Clinical evaluation of the simultaneous determination of tumor markers in fluid and serum and their ratio in the differential diagnosis of serous effusions

Differential diagnosis of ascites: etiologies, ascitic fluid analysis, diagnostic algorithm

Ascites is the pathological accumulation of fluid within the peritoneal cavity. It often occurs as results of liver cirrhosis, malignant neoplasia, tuberculous infection, cardiac insufficiency, renal diseases, etc. Determining the etiology is an essential step in the management of patients with new-onset ascites. Abdominal paracentesis with appropriate ascitic fluid analysis is probably the most cost-effective method of determining the cause of ascites. We performed a literature search of PubMed and identified articles published in the field of ascites, to evaluate diagnostic values of various parameters in defining the etiologies of ascites and then provides diagnostic algorithm for patients with new-onset ascites. In patients with ascites, the constituent ratio of underlying etiology varies between developed and developing countries. It is a challenge to define the etiologies of ascites in developing countries. Routine ascitic fluid analysis should include the serum ascites albumin gradient (SAAG), total protein concentration, cell count and differential. Optional ascitic fluid analysis includes cholesterol, fluid culture, cytology, tumor markers, lactate dehydrogenase, adenosine deaminase (ADA), triglyceride, amylase, glucose, brain natriuretic peptide (BNP), etc. Our review evaluated diagnostic values of the above parameters in defining the etiologies of ascites. Diagnostic algorithm established in this review would provide a practical and convenient diagnostic strategy for clinicians in diagnosing patients with new-onset ascites.

Lung cancer tumor markers in serous effusions and other body fluids

From its onset and during its progression, lung cancer may affect various extrapulmonary structures. These include the serous membranes, the pleura and pericardium, and less frequently the central nervous system, with leptomeningeal involvement. In these cases, fluid accumulates in the serous membranes which may contain substances secreted by the tumor. Measuring the concentrations of these substances can provide useful information for elucidating the origin of the fluid accumulation, either in pleural and pericardial effusions or in cerebrospinal fluid. This paper describes the histological types of lung cancer that most frequently affect the serosa and leptomeninges. It also reviews the literature on tumor markers in different fluids and makes recommendations for their interpretation.

Factors influencing blood tumor marker concentrations in the absence of neoplasia

BACKGROUND

Tumor markers (TMs) are a heterogeneous group of molecules used in the diagnosis, prognosis and follow-up of cancer patients. During neoplastic differentiation, cells can either directly synthesize or induce the synthesis of TMs, and the release of these molecules into the bloodstream allows their quantification in biological fluids. Although very small concentrations of TMs are usually present in the serum or plasma of healthy subjects, increased concentrations may also be found in the presence of benign diseases or due to technical interference, producing false positive results.

MATERIAL AND METHODS AND RESULTS

Our review analyses the causes of false positives described between January 1970 to February 2023 for the TMs most frequently used in clinical practice: α-fetoprotein (AFP), β2-microglobulin (β2-M), cancer antigen 15-3 (CA 15-3), cancer antigen CA 19-9 (CA 19-9), cancer antigen CA 72-4 (CA 72-4), cancer antigen 125 (CA 125), carcinoembryonic antigen (CEA), chromogranin A (CgA), choriogonadotropin (hCG), cytokeratin 19 fragment (CYFRA 21-1), neuron-specific enolase (NSE), human epididymis protein 4 (HE4), serum HER2 (sHER2), squamous cell carcinoma antigen (SCCA), protein induced by vitamin K absence-II (PIVKA-II), Pro-gastrin-releasing peptide (Pro-GRP), prostate-specific antigen (PSA), Protein S-100 (S-100) and thyroglobulin (Tg). A total of 247 references were included.

CONCLUSIONS

A better understanding of pathophysiological processes and other conditions that affect the concentration of TMs might improve the interpretation of results and their clinical application.

Diagnosis of malignant versus tuberculous ascites using tumor markers and globulin ratios in serum and ascites: A Fisher discriminant model

BACKGROUND AND STUDY AIMS

This study was conducted to investigate the significance of tumor and biochemical markers in serum and ascitic fluid in the differential diagnosis of tuberculous and malignant ascites.

PATIENTS AND METHODS

Based on findings from natural orifice transluminal endoscopic surgery and postoperative pathology or cytology of 63 patients, they were divided into the malignant group (31 patients) and the tuberculous group (32 patients). Levels of tumor markers, albumin, globulin, and lactate dehydrogenase were measured simultaneously. Data were statistically analyzed, and a Fisher discriminant model was established. The receiver operating characteristic curve was constructed to confirm the discriminant value.

RESULTS

The levels of carcinoembryonic antigen (CEA), cancer antigen 125 (CA125), cancer antigen 19-9 (CA 19-9), and globulin in serum and ascitic fluid were different between the tuberculous and malignant ascites groups (P < .05). The ratios of ascites-to-serum levels of CEA, CA125, and CA 19-9, as well as the ratio of serum-to-ascites of globulin levels, were different between the two groups (P < .05). The Fisher discriminant model was established based on the ascites-to-serum ratios of CEA, CA125, and CA 19-9 levels and the serum-to-ascites ratio of globulin levels. The area under the curve was 0.908, the sensitivity was 0.838 (26/31), and the specificity was 0.875 (28/32).

CONCLUSION

A Fisher discriminant model can be established using serum and ascites tumor markers and globulin ratios, which is valuable in the differential diagnosis of tuberculous versus malignant ascites.

Comparative Assessment of Two Strategies for Interpreting Tumor Markers in Ascitic Effusions

BACKGROUND/AIM

There are two strategies for the interpretation of tumor markers (TM) in fluid effusions: i) high cut-off and ii) fluid/serum ratio (F/S) and low cut-off. The objective of this study is to compare these two strategies and to determine whether diagnostic accuracy improves by the identification of possible false positives using Adenosine deaminase (ADA), C reactive protein (CRP) and % of polymorphonuclear cells (%PN).

PATIENTS AND METHODS

We studied 157 ascitic fluids, 74 of which were malignant. ADA, CRP and %PN were determined in ascitic fluid, and Carcinoembryonic antigen (CEA), Cancer antigen 72-4 (CA72-4), Cancer antigen CA19-9 and Cancer antigen 15-3 (CA15-3) in both fluid and serum.

RESULTS

The strategy of high cut-off showed 59.5% sensitivity at 100% specificity. The F/S strategy showed 75.7% sensitivity at 95.2% specificity. Subclassifying cases with ADA, CRP and %PN negative showed 67.5% sensitivity at 100% specificity for high cut-off and for the F/S strategy was 81.7% sensitivity at 98.7% specificity.

CONCLUSION

The strategy of F/S with negative ADA, CRP and %PN allow the best interpretation for TM in the ascitic fluid.

