Diagnostic value of carcinoembryonic antigen in exudative pleural effusions

Tissue Polypeptide Antigen (TPA) in Pleural Effusions

The usefulness of tumor marker assay in pleural effusions for differential diagnosis is still debated. From the observation of common antigens on tissue polypeptide antigen (TPA) and keratins 8, 18 and 19 and vimentin, all substances contained in normal and neoplastic mesothelium, we felt it opportune to evaluate the use of TPA assay in 105 pleural effusions (46 benign and 59 malignant). The values were much higher than those found in blood. In hydrothorax the median value was 454 U/l (range, 59–1923), in exudative effusions 846 U/l (range, 258–4485), in metastatic pleural effusions 1277 U/l (range, 58–32352) and in mesotheliomas 7705 (range, 759–16000). The maximum value found in nonmalignant effusions was 4485 U/l; this value was taken as a cutoff level, so only 29.9 % of the tumors were positive to the test. Our results showed this assay to be not very important for a differential diagnosis of malignant and nonmalignant pleural effusions. Nevertheless, the different TPA patterns in mesotheliomas (66.6 % positive) and metastatic pleural effusions (15.9 %) suggest that further studies are warranted.

Evaluation of predictive value of pleural CEA in patients with pleural effusions and histological findings: A prospective study and literature review

OBJECTIVES

Pleural effusion recognizes heterogeneous etiology and pathogenesis and requires invasive diagnostic procedures. Usually, after pleural fluid analysis, 30-50% of patients with malignant pleural effusion exhibit negative pleural cytology, and the sensitivity of image-guided pleural needle-aspiration biopsy ranges between 60% and 70%. With the aim of differentiating between benign (BPE) and malignant (MPE) pleural effusions, several tumor markers have been assayed in the pleural fluid and the majority of studies focus on pleural carcinoembryonic antigen (p-CEA). The aims of this study were to evaluate (i) the diagnostic accuracy of p-CEA of patients with pleural effusions undergoing video-assisted thoracoscopic surgery (VATS) for diagnostic purpose, (ii) the relationship between p-CEA and serum CEA (s-CEA), and (iii) the usefulness of the p-CEA/s-CEA ratio in the diagnosis of malignant pleural effusions (MPE).

DESIGN & METHODS

We prospectively enrolled in the study 134 consecutive patients with pleural effusions, scheduled for having VATS and biopsy. The final diagnosis, based on histopathology of the VATS-guided specimens, was available for all patients. p-CEA and s-CEA was assayed with a chemiluminescence immunoassay method (CLIA), applied on the Maglumi 2000 Plus automated platform (SNIBE, Shenzen, China).

RESULTS

The sensitivity and accuracy of p-CEA was significantly higher than that of pleural cytology at the same specificity comparing BPE with MPE and BPE with non-small lung cancer. The sensitivity of p-CEA and PC together reached 100% (BPE vs. NSCLC) and 91.5% (BPE vs. MPE excluding mesothelioma), respectively.

CONCLUSIONS

The p-CEA measurement in patients with pleural effusion of uncertain etiology is a safe and cost-effective procedure, everywhere easily available, which may help clinicians in selecting patients for further evaluations. An elevated p-CEA level in a patient with pleural effusion and negative pleural cytology suggests the need of more invasive procedure (e.g. VATS-guided biopsies), whilst low p-CEA may support a follow-up.

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

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 tumor markers for differentiating malignant and benign pleural effusions of Iranian patients

In order to evaluate the diagnostic yield of tumor markers in differentiating malignant and benign pleural effusions, we carried out a prospective study in a group of Iranian people. Pleural and serum levels of carcinoembryonic antigen (CEA), carbohydrate antigen 15-3 (CA 15-3), neuron-specific enolase (NSE) and cancer antigen 125 (CA 125) were assayed prospectively in patients with pleural effusion (40 malignant and 37 benign). The highest sensitivity was obtained with a combination of CA 15-3 in serum, and CA 15-3 and CEA in pleural fluid (80%), also with combination of CA 15-3 in serum, and CA 15-3, NSE and CEA in pleural fluid (80%). The highest specificity was obtained with combination of CA 15-3 in serum, and CA 15-3 and NSE in pleural fluid (100%), and also with combination of CA 15-3 in serum, and CA15-3, NSE and CEA in pleural fluid (100%).

