Pleural fluid biomarkers for the diagnosis and management of malignant pleural effusions: a clinical review

Use of a Panel of Tumor Markers (Carcinoembryonic Antigen, Cancer Antigen 125, Carbohydrate Antigen 15–3, and Cytokeratin 19 Fragments) in Pleural Fluid for the Differential Diagnosis of Benign and Malignant Effusions

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. 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). 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. 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.

BackgroundPleural 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.MethodsPatients 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).ResultsPopulation 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.ConclusionsPleural 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.

The presence of tumour cells in pleural fluid or tissue defines an effusion as malignant. Cytology analysis of the pleural fluid has about 60% diagnostic sensitivity. Several tests have been proposed to improve diagnosis-among them, the concentrations of tumour markers in pleural fluid. We evaluated whether the concentrations of tumour markers in pleural fluid could improve the diagnosis of malignant pleural effusion (mpe) when cytology is doubtful. Lymphocytic pleural fluids secondary to tuberculosis or malignancy from 156 outpatients were submitted for cytology and tumour marker quantification [carcinoembryonic antigen (cea), cancer antigen 15-3 (ca15-3), carbohydrate antigen 19-9 (ca19-9), cancer antigen 72-4 (ca72-4), cancer antigen 125 (ca125), and cyfra 21-1). Oneway analysis of variance, the Student t-test or Mann-Whitney test, and receiver operating characteristic curves were used in the statistical analysis. Concentrations of the tumour markers cea, ca15-3, ca125, and cyfra 21-1 were higher in mpes than they were in the benign effusions (p < 0.001), regardless of cytology results. The markers ca19-9 and ca72-4 did not discriminate malignant from benign effusions. When comparing the concentrations of tumour markers in mpes having positive, suspicious, or negative cytology with concentrations in benign effusions, we observed higher levels of cea, ca15-3, cyfra 21-1, and ca125 in malignant effusions with positive cytology (p = 0.003, p = 0.001, p = 0.002, and p = 0.001 respectively). In pleural fluid, only ca125 was higher in mpes with suspicious or negative cytology (p = 0.001) than in benign effusions. Given high specificity and a sensitivity of about 60%, the concentrations of tumour markers in pleural effusions could be evaluated in cases of inconclusive cytology in patients with a high pre-test chance of malignancy or a history of cancer.

Study objectiveTo evaluate the diagnostic value of four different tumor markers: cancer antigen 125 (CA-125), carcinoembryonic antigen (CEA), cytokeratin 19 fragment (CYFRA 21-1) and neuron specific enolase (NSE) in patients with malignant and non-malignant pleural effusion.Material and methodsOne hundred and two patients with pleural effusion treated in the University Hospital in Warsaw between 2001 and 2003 were studied. They underwent an extensive, diagnostic work-up in order to determine the pleural effusion etiology. Patients with known pleural fluid etiology were labeled as the study group and submitted for further analysis. Pleural fluid and serum samples for CA-125, CEA, CYFRA 21-1 and NSE measurements were collected during the first thoracentesis, centrifuged, and frozen until further use. Pleural fluid and serum concentration of tumor markers were assessed by electrochemiluminescence methods using commercial kits.Results74 patients (32 M, 42 F; mean age 65 ± 14 years) composed the final study group. Exudative pleural effusion was found in 62 patients; of these 36 were malignant (48.6% of all effusions), 20 parapneumonic (or pleural empyema), and 6 tuberculous. In 12 patients, pleural transudate was diagnosed. The highest diagnostic sensitivity for malignant pleural effusion was found for NSE (94.4% and 80.6% in the pleural fluid and serum, respectively). However, the specificity of NSE measurement was relatively low (36.1% and 47.4% in pleural fluid and serum, respectively). The most specific markers of malignant pleural fluid etiology were pleural fluid CYFRA 21-1 and CEA levels (92.1% and 92.1%, respectively). CA-125 was found to be the most specific serum marker of pleural malignancies (78.9%). The AUC for combined pleural markers was 0.89, combined serum markers 0.82, combined ratio pleural/serum markers 0.88.ConclusionsThere are significant differences between the diagnostic value of various pleural fluid and serum markers. Overall, pleural fluid markers are superior to serum markers in determining the pleural fluid etiology. A combination of two or more tumor markers may help improve their diagnostic accuracy. Pleural fluid and serum measurements of different tumor markers play a limited role in the differentiation between malignant and non-malignant pleural effusions.