The clinical utility of joined detection of cancer ratio, cancer ratio plus, Interferon gamma (IFN-ϒ) & Carcinoembryonic antigen (CEA) in differentiating lymphocytic pleural effusions

Background

The differentiation between malignant (MPE) and tuberculous (TPE) pleural effusions should be considered in any patient with an exudative lymphocytic pleural effusion. A rapid precise diagnosis is valuable as the treatment and prognosis are totally different. The histopathological proof may shorten the time to differential diagnosis. But it may be invasive and costly. The aim of this study is to validate the clinical reliability of joined detection of cancer ratio (serum LDH to pleural ADA), cancer ratio plus (cancer ratio to percentage of pleural fluid lymphocytic count), pleural interferon gamma (pIFN-ϒ), and pleural carcinoembryonic antigen (pCEA) values to differentiate between lymphocytic pleural effusions.

Results

Seventy-eight patients were included with mean age ± SD 53.09 ± 9.56 years old, 49 males and 29 females, diagnosed as 47 MPE, 24 TPE, and 7 others. Cancer ratio at cutoff value of ≥ 22 and cancer ration plus at cutoff value of ≥ 41 can discriminate MPE from any other cause with sensitivity (91.5%, 93.6%), specificity (87.5%, 91.7%), and diagnostic accuracy (90.1%, 92.9%) respectively. When the levels of pCEA and pIFN-ϒ were combined with cutoff value of cancer ratio, there were powerful diagnostic differentiating results.

Conclusions

Cancer ratio and cancer ratio plus offered valid, efficient, non-invasive, and easy measuring diagnostic tools. On diagnostic uncertainty, the add-on of pCEA in cases of suspected MPE, and pIFN-ϒ in cases of suspected TPE has a trustable diagnostic efficacy with no need for further investigations.

The diagnostic value of pleural fluid homocysteine in malignant pleural effusion

Background

Pleural fluid homocysteine (HCY) can be useful for diagnosis of malignant pleural effusion (MPE). There are no published studies comparing the diagnostic accuracy of HCY with other tumour markers in pleural fluid for diagnosis of MPE. The aim was to compare the accuracy of HCY with that of carcinoembryonic antigen (CEA), cancer antigen (CA) 15.3, CA19.9 and CA125 in pleural fluid and to develop a probabilistic model using these biomarkers to differentiate benign (BPE) from MPE.

Methods

Patients with pleural effusion were randomly included. HCY, CEA, CA15.3, CEA19.9 and CA125 were quantified in pleural fluid. Patients were classified into two groups: MPE or BPE. By applying logistic regression analysis, a multivariate probabilistic model was developed using pleural fluid biomarkers. The diagnostic accuracy was determined by receiver operating characteristic (ROC) curves and calculating the area under the curve (AUC).

Results

Population of study comprised 133 patients (72 males and 61 females) aged between 1 and 96 years (median = 70 years), 81 BPE and 52 MPE. The logistic regression analysis included HCY (p<0.0001) and CEA (p = 0.0022) in the probabilistic model and excluded the other tumour markers. The probabilistic model was: HCY+CEA = Probability(%) = 100×(1+e^-z)^-1, where Z = 0.5471×[HCY]+0.3846×[CEA]–8.2671. The AUCs were 0.606, 0.703, 0.778, 0.800, 0.846 and 0.948 for CA125, CA19.9, CEA, CA15.3, HCY and HCY+CEA, respectively.

Conclusions

Pleural fluid HCY has higher accuracy for diagnosis of MPE than CEA, CA15.3, CA19.9 and CA125. The combination of HCY and CEA concentrations in pleural fluid significantly improves the diagnostic accuracy of the test.

Ratio of carcinoembryonic antigen in pleural fluid and serum for the diagnosis of malignant pleural effusion

Background

Tumour markers in pleural fluid and their diagnostic value are subject to debate. Although there are several studies on this topic, standardized cut-off values do not exist. In this study we investigated the potential of a ratio of carcinoembryonic antigen (CEA) in pleural fluid and serum, serving as an individual marker for pleural cancer manifestation.

Methods

A total of 201 consecutive patients with unclear pleural effusion were included in the study; 98 were diagnosed with malignant pleural effusion and 103 had an effusion due to other, benign reasons. CEA levels in pleural fluid and serum were measured.

Results

By using receiver operating characteristics analysis, at the cut-off of 1.0, the CEA ratio showed a specificity of 92% and sensitivity of 85%, with a positive predictive value of 91% and a negative predictive value of 87%. These results are higher than in previous investigations on different pleural tumour markers and their combination.

Conclusions

The CEA ratio is a useful tool in predicting pleural carcinosis. Elevated results in cytology-negative patients should lead to further investigations, such as repeated cytological examination or thoracoscopy.

Clinical Value of Positron Emission Tomography-Computed Tomography Combined with Ultrasound in Detection of Primary Tumors in Patients with Malignant Ascites

OBJECTIVE

To investigate and discuss the clinical value of positron emission tomography-computed tomography (PET-CT) combined with ultrasound in detection of primary tumors in patients with malignant ascites (MA).

MATERIALS AND METHODS

A total of 122 malignant tumor patients with ascites as the initial symptom and 48 patients with benign ascites were enrolled in this study. All patients underwent PET-CT and abdominal B-ultrasound examinations. The corresponding specificity, sensitivity, accuracy rate, positive predictive value, and negative predictive value of PET-CT, abdominal B-ultrasound, and combined detection group were recorded, respectively, with pathological findings as the gold standards. Statistical Product and Service Solutions 17.0 software was used for statistical analysis. p < 0.05 suggested that the difference was statistically significant.

RESULTS

The detection rate of primary foci through PET-CT was 79.5%, of which the detection rate of primary foci of MA derived from gastric cancer was the highest. The detection rate of primary foci through B-ultrasound was 62.5%, which is the highest for MA derived from ovarian cancer. B-ultrasound had the highest specificity in diagnosing the primary foci of MA (73.2%), PET-CT had the highest sensitivity in diagnosing the primary foci of MA (91.7%), and PET-CT combined with abdominal B-ultrasound had the highest sensitivity and accuracy in diagnosing the primary foci of MA (98.1% and 89.1%, respectively). The diagnostic accuracy rate of B-ultrasound was the highest in detecting tumors >5 cm (77.0%), whereas that of PET-CT was the highest in detecting tumors of 3-5 cm (84.2%).

CONCLUSION

The PET-CT combined with ultrasound is conducive to improving the diagnostic efficiency for primary tumors in patients with MA.

Value of 18F-FDG PET/CT Combined With Tumor Markers in the Evaluation of Ascites

OBJECTIVE

The purpose of this study is to investigate the value of ¹⁸F-FDG PET/CT combined with assessment of tumor markers in serum or ascites for the diagnosing and determining the prognosis of benign and malignant ascites.

MATERIALS AND METHODS

Patients with ascites of unknown cause who underwent evaluation with FDG PET/CT were included in this retrospective study. The maximum standardized uptake value (SUV_max) and levels of the tumor markers carbohydrate antigen-125 (CA-125) and carcinoembryonic antigen (CEA) in serum and ascites were recorded. The diagnostic values of FDG PET/CT, CEA and CA-125 levels in serum or ascites, and the combination of imaging plus tumor marker assessment were evaluated. Factors that were predictive of survival were also analyzed.