The implication of elevated carcinoembryonic antigen level in pleural fluid of patients with non-malignant pleural effusion

OBJECTIVE

The aim of this study was to evaluate the false positive rate for pleural fluid carcinoembryonic antigen (CEA) level in non-malignant pleural effusions and to determine whether the falsely elevated CEA level has any relation to other biochemical parameters of pleural effusions.

METHODOLOGY

We performed a retrospective analysis of 654 consecutive patients with a pleural effusion admitted to the pulmonary department of a tertiary referral teaching hospital from March 1997 to March 1999. The aetiology of the pleural effusions were classified as tuberculosis (n = 262), malignancy (n = 204), pneumonia (n = 145), exudates of other origin (n = 28) and transudate (n = 1).

RESULTS

A false positive result for pleural fluid CEA level (> 5 ng/mL) was registered in 13.8% of non-malignant pleural effusion cases: empyema (38.6%), parapneumonic effusion (14.7%), exudates of other origin (14.3%), tuberculosis (7.3%) and transudate (6.7%). In analysis of the subgroup with false positive results for pleural fluid CEA level, the CEA level of non-malignant pleural effusion showed a significant relationship to the severity of pleural inflammation in terms of the following variables: LDH (rs = 0.4201, P= 0.001), adenosine deaminase (ADA) (rs = 0.4440, P= 0.0004), white blood cell count (rs = 0.4266, P= 0.0004), polymorphonuclear cell percentage (rs = 0.5080, P= 0.0001), and polymorphonuclear cell count (rs = 0.5095, P= 0.0002). In the parapneumonic effusion and empyema groups, the changes in pleural fluid CEA level exhibited a positive association with the changes in the pleural fluid ADA level (rs = 0.8143, P= 0.0002).

CONCLUSIONS

The results from our series indicated that false positive results for pleural fluid CEA level were most commonly observed in patients with empyema and parapneumonic effusion and the CEA level showed a significant correlation to the indices of pleural inflammation. The serial measurement of pleural fluid CEA level may be useful as a means of monitoring resolution of pleural inflammation and excluding the possibility of a malignant pleural effusion.

Diagnostic value of C-reactive protein in exudative pleural effusions

BACKGROUND: Tests able to help in the diagnostic work-up of pleural exudates are needed. C-reactive protein (CRP) may be useful for distinguishing between benign and malignant exudates. METHODS: A total of 123 consecutive patients diagnosed as having exudative pleural effusion (60 associated with malignancy and 63 benign effusions) were included in the study. Sensitivity, specificity, positive and negative predictive values (PV+, PV-), and positive and negative likelihood ratios (LR+, LR-) were established at different cut-off points. RESULTS: Pleural fluid CRP level was 23+/-12 mg/l (mean+/-S.D.) in pleural exudates associated with malignancy and 50+/-33 mg/l in benign effusions (P<0.001). With a cut-off point below 20 mg/l for malignancy, sensitivity of CRP was 0.50, specificity 0.89, PV+ 0.81, PV- 0.65, LR+ 4.50, and LR- 0.65. With a cut-off point above 45 mg/l for benign diseases, sensitivity was 0.44, specificity 0.95, PV+ 0.90, PV- 0.62, LR+ 8.89, and LR- 0.58. CONCLUSIONS: The pleural CRP level provides useful information for the study of pleural exudates. A level below 20 mg/l suggests a malignant origin and a level above 45 mg/l virtually rules out this possibility. Additional advantages of measuring CRP level are that it is an inexpensive test and is easy to perform.

Elevated level of carcinoembryonic antigen in nonmalignant pleural effusions

STUDY OBJECTIVE

Carcinoembryonic antigen (CEA) is the most frequently used tumor marker in pleural fluid. Nevertheless, little is known about the causes of false-positive results. The aim of the study was to analyze the frequency, etiologies, and characteristics of the nonmalignant pleural effusions associated with elevated levels of CEA in pleural fluid.

PATIENTS

Two hundred seventy-three consecutive patients with pleural effusions were evaluated, 91 (33%) associated with malignancy, and 182 (67%) due to benign diseases (51 transudates, 38 tuberculosis, 37 parapneumonic, 56 other).