The aim of this study was to evaluate the individual and combined diagnostic value of five tumour markers in the elderly patients with pleural effusions. Serum and pleural fluid levels of cytokeratin fragment 19 (CYFRA21-1), neuron-specific enolase (NSE), carbohydrate antigen 15-3 (CA15-3), carbohydrate antigen 19-9 (CA19-9) and carbohydrate antigen 125 (CA125) were assayed in 32 elderly patients with malignant pleural effusions resulting from advanced lung cancer and in 30 elderly patients with benign pleural effusions by ELISA. Serum levels of CYFRA21-1, NSE, CA15-3, CA19-9 and CA125 in patients with malignant pleural effusions were 12.84 +/- 6.48 microg/l, 22.07 +/- 11.25 microg/l, 65.74 +/- 30.26 kU/l, 56.32 +/- 25.6 kU/l and 71.86 +/- 31.45 kU/l, respectively, and were significantly higher than those in patients with benign pleural effusions (p < 0.01). Pleural fluid levels of CYFRA21-1, CA15-3, CA19-9 and CA125 except NSE in patients with malignant pleural effusions were 18.64 +/- 8.15 microg/l, 59.31 +/- 27.35 kU/l, 48.24 +/- 21.56 kU/l and 62.16 +/- 27.79 kU/l, respectively, and were significantly higher than those in patients with benign pleural effusions (p < 0.01). The parallel combined testing of five tumour markers in serum increased the diagnostic sensitivity to 90.6%, and serial combined testing increased the diagnostic specificity to 93.3%. The sensitivity (%) and specificity (%) of these tumour markers in pleural fluid were as follows: CYFRA21-1, 84.4/90; CA15-3, 62.5/73.3; CA19-9, 37.5/66.7; CA125, 56.3/70; for differentiating malignant effusions from benign effusions. When CYFRA21-1 and CA15-3 combined, the sensitivity and specificity were increased (100% and 90% respectively). Serum and pleural fluid levels of the five tumour markers shows certain values in the diagnosis and differentiate diagnosis for malignant pleural effusions in the elderly patients from benign. The combined assay of five tumour markers in serum and the CYFRA21-1 combined with CA15-3 in pleural fluid were helpful and can increase the sensitivity and specificity in diagnosing malignant pleural effusions.

The significance of carbohydrate (cancer) antigen 125 (Ca-125) and carcinoembryonic antigen (CEA) tumour markers levels in differential diagnostics of malignant and benign pleural effusion was studied. Within this prospective study, 121 patients with fluids of various aetiology in the pleural cavity were analysed. Malignant pleural effusion was detected in 55 patients, parapneumonic effusion in 28 patients, transudative effusion of cardiac origin in 31 patients, pancreatitis in one patient and tuberculous pleurisy in five patients. The highest accuracy in diagnosis of malignancy was observed for Ca-125 and CEA levels in the pleural fluid: 75.2% at cut-off value ≥1452 U/mL and 76.9% at cut-off value ≥6.58 ng/mL, respectively. We conclude that the level of tumour markers in pleural fluid has additional diagnostic significance in the differential diagnosis of malignant and benign pleural effusions.

The Association Between Pleural Fluid Exposure and Survival in Pleural Mesothelioma

Serum and pleural fluid tumor markers are well-recognized auxiliary diagnostic tools for malignant pleural effusion (MPE). Here, we discuss some pearls andpitfalls regarding the role of tumor markers in MPE management. The following issues are discussed in this article: What is the appropriate clinical scenario for evaluating pleural tumor markers? Which tumor markers should be advocated for diagnosing MPE? Can extremely high levels of tumor markers be employed to establish a diagnosis of MPE? Does the serum-to-pleural fluid ratio of a tumor marker have the same diagnostic efficacy as the measurement of that marker alone in the pleural fluid? Can tumor markers be usedto estimate the risk of specific cancers? What should beconsidered when interpreting the diagnostic accuracy of tumor markers? How should tumor marker studies be performed? We addressed these issues with published works, particularly systematic reviews and meta-analyses.