RESULTS

A total of 177 patients were included. Malignant ascites was eventually diagnosed in 104 patients, and benign ascites was diagnosed in the remaining 73 patients. With the use of FDG PET/CT, 44 patients (42.3%) were found to have primary tumors. The sensitivity, specificity, and accuracy of FDG PET/CT were 92.3%, 83.6%, and 88.7%, respectively. CA-125 levels in serum and ascites showed much better sensitivity than did CEA levels, but they showed significantly lower specificity. If the combination of tumor markers and FDG PET/CT was analyzed, the sensitivity, specificity, and accuracy of tumor markers in serum were 96.6%, 78.1%, and 88.7%, and those of tumor markers in ascites were 97.7%, 80.0%, and 90.4%, respectively. Sex may be an important factor affecting survival time (hazard ratio, 0.471; p = 0.004), but age, CEA level, and FDG PET/CT findings could not predict survival.

CONCLUSION

FDG PET/CT combined with assessment of tumor markers, especially CEA, increased the efficacy of diagnosis of ascites of unknown causes. Male sex conferred a poorer prognosis, whereas age, CEA level, and FDG uptake had no predictive significance in patients with malignant ascites.

Diagnostic accuracy of tumor markers for malignant pleural effusion: a derivation and validation study

Background

The utility of tumor markers (TMs) for differentiating malignant pleural effusion (MPE) from benign pleural effusion (BPE) has been a subject of controversy. The majority of published studies are single center designed and lack validation. We performed a derivation and validation study in China to evaluate the diagnostic value of carcinoembryonic antigen (CEA) as well as carbohydrate antigen (CA) 15-3, CA 19-9 and CA 125 to differentiate between MPE and BPE.

Methods

Three hundred and twenty seven pleural effusion (PE) and paired serum samples were collected from consecutive patients with MPE or BPE in Beijing (174 patients, derivation) and Wuhan (153 patients, validation) during the same period. The concentrations of four TMs were tested using chemiluminescent microparticle immunoassay technology. The performance of the TMs was analyzed by standard receiver operating characteristic (ROC) curves.

Results

The levels of four TMs were significantly higher in MPE than in BPE and the corresponding serum. The concentrations of CEA and CA 15-3 were more stable than the concentrations of CA 125 and CA 19-9. CEA was the best single marker for discriminating MPE from BPE. With a specificity of 100% in the total population, the highest sensitivity (37.8%) using serum was found in CEA. In addition, CEA presented 19.8% sensitivity in PE and 18.0% sensitivity in the Δ(PE-serum). For CA 15-3, the sensitivity was 32.4% in PE, 15.3% in the PE/serum ratio and 25.2% in the Δ(PE-serum).

Conclusions

CEA and CA 15-3 rather than CA 125 and CA 19-9 are more reliable to differentiate between MPE and BPE. The use of the Δ(PE-serum) value in TMs, such as CEA and CA 15-3, may improve the sensitivity and specificity of the diagnosis etiology of PE.

Reference limits for chromogranin A, CYFRA 21-1, CA 125, CA 19-9 and carcinoembryonic antigen in patients with chronic kidney disease

BACKGROUND

Patients with chronic kidney disease (CKD) may have increased plasma concentrations of some tumor markers even when no cancer is present. Previous studies have indicated that plasma concentrations of chromogranin A (CGA), cytokeratin 19 fragments (CYFRA 21-1), cancer antigen 125 (CA 125), cancer antigen 19-9 (CA 19-9) and carcinoembryonic antigen (CEA) are higher in patients with CKD but without cancer, than in healthy individuals, and this can make interpretation of results more complicated. The aim of this study was to establish reference limits for these markers in patients with CKD not receiving dialysis and with no clinical evidence of cancer.

METHODS

We measured plasma concentrations in samples from 131 patients with CKD due to various etiologies and studied the association of tumor marker concentrations with estimated glomerular filtration rate (GFR) and other patient characteristics.

RESULTS

Estimated reference limits for plasma CA 125, CA 19-9 and CEA were approximately the same as for healthy populations. Serum concentrations of CGA and CYFRA 21-1 correlated strongly with estimated GFR, and GFR-dependent reference limits were estimated.

CONCLUSIONS

GFR-dependent reference limits for CGA and CYFRA 21-1 are reported in order to support interpretation of these markers in patients with CKD.

Evaluation of two strategies for the interpretation of tumour markers in pleural effusions

Background

Pleural effusions present a diagnostic challenge. Approximately 20% are associated with cancer and some 50% require invasive procedures to perform diagnosis. Determination of tumour markers may help to identify patients with malignant effusions. Two strategies are used to obtain high specificity in the differential diagnosis of malignant pleural effusions: a) high cut-off, and b) fluid/serum (F/S) ratio and low cut-off. The aim of this study is to compare these two strategies and to establish whether the identification of possible false positives using benign biomarkers – ADA, CRP and % of polymorphonuclear cells – improves diagnostic accuracy.

Methods

We studied 402 pleural effusions, 122 of them malignant. Benign biomarkers were determined in pleural fluid, and CEA, CA72-4, CA19-9 and CA15-3 in pleural fluid and serum.

Results

Establishing a cut-off value for each TM for a specificity of 100%, a joint sensitivity of 66.5% was obtained. With the F/S strategy and low cut-off points, sensitivity was 77% and specificity 98.2%, Subclassifying cases with negative benign biomarkers, both strategies achieved a specificity of 100%; sensitivity was 69.9% for single determination and 80.6% for F/S ratio.

Conclusions

The best interpretation of TM in the differential diagnosis of malignant pleural effusions is obtained using the F/S ratio in the group with negative benign biomarkers.

Clinical value of jointly detection serum lactate dehydrogenase/pleural fluid adenosine deaminase and pleural fluid carcinoembryonic antigen in the identification of malignant pleural effusion

BACKGROUND

Limited data are available for the diagnostic value, and for the diagnostic sensitivity and specificity of joint detection of serum lactate dehydrogenase (sLDH)/pleural fluid adenosine deaminase (pADA) and pleural fluid carcinoembryonic antigen (pCEA) in malignant pleural effusion (MPE).

METHODS

We collected 987 pleural effusion specimens (of which 318 were malignant pleural effusion, 374 were tubercular pleural effusion, and 295 were parapneumonic effusion specimens) from the First Affiliated Hospital of Wenzhou Medical University from July 2012 to March 2016. The pADA, sLDH, pleural fluid LDH (pLDH), serum C-reactive protein (sCRP), pleural fluid protein, pCEA, white blood cell (WBC), and red blood cell (RBC) were analyzed, and the clinical data of each group were collected for statistical analysis.

RESULTS

The level of sLDH/pADA, pCEA, and RBC from the MPE group was markedly higher than the tuberculosis pleural effusion (TB) group (Mann-Whitney U=28422.000, 9278.000, 30518, P=.000, .000, .000) and the parapneumonic pleural fluid group (Mann-Whitney U=5972.500, 7113.000, 36750.500, P=.000, .000, .000). The receiver operating characteristic curve ROC showed that the area under the ROC curve (AUC) (=0.924, 0.841) of pCEA and sLDH/pADA (cutoff=4.9, 10.6) were significantly higher than other markers for the diagnosis of MPE. Thus, joint detection of pCEA and sLDH/pADA suggested that the sensitivity, specificity, and AUC was 0.94, 81.70, and 94.32 at the cutoff 0.16 and diagnostic performance was higher than pCEA or sLDH/pADA.