RESULTS

A level of CEA in pleural fluid above 10 ng/mL was found in 47% of pleural effusions associated with malignancy. Elevated levels of CEA were also found in 17 of the 182 (9%) nonmalignant pleural effusions: all five empyemas, one of the 23 typical parapneumonic (4%), two of the six borderline complicated (33%), and four of the eight complicated parapneumonic effusions (50%), one of the 38 tuberculous pleurisy (3%), one of the 11 hepatic transudates (9%), in the only patient with urinothorax, in the only patient with acute pancreatitis, and in one patient with postsurgery pleural effusion but with esophageal carcinoma and elevated CEA level in serum.

CONCLUSIONS

Although an elevated level of CEA in pleural fluid is suggestive of malignancy, CEA can be elevated in 9% of pleurisy owing to benign diseases, especially in empyemas and in complicated parapneumonic effusions. Identifying the most frequent causes of false-positive results of CEA helps to correctly interpret the findings of this tumor marker.

Carcinoembryonic antigen, tissue polypeptide antigen and neuron-specific enolase pleural levels used to classify small-cell and non-small-cell lung cancer patients by discriminant analysis

The classification of lung cancer into small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC) is essential for disease prognosis and treatment. For this purpose, we have tried to optimize the use of three tumour markers determined on pleural effusions, to differentiate SCLC from NSCLC by means of a canonic variable, generated by discriminant analysis, including subjects with histologically proven lung cancer. Discriminant analysis was performed by using carcinoembryonic antigen, neuron-specific enolase and tissue polypeptide antigen pleural levels, determined in 65 consecutive and unselected patients, histologically classified as 49 NSCLC and 16 SCLC. To validate the formula generated, a control group of 37 lung cancer patients (10 SCLC and 27 NSCLC), enrolled subsequently, was employed. Applying the discriminant analysis to SCLC and NSCLC patients a good classification was obtained (92% rate of correct classification). The aforementioned formula, applied to the validation group, showed a 92% rate of correct classification. This method, which is rapid, inexpensive and routinely applicable to malignant pleural effusions, may be reliably used to classify lung cancer patients.

Etiologic considerations of nonspecific pleuritis

Twenty-three patients with nonspecific pleuritis were studied to determine clinical outcome. After a mean follow-up period of 6 months (1 to 36 months), a diagnosis was reached in 17 patients, while 6 patients remained unknown. The causes of the nonspecific pleuritis diagnosed on initial pleural biopsy were tuberculosis (11 patients, 48%), neoplasm (2 patients, 8.7%), parapneumonic effusion (1 patient), subphrenic abscess (1 patient), congestive heart failure (1 patients), and nephrotic syndrome (1 patient). The diagnosis was made by therapeutic trials (tuberculosis: 11 patients, parapneumonic effusion: 1 patient, congestive heart failure: 1 patient), by repeat pleural biopsy in 1 hepatoma, by open thoractomy in 1 lung cancer, by exploratory laparotomy in 1 subphrenic abscess, and by kidney biopsy in 1 nephrotic syndrome. The WBC counts (more than 2,000/mm3) and lymphocyte percentage (more than 60%) in the pleural fluid were significantly elevated in the patients with tuberculosis compared to those with malignant pleurisy, and other laboratory data were meaningless. As a result of this investigation, we suggest that tuberculous pleurisy is the most common cause of nonspecific pleuritis in Korea and that therapeutic trial with antituberculous medication for patients with high WBC count and lymphocyte percent in pleural fluid can help to locate the nonspecific pleuritis.

