.93–0.99) and 0.60 (95% CI: 0.55–0.65), respectively.



Conclusions:  Measurement of pleural CEA is likely to be a useful diagnostic tool for confirming MPE, and is also helpful in the differential diagnosis between malignant pleural mesothelioma and metastatic lung cancer. The results of CEA assays should be interpreted in parallel with clinical findings and the results of conventional tests.

Diagnostic value of carcinoembryonic antigen in malignant pleural effusion: a meta-analysis.

In order to discriminate between benign and malignant effusions, the value of carcinoembryonic antigen (CEA), alpha 1-acidglycoprotein (AGP), alpha-fetoprotein (AFP), phosphohexose isomerase (PHI), and beta 2-microglobulin (B2M) has been estimated in serous effusions in a group of 106 patients, 30 with a malignant and 76 with a benign effusion. Mean CEA and AGP levels in malignant effusions were significantly higher than in benign effusions; no significant differences of mean PHI, AFP and B2M levels of benign and malignant effusions were found. CEA level estimations were useful for confirming malignancy in 27% of malignant effusions but in only 7.5% of all effusions, and AGP and PHI for excluding it in 37.5 and 36.0% of all effusions, respectively. With the combination of CEA with AGP or PHI, a correct diagnosis was achieved in only 45 and 44% of all effusions, respectively. The combination of AFP or B2M with CEA, AGP or PHI did not improve the discriminative value for differentiating malignant and benign effusions.

Diagnostic value of tumoral markers in serous effusions. Carcinoembryonic antigen, alpha1‐acidglycoprotein, alpha‐fetoprotein, phosphohexose isomerase, and Beta2‐microglobulin

M. Elena

Papers

Diagnostic value of tumoral markers in serous effusions. Carcinoembryonic antigen, alpha1‐acidglycoprotein, alpha‐fetoprotein, phosphohexose isomerase, and Beta2‐microglobulin