CONCLUSION

Joint detection of sLDH/pADA and pCEA can be used as a good indicator for the identification of benign and MPE with higher sensitivity and specificity than pCEA or sLDH/pADA.

Value of measurement of gradient and ratio of ascites-serum tumor markers in differential diagnosis of tuberculous ascites and malignant ascites

AIM

To assess the value of measurement of the gradient and ratio of ascites-serum tumor markers in the differential diagnosis of tuberculous ascites and malignancy-related ascites.

METHODS

Sixty patients with ascites were divided into two groups, namely, 31 cases of malignant ascites and 31 cases of tuberculous ascites. Tumor markers in serum and ascites were simultaneously detected to calculate and compare the gradient and ratio of serum-ascites tumor markers between the two groups.

RESULTS

The positive rates of CEA and CA199 in the malignant group were significantly higher than those of the tuberculosis group (P < 0.01). The positive rates of CA125 and α-fetoprotein (AFP) showed no significant difference between the two groups (P > 0.05). Ratio analysis of tumor markers in ascites and serum revealed that CA125, CA199, and CEA ratios were statistically significant between the two groups, with CA125 ratio having the most significant difference (P < 0.01). Ascites-serum gradient analysis showed that CA125, CEA, and CA199 gradients were significantly different between the two groups (P < 0.01). The ratio and gradient of AFP were not significantly different between the two groups (P > 0.05).

CONCLUSION

At the cutoff values of CA125 ratio > 2.16, CA125 gradient > 264.05 ng/mL, CEA ratio > 4.8, CEA gradient > 23.05 ng/mL, CA199 ratio > 0.96, and CEA gradient > -0.20 ng/mL, the diagnostic value of combining the gradients and ratios of the three tumor markers are more helpful to distinguish tuberculous ascites and non-liver cancer ascites than any of the three markers alone.

Tumor markers in serum and ascites in the diagnosis of benign and malignant ascites

OBJECTIVE

To evaluate the values of 4 tumor markers in serum and ascites and their ascites/serum ratios in the identification and diagnosis of benign and malignant ascites.

MATERIALS AND METHODS

A total of 76 patients were selected as subjects and divided into malignant ascites group (45 cases) and benign ascites group (31 cases). Samples of ascites and serum of all hospitalized patients were collected before treatment. The levels of carcinoembryonic antigen (CEA), alpha fetoprotein (AFP), cancer antigen 125 (CA125) and carbohydrate antigen 19-9 (CA19-9) were detected by chemiluminescence (CLIA) .

RESULTS

CEA, AFP and CA19-9 in both serum and ascites as well as CA125 in ascites were evidently higher in the malignant ascites group than in the benign ascites group (P<0.01). Malignant ascites was associated with elevated ascites/serum ratios for AFP and CA125 (P<0.01). The areas under receiver operating characteristic (AUROCs) of CEA and CA125 in ascites and the ratios of ascites/serum of AFP, CEA, CA125 and CA19-9 were all >0.7, suggesting certain values, while those of ascites CA19-9 and serum CEA were 0.697 and 0.629 respectively, indicating low accuracy in the identification and diagnosis of benign and malignant ascites. However, the AUROCs of the remaining indexes were <0.5, with no value for identification and diagnosis. Compared with single index, the sensitivity of combined detection increased significantly (P<0.05), in which the combined detection of CEA, CA19-9 and CA125 in ascites as well as the ratio of ascites/serum of CEA, CA19-9, CA125 and AFP had the highest sensitivity (98.4%) but with relevantly low specificity. Both sensitivity and specificity of combined detection should be comprehensively considered so as to choose the most appropriate index.

CONCLUSIONS

Compared with single index, combined detection of tumor markers in serum and ascites can significantly improve the diagnostic sensitivity and specificity.

Homocysteine: new tumor marker in pleural fluid

There are no published studies examining the utility of total homocysteine (HCY) in pleural fluid. The aim was to measure the accuracy of pleural fluid HCY concentration for diagnosis of malignant pleural effusion (MPE). We studied pleural fluids obtained by thoracocentesis in patients with pleural effusion. Pleural fluid HCY concentration was measured by immunonephelometry using N Latex HCY reagent with monoclonal antibody in automated analyzers BNII (Siemens Diagnostics®). Patients were classified into two groups according to the etiology of pleural effusion: benign pleural effusions (BPE) and MPE. Pleural effusion was categorized as MPE if malignant cells were demonstrated in pleural fluid or pleural biopsy. The accuracy of pleural fluid HCY concentration for diagnosis of MPE was determined using receiver operating characteristic (ROC) techniques by analyzing the area under the ROC curve (AUC). We studied 89 patients with ages between 1 and 96 years old (median = 66). Forty-eight patients were BPE and 41 were MPE. Pleural fluid HCY concentration was significantly higher in patients with MPE (median = 13.70 μmol/L) than in those with BPE (median = 8.05 μmol/L). The AUC value was 0.833 (95 % confidence interval (CI) 0.739-0.903). The optimal cutoff value was 13.1 μmol/L exhibiting 56.1 % (95 % CI 39.8-71.5) sensitivity and 85.4 % (95 % CI 72.2-93.9) specificity. Pleural fluid HCY concentration showed high diagnostic accuracy to predict whether a pleural effusion is benign or malignant. Pleural fluid HCY concentration may be measured easily and quickly in automated analyzers and could be a tumor marker commonly used for diagnosis of MPE.

Evaluation of tumor markers carcinoembryonic antigen, cytokeratin 19 fragment and cancer-associated antigen 72-4 in neoplastic and non-neoplastic canine effusions differentiation

The concentration of tumor markers in body fluids can be used for diagnosis and prognosis of patients. This study aimed to investigate the performance of tumor markers cytokeratin 19 fragment (CYFRA 21-1), cancer-associated antigen 72-4 (CA 72-4) and carcinoembryonic antigen (CEA) in the neoplastic and non-neoplastic canine effusions. In thirty-two neoplastic (n=16) and non-neoplastic (n=16) samples of canine thoracic or abdominal effusions, tumor markers were measured. Significant statistical difference was found only for the CYFRA 21-1 marker. The levels were significantly higher for the neoplastic group. The lack of significance between groups for markers CA 72-4 and CEA can be explained by the presence of other diseases in the non-neoplastic group, causing elevated levels of these markers. This study concludes that CYFRA 21-1 performed well, showing good sensitivity, specificity and accuracy in the diagnosis of neoplastic effusions in dogs. However, further investigations are necessary in patients with malignancy as those with benign effusions.

The diagnostic value of apolipoprotein E in malignant pleural effusion associated with non-small cell lung cancer

BACKGROUND

Apolipoprotein E (apoE) levels have been shown to be elevated in pleural effusion of patients with non-small cell lung cancer (NSCLC). However, the diagnostic value of apoE in pleural effusion in NSCLC has not been well validated and established.

METHODS

Samples of malignant pleural effusions (MPE) and benign effusions were collected and analyzed for apoE, tumor markers, and other biochemical changes.