Use of CA 125 monoclonal antibody to monitor patients with ovarian cancer

The monoclonal antibody (mAb) OC 125 reacts with an antigen on human ovarian carcinoma (OVCA) cells that is also shed into the body fluids and can be detected in patients' sera and/or ascites with a radioimmunometric assay. For the present study, serum CA 125 levels of patients (n = 36) with different stages of OVCA were investigated. Serum levels seem to correlate with tumor burden. In stages I and II (n = 12), 33% of patients were CA 125 positive, whereas 70% of stage III and IV patients (n = 24) were CA 125 positive. Mean serum levels were in 93 U/ml (stages I, II) and 279 U/ml (stages III, IV). CA 125 levels in ascites and in pleural effusions were manyfold higher than serum levels of the same patients (P less than 0.0001). Immunohistochemical investigations of CA 125 in different ovarian tumors (n = 91) revealed that 85% of malignant and 75% of borderline serous cystadenocarcinomas had detectable CA 125 surface expression. Furthermore, 71% of benign tumors showed the CA 125 epitope, whereas mucinous tumors were negative for this marker. One of six ovarian cancer cell lines was CA 125 positive, whereas in 6 of 11 patients, ascites-derived ovarian cancer cells (fresh and gradient isolated) were positive for this marker. The proportion of positive cells ranged from 10 to 90% in these samples. Intraperitoneal recombinant interferon-gamma (rIFN-gamma) therapy resulted in an increase in the number of cells reacting with CA 125. The results of monitoring in patients receiving different therapeutic regimens and/or agents demonstrate the usefulness of this marker.

Immunoradiometric assay of CA 125 in effusions. Comparison with carcinoembryonic antigen

The levels of CA 125 antigen were measured in 167 effusions from 150 patients using radioimmunoassay, and the results compared with the levels of carcinoembryonic antigen (CEA) in the fluids. This study was carried out to test a hypothesis that measuring the combined levels of selected tumor associated antigens in effusions could predict the primary source of malignancy. The results indicate that an elevated fluid CA 125 level (greater than 14,000 U/ml-68,000 U/ml) and a negative fluid CEA level (less than 5 ng/ml) is suggestive of serous and endometrioid carcinoma of ovary, and adenocarcinoma of the endometrium and fallopian tube. Alternatively, an elevated fluid CEA level (14 ng/ml-600 ng/ml) and a negative CA 125 level (20-5000 U/ml) is seen in metastatic carcinomas of breast, lung, gastrointestinal tract, and mucinous cystadenocarcinoma. Lymphomas, melanomas, and benign effusions are negative for both antigens. The combined use of CEA and CA 125 antigen in fluids is useful in the differential diagnosis of adenocarcinoma of unknown primary.

Diagnosis and treatment of malignant pleural effusion

Pleural effusion is a common and important complication of malignancy which may at times be difficult to diagnose or treat. Its well recognized association with numerous diseases plus the limitations of our usual diagnostic tests may occasionally cause difficulty. In the oncology patient there are a number of common medical problems associated with the development of pleural effusion which frequently coexist with the malignancy. Pleural effusion may be a presenting or late sign of cancer, and when recurrent can be a vexing symptomatic problem. Fortunately, an increasing number of effective diagnostic and therapeutic modalities are available which, when judiciously applied, facilitate our approach.

Carcinoembryonic antigen in pleural effusions. Diagnostic value in malignant mesothelioma

The usefulness of the determination of carcinoembryonic antigen (CEA) in pleural effusion was assessed as an aid to the diagnosis of malignant mesothelioma. The concentration of CEA was determined by radioimmunoassay (RIA) in pleural fluid of 213 adult patients, of which 140 had malignant pleural disease and 73 had nonmalignant pleural disease. Pleural fluid CEA (PF CEA) was lower than 12 ng/ml in all 15 mesotheliomas. The statistical probability of a mesothelioma associated with PF CEA greater than 15 ng/ml was found to be zero. The CEA assay in pleural effusion proved to be a valuable adjunct to other diagnostic procedures in differentiating the malignant mesothelioma from metastatic serosal spread.

The diagnosis of pleural effusions--are cancer markers clinically helpful?

We submitted 83 consecutive patients with pleural effusion to routine clinical investigation; 57 were diagnosed as malignant, 18 as benign, and 8 were not diagnosed. Pleural fluid and serum were analysed for carcinoembryonic antigen (CEA), acid glycoprotein (AGP), antichymotrypsin (ACT), C-reactive protein (CRP), alpha 2-pregnancy associated glycoprotein (alpha 2-PAG) and ferritin. Multivariate discriminant analysis was performed on the results of the protein measurements. CEA and ACT values in serum and fluid were found to give a good discriminating function between the benign and malignant groups. The use of such an analysis, in a clinical context, is discussed.