Objective To investigate the significance of combined detection of tumor markers in serum and pleural fluid on differential diagnosis of benign and malignant pleural effusion.Methods Three hundred and seventy six cases of pleural effusion were selected.The levels of carcinoembryonic antigen (CEA),neuronspecific enolase(NSE),cancer antigen 125 ( CA125 ),squamous cell carcinoma antigen (SCC) in serum and pleural fluid were examined and they were analyzed combined with histological or cytological evidence using statistical methods.Results There were 298 cases in malignant group and 98 cases in benign group.The levels of the four tumor markers in malignant group were significantly higher than in benign group both in pleural fluid (CEA:[279.9 ± 170.0]μg/L v.s.[ 12.6 ± 6.2 ] μg/L,t =6.29,P ＜ 0.01; NSE:[ 112.3 ± 86.8 ] μg/L v.s.[14.7 ±7.3] μg/L,t =5.13,P ＜0.01 ;SCC:[ 10.6 ± 5.4] μg/L v.s.[ 1.2 ±0.6 ] μg/L,t =2.34,P ＜0.01;CA125:[ 409.2 ± 206.7] U/ml v.s.[ 44.0 ± 20.5 ] U/ml,t =7.46,P ＜ 0.01 ) and in serum ( CEA:[ 86.7 ±42.0] μg/L v.s.[6.2±3.1]μg/L,t=3.14,P＜0.01;NSE:[31.6±18.2]μg/Lv.s.[11.2±5.0]μg/L,t=4.61,P＜0.01;SCC:[3.5±2.2]μg/Lv.s.[1.8±0.g]μg/L,t=1.70,P＜0.01;CA125:[134.0±72.6]U/ml v.s.[ 19.8 ± 9.6 ] U/m1,t =4.04,P ＜ 0.01 ).Moreover,the levels of tumor markers in pleural fluid were higher than in serum.The sensitivity were 100％ by combined detection of pleural fluid and serum tumor markers in parallel and the specificity were 100％ in sequence.Conclusion The levels of CEA,NSE,CA125,SCC in pleural effusion were more sensjtive than which in serum.Combined detection of tumor markers in pleural fluid and serum could improve the sensitivity of diagnosis for benign and malignant pleural effusion. Key words: Pleural fluid; Tumor markers; Carcinoemhryonic antigen; Neuron-specific enolase; Cancer antigen 125 ; Squamous cell carcinoma antigen

The Optimal Treatment of Malignant Pleural Effusions A Continuing Dilemma

Background/Objectives: Malignant pleural effusions (MPEs) pose a significant challenge in clinical practice and exert a considerable socio-economic burden on the healthcare system, affecting approximately 1 million individuals annually. These effusions are a leading cause of debilitating dyspnea and a diminished quality of life among cancer patients, with distant metastasis to the pleural layers occurring in about 20% of cases during treatment. Methods: A cross-sectional, observational case-control study was conducted on 151 Bulgarian patients with a hydrothorax. The control group included 72 patients with benign diseases, confirmed via biopsy, with 38 having inflammatory and 34 non-inflammatory pleural effusions. The other 79 patients had malignant pleural involvement. These groups are representative of the main types of pleural pathology. Results: The study found that all of the tumor markers, except for PIVKA-II (Protein induced by vitamin K absence-II), showed statistically significant differences between the malignant and non-malignant patient groups, with CAE (carcinoembryonic antigen) and CA19-9 showing the most notable differences. The Receiver Operating Characteristic (ROC) analysis revealed that CA72-4 had the best ability to distinguish between the two groups, while PIVKA was the weakest, with optimal cut-off values for all of the relevant tumor markers being derived using the Youden index. Conclusions: In conclusion, our study highlights the transformative potential of pleural fluid tumor markers as precise and minimally invasive resources for distinguishing malignant from non-malignant pleural effusions. These findings pave the way for improved diagnostic accuracy and personalized clinical management, addressing a critical gap in the care of patients with pleural pathologies.

Rebuttal From Dr Lee

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.

BACKGROUND: Malignant and paramalignant pleural effusions are important complications of many malignancies. The two main management options debated in the literature are: 1) insertion of an indwelling pleural catheter (IPC) to achieve chronic drainage of the effusion, or 2) hospitalization with tube thoracostomy and subsequent chemical pleurodesis (CP) with talc or doxycycline to prevent fluid reaccumulation. We aimed to describe a large series of patients with malignant pleural effusions managed with an IPC, identify and validate factors identified in the literature as predictors of spontaneous pleurodesis in the IPC group and compare the group managed with IPC to patients managed with CP. METHODS: We designed a retrospective cohort study comparing patients with malignant and paramalignant pleural effusions managed either with CP between March 1, 2003 and February 28, 2006 or IPC insertion between May 1, 2006 and April 1, 2009. The CP group was identified through the prescription of talc or doxycycline and the IPC group from the IPC clinic database. Data were collected from paper and electronic records and from the Government of Ontario. RESULTS: We identified 193 consecutive patients with an ECOG performance status of less than 4 (ECOG less than 4 means that the patient is not completely disabled and confined to bed or chair) having undergone IPC insertion and 168 who were managed with CP. None of the variables we tested were significant predictors of spontaneous pleurodesis in the IPC group. Pleural effusion control rates at 6 months were higher in the IPC group than in the CP