RESULTS

ApoE levels were significantly higher in MPE (n=160) than in benign pleural effusions (n=40). They were higher in adenocarcinoma-associated MPE than in squamous cell carcinoma- and large cell carcinoma-associated MPE. The receiver operating characteristic curve showed that the sensitivity and specificity of apoE for the diagnosis of MPE were 87.5% and 85.3%, respectively, at the cutoff 105 ng/ml, and the area under the curve (AUC) was 0.748. For the diagnosis of adenocarcinoma-associated MPE, apoE achieved sensitivity and specificity of 70.8% and 83.30%, respectively, and the AUC was the highest of all the markers.

CONCLUSIONS

ApoE levels are significantly increased in the pleural effusion of patients with NSCLC. Increased concentration of apoE in a pleural effusion is a potential marker for the diagnosis of MPE as well as for differential diagnosis of MPE in NSCLC.

Diagnostic value of tumor markers in lung adenocarcinoma-associated cytologically negative pleural effusions

BACKGROUND

Cytology fails to detect neoplastic cells in approximately 40% to 50% of malignant pleural effusions (PEs), which commonly accompany lung adenocarcinomas. The diagnostic accuracy of various tumor markers in lung adenocarcinoma-associated cytologically negative pleural effusions (LAC-CNPEs) has been poor. The current study attempted to maximize diagnostic efforts in distinguishing LAC-CNPEs from benign PEs.

METHODS

PE samples were collected from 74 patients with lung adenocarcinoma with associated cytologically positive (41 patients) and negative (33 patients) PEs, and from 99 patients with benign conditions including tuberculosis (26 patients), pneumonia (28 patients), congestive heart failure (25 patients), and cirrhosis (20 patients). The authors evaluated the diagnostic sensitivity and optimal cutoff points for the tumor markers HER2/neu, CYFRA 21-1, and carcinoembryonic antigen (CEA) to distinguish LAC-CNPEs from benign PEs.

RESULTS

Mean levels of HER2/neu, CYRFA 21-1, and CEA were found to be significantly higher in LAC-CNPEs compared with benign PEs (P = .0050, P = .0039, and P < .0001, respectively). The cutoff points for HER2/neu, CYFRA 21-1, and CEA were optimally set at 3.6 ng/mL, 60 ng/mL, and 6.0 ng/mL, respectively. Their sensitivities ranged from 12.1%, to 30.3%, to 63.6%, respectively. CEA combined with CYFRA 21-1 increased diagnostic sensitivity to 66.7%. The false-positive rates of these markers in benign PEs were 6.1%, 2.0%, and 0%, respectively.

CONCLUSIONS

The combination of CEA with CYFRA 21-1 appears to provide the best differentiation between LAC-CNPEs and benign PEs to date using 2 tumor markers, and allows for the early diagnosis and early treatment of approximately two-thirds of affected patients.

Plasma concentrations of the vitamin E-binding protein afamin are associated with overall and progression-free survival and platinum sensitivity in serous ovarian cancer--a study by the OVCAD consortium

OBJECTIVE

Comparative proteomics identified the plasma protein afamin as potential biomarker for ovarian cancer (OC). Significantly decreased afamin plasma concentrations in pre-therapeutic OC patients reconstituted to control values after successful tumor surgery. This study evaluates the association of afamin with survival and response to therapy in serous OC patients within the OVCAD consortium project.

METHODS

We measured afamin in 215 pre-therapeutic plasma samples, 246 tumor lysates and 109 plasma samples taken 6months after finishing platinum-based chemotherapy. Differences in afamin plasma concentrations among FIGO stages were tested by Kruskal-Wallis test; association of afamin concentrations with overall and progression-free survival was evaluated using Kaplan-Meier survival plots and multivariate adjusted COX regression analysis.

RESULTS

Pre-therapeutic afamin correlated significantly with FIGO stages (p=0.012) and was lower in the presence of metastases (p=0.013) and poorly differentiated OC in patients responding to therapy (p=0.016). Afamin ≥48.0mg/L was also associated with a lower hazard ratio for recurrent disease as compared to afamin <48.0mg/L (p=0.007). Post-therapeutic afamin ≥48mg/L was positively correlated with overall (p<0.001) and progression-free (p=0.012) survival and was lower in non-responders than in responders (p=0.048). Thus, afamin returned post-therapeutically to values of healthy controls in responders (p<0.001) but not in non-responders (p=0.114). Afamin in tumor lysates was lower in poorly differentiated OC than in G 1+2 tumors (p=0.041). Higher afamin concentrations in tumor lysates were associated with increased overall survival (p=0.003).

CONCLUSION

These data indicate that afamin is associated with therapy response and survival rate in advanced OC patients.

Evaluation of pleural fluid human epididymis 4 (HE4) as a marker of malignant pleural effusion

Pleural effusion is a commonly encountered problem in clinical practice, and pleural fluid analysis is usually the first step towards identifying the underlying etiology. Numerous studies have been published analyzing the potential utility of measuring biomarkers in pleural fluid as possible indicators of a malignant effusion; however, there are no studies that have examined the presence of human epididymis 4 (HE4) in pleural effusions. The aims of this study were to assess pleural effusion and serum concentrations of HE4 in patients with different types of pleural effusions and to evaluate the diagnostic performance of HE4 in detecting malignant pleural effusion. A prospective cohort study was carried out of 88 consecutive patients presenting with pleural effusions. The patients were divided into three groups: 22 patients with transudative effusions, 32 patients with non-malignant exudative effusions, and 34 patients with malignant pleural effusions. Blood and pleural fluid HE4 levels were measured using immunoassay. Both serum HE4 levels and pleural effusion HE4 levels were significantly higher in patients with malignant effusions than in patients with transudative or non-malignant exudative effusions. A pleural fluid HE4 cutoff value of 1,675 pmol/L was found to predict malignant pleural effusions with a diagnostic sensitivity of 85.3 % and specificity of 90.7 %. The current study reports a novel finding of increased serum and pleural fluid HE4 levels in patients with malignant effusions compared to non-malignant effusions. This finding has the potential to strengthen the diagnostic performance of tumor markers in detecting malignant pleural effusions.

Diagnostic accuracy of tumour markers in serous effusions: a validation study

The utility of tumour markers (TM) in the differential diagnosis of cancer in serous effusion (fluid effusion (FE)) has been the subject of controversy. The aim of this study was to prospectively validate our previous study and to assess whether the addition of adenosine deaminase (ADA), C-reactive protein (CRP) or percentage of polymorphonuclear cells (%PN) allows the identification of false positives. In this study, carcinoembryonic antigen, cancer antigen 15-3, cancer antigen 19-9, ADA, CRP and %PN in FE were determined in 347 patients with 391 effusions. Effusions were considered as malignant effusion when at least one TM in serum exceeded the cutoff and the ratio FE/S was higher than 1.2. Also, cases with values of ADA, CRP and %PN above the established cutoffs in serous effusion were considered as potential false positives. The combined sensitivity and specificity of the three TM was 76.2 % (95 % confidence intervals (CI) 67.8-83.3 %) and 97.0 % (95 % CI 94.1-98.7), respectively. Subanalysis of the 318 cases with previous criteria and negative ADA, CRP and %PN obtained sensitivities of 78.4 % (95 % CI 69.4-85.6) and a specificity of 100 % (95 % CI 98.2-100). The results obtained validate our previous study and are improved with the addition of ADA, CRP and %PN. TM in serous effusions and serum could be useful for the diagnostic assessment of patients with serous effusions.

Expression of CA125 and cisplatin susceptibility of pleural effusion-derived human lung cancer cells from a Thai patient

Advances in understanding lung cancer biology and tumor markers aid clinicians in managing the disease. Cancer-associated antigen (CA)125 has garnered increasing attention in lung cancer research and may benefit the treatment and follow-up of this type of cancer. In Thai lung cancer patients, knowledge regarding ethnic differences in cancer cell biology is largely absent. We generated lung cancer cells from the pleural effusion fluids of a Thai patient and designated these as P1 cells. P1 cells were assessed for growth rate, response to chemotherapy, and the presence of tumor markers, in particular CA125 expression. Results of immunofluorescence indicated that P1 cells exhibited strong expression levels of CA125, comparable to that of established H460 lung cancer cells. Furthermore, P1 cells were analyzed for the expression of additional markers. Results revealed that H460 cells exhibited strong immunofluorescent signals from cytokeratin-19 fragments (CYFRA 21-1) and squamous cell carcinoma antigen (SCCA) while P1 presented only CYFRA 21-1 signals. We also found evidence of relative cisplatin resistance in P1 compared to the susceptibility level of established lung cancer cells. Thus, the results and methodology described in this study may aid the development of lung cancer diagnostic and therapeutic approaches and, in particular, advance understanding of ethnic differences.

Utility of serum tumor markers as an aid in the differential diagnosis of patients with clinical suspicion of cancer and in patients with cancer of unknown primary site

Cancer may be diagnosed in advanced stages, when the patient has already developed metastasis, with symptoms that can be also observed in benign diseases. The objective of this study was to evaluate tumor marker sensitivity and specificity in the differential diagnosis of patients with suspected signs of cancer. We studied 2.711 consecutive patients admitted to the Internal Medicine Department of our hospital with suspected cancer; 1.240 patients had non-malignant processes and 1.471 had malignant disease. Determinations were considered positive for suspected malignancy when serum levels were carcinoembryonic antigen >15 ng/ml (>20 in patients with renal failure or liver disease), alpha fetoprotein >40 ng/ml (>80 ng/ml in patients with liver diseases), carbohydrate antigen (CA) 19.9 > 200 U/ml (>500 U/ml in patients with liver diseases or gamma glutamyl transpeptidase (GGT) <150 UI/L or effusions; >1.000 U/ml in patients with jaundice or GGT > 150 UI/L), neuron-specific enolase >45 ng/ml (renal failure >50 ng/ml; samples with hemolysis were excluded), prostate-specific antigen > 30 ng/ml (excluding acute prostatitis), tumor-associated glycoprotein-72 >80 U/ml, cytokeratin 19 fragment 21-1 > 7.5 ng/ml (>19 ng/ml in patients with renal failure; >11 ng/ml in patients with liver cirrhosis or jaundice), >3.5 ng/ml for squamous cell carcinoma (excluding patients with renal failure or skin disorders), CA 15.3 >100 U/ml, and CA 125 >350 U/ml (>600 U/ml in patients with pleural effusion and >900 U/ml in those with ascites). There was a specificity of 97.6% in patients without malignancy, 67.4% of sensitivity in patients with malignancy, and 75.4% of sensitivity in the 1,280 patients with epithelial tumors (53.7% in patients with locally advanced tumors and 79.4% in patients with metastases). Sensitivity was 81.4% in patients with cancer of unknown primary site. Tumor markers were useful in the differential diagnosis between epithelial and non-epithelial tumors, brain masses (metastases vs. primary tumors), and between benign or malignant origin of different clinical situations such as wasting syndrome, effusions, liver or bone lesions, and effusions with a positive predictive value higher than 95%. Tumor markers are useful as an aid in the evaluation of the risk of cancer of these patients with suspected cancer and may be useful to reduce the hospitalization time, morbidity, and the number of diagnostic tests required for diagnosis.

Comparison of serum human epididymis protein 4 with cancer antigen 125 as a tumor marker in patients with malignant and nonmalignant diseases

BACKGROUND

Human epididymis protein 4 (HE4), a precursor of human epididymis protein, has been proposed as a tumor marker for ovarian cancer. We evaluated HE4 in comparison with cancer antigen 125 (CA 125) in healthy individuals and in patients with benign and malignant diseases.

METHODS

CA 125 and HE4 serum concentrations were determined in 101 healthy individuals, 535 patients with benign pathologies (292 with benign gynecologic diseases) and 423 patients with malignant diseases (127 with ovarian cancers). CA 125 and HE4 cutoffs were 35 kU/L and 140 pmol/L, respectively.

RESULTS

HE4 and CA 125 results were abnormal in 1.1% and 9.9% of healthy individuals and in 12.3% and 37% of patients with benign diseases, respectively. Renal failure was the most common cause of increased HE4 in patients with benign disease, who had significantly higher HE4 concentrations (P = 0.001) than patients with other benign diseases. HE4 showed a higher specificity than CA 125 in patients with benign gynecologic diseases, with abnormal concentrations in 1.3% and 33.2% of the patients, respectively. HE-4 concentrations were abnormal primarily in gynecologic cancer and lung cancer. By contrast, CA 125 was increased in many different nonovarian malignancies, including nonepithelial tumors. A significantly higher area under the ROC curve was obtained with HE4 than with CA 125 for differentiating benign from malignant diseases (0.755 vs 0.643) and in the differential diagnosis of gynecologic diseases (0.874 vs 0.722).

CONCLUSIONS

HE4 has significantly higher diagnostic specificity than CA 125, and the combination of CA 125 and HE4 improved the detection of ovarian cancer in all stages and histological types.

Increased plasma concentrations of tumour markers in the absence of neoplasia

Tumour markers are a very heterogeneous group of molecules that are generally found in very small concentrations in the plasma and serum of healthy individuals. In the process of neoplastic differentiation the cell can synthesize, release, or induce synthesis of other cells, thus increasing their concentration in plasma and serum. These substances may also increase their plasma concentration in patients without cancer due to processes that increase the release or reduce catabolism, and so give rise to false positives. An understanding of the main physiopathological processes that increase the concentrations of these substances could improve our interpretation of tumour markers and their clinical application. In this study we review the physiopathological processes that may increase the plasma concentrations of tumour markers. We performed a bibliography review in PubMed, searching for causes of false positives for the following tumour markers: α-Fetoprotein, CA 125, CA 15-3, CA 19-9, CA 72-4, carcinoembryonic antigen, CYFRA 21-1, squamous cell carcinoma, prostatic specific antigen, β(2)-microglobulin, choriogonadotropin (β chain), chromogranin A, neuron specific enolase, HER2-neu, progastrin releasing peptide, S-100, and thyroglobulin. The results favour the use of tests which can identify pathological processes that may increase tumour marker concentrations.

HE4 a novel tumour marker for ovarian cancer: comparison with CA 125 and ROMA algorithm in patients with gynaecological diseases

The aim of this study is to evaluate a new tumour marker, HE4, in comparison with CA 125 and the Risk of Ovarian Malignancy Algorithm (ROMA) in healthy women and in patients with benign and malignant gynaecological diseases. CA 125 and HE4 serum levels were determined in 66 healthy women, 285 patients with benign gynaecological diseases (68 endometriosis, 56 myomas, 137 ovarian cysts and 24 with other diseases), 33 patients with non-active gynaecological cancer and 143 with active gynaecological cancer (111 ovarian cancers). CA 125 and HE4 cut-offs were 35 U/mL and 150 pmol/L, respectively. ROMA algorithm cut-off was 13.1 and 27.7 for premenopausal or postmenopausal women, respectively. HE4, CA 125 and ROMA results were abnormal in 1.5%, 13.6% and 25.8% of healthy women and in 1.1%, 30.2% and 12.3% of patients with benign diseases, respectively. Among patients with cancer, HE4 (in contrast to CA 125) had significantly higher concentrations in ovarian cancer than in other malignancies (p < 0.001). Tumour marker sensitivity in ovarian cancer was 79.3% for HE4, 82.9% for CA 125 and 90.1% for ROMA. Both tumour markers, HE4 and CA 125 were related to tumour stage and histological type, with the lowest concentrations in mucinous tumours. A significantly higher area under the ROC curve was obtained with ROMA and HE4 than with CA 125 in the differential diagnosis of benign gynaecological diseases versus malignant ovarian cancer (0.952, 0.936 and 0.853, respectively). Data from our population indicate that ROMA algorithm might be further improved if it is used only in patients with normal HE4 and abnormal CA 125 serum levels (cancer risk for this profile is 44.4%). ROMA algorithm in HE4 positive had a similar sensitivity and only increases the specificity by 3.2% compared to HE4 alone.

Significance of DNA ploidy analysis and carcinoembryonic antigen assay for differential diagnosis between benign and malignant ascites

AIM: To investigate the differential diagnostic significance of DNA ploidy analysis and serum, ascetic carcinoembryonic antigen (CEA), ascites/serum CEA ratios assay in malignant (PHC and non-PHC malignancy) and benign ascites.

METHODS: Flow cytometry (FCM) was used for DNA ploidy analysis and enzyme linked immunosorbent assay (ELISA) for CEA assay in 56 malignant (31 PHC and 25 non-PHC) ascites. As a control, 50 nonmalignant ascites were evaluated at the same time. If the serum or ascitic CEA value >5 μg/L, and the ascites/serum CEA ratios >1, then the CEA assay was defined as positive. If an aneuploidy was detected, the result of the DNA ploidy analysis was defined as positive.

RESULTS: The sensitivity and specificity of ascitic CEA, ascites/serum CEA ratios>1 and aneuploidy in differential diagnosis of PHC ascites and non-PHC with malignant ascites or with benign ascites were 35.48%, 84% and 72%, 84%; 35.48%, 98% and 72%, 98%; 70.97%, 86% and 71.43%, 86%, respectively. The sensitivity and specificity of the combination assay of aneuploidy and ascites/serum CEA ratios >1 in differential diagnosis of PHC ascites and non-PHC with malignant ascites or with benign ascites were 93.55%, 100%; 92%, 100%, respectively.

CONCLUSION: Our study confirmed the differential diagnostic value between benign and malignant ascites of the combination assay of ascites/serum CEA ratios assay and the DNA ploidy analysis.

Correlation of Tumour Markers in Ascitic Fluid and Serum: Are Measurements of Ascitic Tumour Markers a Futile Attempt?

Correlations between tumour markers in ascitic fluid and serum were investigated to determine whether ascitic fluid analysis had any diagnostic advantage over serum in 91 adults with ascites (55 malign; 36 benign). Serum and ascitic fluid were analysed for carcinoembryonic antigen (CEA), cancer antigen (CA) 125, CA19.9, CA72.4, CA15.3, α-fetoprotein (AFP) and cytokeratin-19 fragment (CYFRA). The tumour markers were skewed between the groups so were logarithmically transformed. Correlations between serum and ascitic fluid were tested using Pearson's correlation coefficient. Serum and ascitic fluid levels of CEA, CA125, CYFRA and AFP in the malign group were statistically different and CEA, CA19.9, CA5.3, CYFRA and AFP were statistically different in the benign group. For both groups, all tumour markers were highly correlated in serum and ascitic fluid, with the exception of CYFRA in the malign group. These results indicate that, where malignant ascites is suspected, analysing tumour markers in ascitic fluid does not have any advantage over serum analysis.

(1)H NMR spectroscopy of ascitic fluid: discrimination between malignant and benign ascites and comparison of the results with conventional methods

It is often difficult to distinguish benign ascites from malignant ascites by conventional examination of ascitic fluid. Therefore, (1)H NMR spectroscopy of ascitic fluid specimens was explored as a one-shot experiment to identify potentially interesting metabolic indices that might help to differentiate between the two. Seventy ascitic fluid specimens (15 cytologically positive for malignant cells, eight cytologically negative for malignant cells but remaining suspicious for malignant ascites, and 47 due to liver cirrhosis) were subjected to (1)H NMR spectroscopy for quantitative estimation of 14 metabolites. Mean concentrations of the metabolites were compared with the Mann-Whitney U test. Multivariate discriminant function analysis was performed to determine important descriptors in the discrimination process. The sensitivity and specificity of the proposed model were compared with conventional methods using ascitic fluid protein and serum ascitic albumin gradient. Then, probable predictions for the doubtful cases were made using the proposed model. Patients with malignant ascites had significantly higher mean concentrations (microM) of beta-hydroxybutyrate (594 vs 61), lactate (5384 vs 2104), acetone (136 vs 69), and acetoacetate (122 vs 48) than patients with cirrhotic ascites, and significantly lower concentrations of glutamine (359 vs 615), citrate (62 vs 118), glucose (4933 vs 8411), tyrosine (44 vs 124), and phenylalanine (51 vs 93) (P < 0.05 for all). In the discriminant function analysis model, the best discrimination (P < 0.001) was achieved when beta-hydroxybutyrate, lactate, citrate and tyrosine were considered together as markers. Sensitivity and specificity of the proposed model, ascitic fluid protein and serum ascitic albumin gradient were found to be 100% and 97.9%, 53.3% and 76.6%, and 60% and 87.2%, respectively. The proposed model put five of the eight doubtful cases in the malignant group. This is encouraging and may provide useful information for clinical purposes.

Vascular endothelial growth factor levels in ascites between chemonaive and chemotreated patients

PURPOSE

Vascular endothelial growth factor (VEGF) levels in malignant ascites have high diagnostic value for their discrimination from ascites of non-malignant origin. However, there have been no reports on the comparison of VEGF levels between malignant ascites of chemonaive and chemotreated patients.

MATERIALS AND METHODS

VEGF levels were measured in 44 ascites patients (cirrhosis ascites, 10; chemonaive patients, 21; chemotreated patients, 13) and compared to the level of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA 19-9). The diagnostic parameters of sensitivity, specificity, and correlation among 3 markers were evaluated.

RESULTS

VEGF levels in malignant ascites of chemonaive and chemotreated patients were significantly higher than those in cirrhotic ascites (p<0.05). VEGF levels in ascites of chemonaive patients were significantly higher than those in chemotreated patients (p<0.05). A cutoff value of 10.4 pg/mL was calculated using receiver operating characteristic curves (ROCs) for VEGF in chemotreated and chemonaive patients, which gave sensitivities of 75.0% and 53.8% and specificities of 69.6% and 47.1%, respectively. Positive correlations were observed between VEGF and CEA (r=0.353, p<0.05) as well as between VEGF and CA19-9 (r=0.367, p<0.05) in ascites.

CONCLUSION

VEGF levels could be a useful tumor marker for malignant ascites, but its value should carefully be interpreted because of lesser reliability in chemotreated ones.

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.

Evaluation of serum and pleural levels of the tumor markers CEA, CYFRA21-1 and CA 15-3 in patients with pleural effusion

OBJECTIVE

To determine the levels of the tumor markers carcinoembryonic antigen (CEA), cytokeratin 19 fragment (CYFRA21-1) and carbohydrate antigen 15-3 (CA 15-3) in the blood and pleural fluid of patients with benign or malignant pleural effusion, evaluating the sensitivity of each marker in these fluids.

METHODS

We prospectively evaluated 85 patients with pleural effusion. The study of the pleural fluid observed the criteria established in the literature. Levels of the markers were determined using electrochemiluminescence. The sensitivity was determined on the condition that the specificity was > or = 90%.

RESULTS

Of the 85 cases, 36 (42.4%) were malignant, 30 (35.3%) were benign, and the results were inconclusive in 19 (22.3%). In the malignant cases, the CEA and CYFRA21-1 levels were higher in the pleural fluid than in the blood, which was not observed for CA 15-3. In the benign cases, the CYFRA21-1 levels were higher in the pleural fluid than in the blood, whereas the opposite was found for CEA and CA 15-3. There were significant differences between malignant and benign cases for all markers, in pleural fluid and blood. In the pleural fluid, the sensitivity of CEA, CYFRA21-1 and CA 15-3 was 69.4, 69.4 and 66.7%, respectively, and the combined sensitivity was 80.6%. In the blood, the sensitivity was 57.1%, 71.4% and 48.6% for CEA, CYFRA21-1 and CA 15-3, respectively, and the combined sensitivity was 77%.

CONCLUSION

The results suggest that these markers might be useful in the differentiation between malignant and benign pleural effusion.

Body fluid proteomics: Prospects for biomarker discovery

Many diseases are caused by perturbations of cellular signaling pathways and related pathway networks as a result of genetic aberrations. These perturbations are manifested by altered cellular protein profiles in the fluids bathing tissue/organs (i.e., the tissue interstitial fluid, TIF). A major challenge of clinical chemistry is to quantitatively map these perturbed protein profiles - the so-called "signatures of disease" - using modern proteomic technologies. This information can be utilized to design protein biomarkers for the early detection of disease, monitoring disease progression and efficacy of drug action. Here, we discuss the use of body fluids in the context of prospective biomarker discovery, and the marked 1000-1500-fold dilution of body fluid proteins, during their passage from TIF to the circulatory system. Further, we discuss proteomics strategies aimed at depleting major serum proteins, especially albumin, in order to focus on low-abundance protein/peptides in plasma. A major limitation of depletion strategies is the removal of low-molecular weight protein/peptides which specifically bind major plasma proteins. We present a prototype model, using albumin, for understanding the multifaceted nature of biomarker research, highlighting the involvement of albumin in Alzheimer's disease. This model underscores the need for a system-level understanding for biomarker research and personalized medicine.

Values of simultaneous determination of 5 tumor markers in fluid and serum and their ratio in differential diagnosis of benign and malignant ascites

AIM: To evaluate the values of the simultaneous determination of tumor markers AFP, CEA, CA19-9, CA50 and CA125 in fluid and serum, and their ratio (F/S) in the differential diagnosis of benign and malignant ascites.

METHODS: Serum and ascites fluid specimens were simultaneously collected from 105 patients with ascites (benign 57, malignant 48). The tumor markers AFP, CEA were determined by electrochemoluminescence. The tumor markers CA19-9, CA50 and CA125 were measured with radioimmunoassay (RIA).

RESULTS: The F/S ratios were all lower than 1.2 in benign ascites fluid and higher than 1.2 in the majority of malignant fluid when the tumor marker content in fluid was higher than the normal cut-off of serum (AFP > 25 μg/L, CEA > 5 μg/L, CA19-9 > 37 kU/L and CA50 > 20 mg/L). The combination of a F/S ratio greater than 1.2 and a cut-off stated above showed sensitivities of 18.8%, 62.5%, 58.3% and 72.9%, respectively for AFP, CEA, CA19-9 and CA50, with a specificity of 100%, These sensitivities were significantly higher than those of a single determination of concentration in fluid or F/S ratio (16.7%, 37.5%, 29.2% and 47.9%)(P < 0.01) besides AFP. The combined sensitivity of 4 tumor markers and their F/S ratios was 91.7% with a specificity of 100%.

CONCLUSION: In comparison with either single determination of concentration in serum or fluid, the sensitivity and specificity of tumor markers AFP, CEA, CA19-9 and CA50 can be significantly increased by simultaneous determination of the concentration in fluid and their F/S ratio.

Values of multifunctional peritoneal biopsy needle in diagnosis of benign and malignant ascites

AIM: To evaluate the values of the multifunctional peritoneal biopsy needle in the differential diagnosis of benign and malignant ascites.

METHODS: Routine cytological examination, biopsy and brush cytology were performed in 327 patients with ascites using multifunctional peritoneal biopsy needle, and then the cytological results were analyzed.

RESULTS: All the benign ascites were diagnosed as benign using the multifunctional peritoneal biopsy needle, and the specificity was 100%. For the malignant ascites, the diagnostic sensitivity of the routine ascitic cytology was 53.4%(101/189), and those of biopsy and brush cytology were 90.5%(171/189) and 83.1%(157/189) respectively. After biopsy and brush cytology, the sensitivity of cytological examination was 90.0%(170/189). However, when the multifunctional peritoneal biopsy needle was used, the sensitivity of co-examination was 93.7%(177/189), and the sensitivities of biopsy, brush cytology and the cytological examination after biopsy and brush cytology were significantly higher than that of routine ascitic cytology (χ² = 64.241, 38.288, 62.064, all P<0.001). The sensitivity of biopsy was markedly higher than that of brush cytology (χ² = 4.518,P<0.05), and the sensitivity of ascitic cytological examination after biopsy and brush cytology was higher than that of single brush cytology (χ² = 3.831, P<0.05). There was no significant difference between the sensitivities of biopsy and cytological examination as well as between the multifunctional peritoneal biopsy needle and cytological examination after single biopsy or single brush cytology. The sensitivity and accuracy of the multifunctional peritoneal biopsy needle were 93.7% and 96.3%, respectively, in diagnosis of benign and malignant ascites.

CONCLUSION: The multifunctional peritoneal biopsy needle is valuable in the differential diagnosis of benign and malignant ascites.