The clinical value of neuron-specific enolase as a tumor marker in bronchoalveolar lavage

The Concentrations of Five Tumor Markers in Both Bal Fractions in Lung Cancer Patients in Relation to Cigarette Smoking

Background

Lung cancer is the leading cause of death from cancer. Tobacco is related to the development of this type of tumor due to genetic alterations and to the secretion of certain biological markers. Bronchogenic carcinomas secrete a series of biological substances known as tumor markers. Some of these markers, such as carcinoembryonic antigen, neuron-specific enolase, tissue polypeptide antigen (TPA), tissue polypeptide-specific antigen (TPS) and CYFRA 21.1, possess clear clinical value when analyzed in bronchoalveolar lavage (BAL) of patients with lung malignancies, particularly when they are analyzed in the two BAL fractions, bronchial (BF) and alveolar (AF), being more increased in the BF. For this reason, we intend to demonstrate that smokers with cancer secrete more biological substances in the BF and that the concentrations of these markers are higher in the BAL of smokers than in that of non-smokers.

Methods

The five aforementioned tumor markers were studied in the two BAL fractions of 52 lung cancer patients (46 smokers and 6 non-smokers). We performed BAL using 150 ml of 0.9% saline solution divided in three aliquots of 50 ml. The fluid obtained from the first 50 ml was the BF. The liquid from the other two aliquots was the AF. The five tumor marker concentrations were calculated in accord with the indications of the laboratory.

Results

The TPA and TPS levels in the BAL of lung cancer patients were more increased in the BF than in the AF, even when the patients were divided into smokers and non-smokers. When we compared smokers with non-smokers, the smokers had higher levels of TPS in the BF and of TPA in the AF.

Conclusions

Thus, we believe that the cellular alterations produced by tobacco are responsible for the secretion of these tumor markers.

Purification of a Tumoral Marker Recognized by Monoclonal Antibody Po66 and Associated with Human Lung Squamous Cell Carcinoma

Monoclonal antibody (MAb) Po66, a murine IgG1, was raised by immunization against human lung squamous cell carcinoma. When injected intravenously, Po66 showed prolonged retention in the tumor. It recognized an intracellular antigen. The human lung squamous carcinoma cell line SK-MES-1 expresses the antigen recognized by MAb Po66 and was used as a source of biological material for its purification. The SK-MES-1 cell line was labeled in culture with [35S]methionine and its lysate was immunoprecipitated with Po66 immobilized on Protein G-Sepharose. The precipitate contained three proteins (47, 50 and 69 kDa) absent in the controls. The 69 kDa polypeptide was further purified by anion exchange and immunoaffinity chromatographies. To date, no other tumor marker expressed in non-small cell lung cancer with these characteristics has been described and as such this marker is interesting for future use in immunotherapy and in diagnosis.

Evaluation of diagnostic value of four tumor markers in bronchoalveolar lavage fluid of peripheral lung cancer

AIM

The diagnostic role of carcinoembryonic antigen (CEA), squamous cell carcinoma (SCC) antigen, Cyfra 21-1 and neuron-specific enolase (NSE) in the bronchoalveolar lavage fluid (BALF) for lung cancer is still controversial. The aim of this study was to evaluate the diagnostic value of these four tumor markers in BALF for peripheral lung cancer.

METHODS

We measured and compared the levels of CEA, SCC, Cyfra21-1 and NSE in BALF in 42 patients with peripheral lung cancer and 22 patients with benign lung disease. In the patients with peripheral lung cancer, the BAL was separately performed in the bronchus of the tumor-bearing lung and in the corresponding bronchus of the opposite healthy lung.

RESULTS

The levels of CEA, SCC, Cyfra21-1 and NSE were significantly elevated in BALF from the tumor-bearing lung compared with the opposite healthy lung in the lung cancer patients (P < 0.001) or the benign lung disease patients (P < 0.005). The diagnostic sensitivities of Cyfra21-1 (86 and 76%), with a specificity of 91%, were the highest among the four tumor markers for the tumor-bearing lung versus the opposite healthy lung and benign lung disease. The combination of Cyfra21-1 and CEA increased the sensitivity to 93 and 86 percent, respectively.

CONCLUSION

The assay of these tumor markers in BALF may be used as a diagnostic tool to complement a cytological examination in the diagnosis of peripheral lung cancer.

Neuron-specific enolase and lung cancer

OBJECTIVE

Serum and bronchoalveolar lavage fluid (BALF) neuron-specific enolase (NSE) levels in lung cancer have been investigated widely; however, their diagnostic values have not yet been clarified. The authors investigated the diagnostic validity of NSE in BALF and serum in lung cancer.

MATERIALS AND METHODS

In this prospective case-control study, NSE levels in BALF (B-NSE) and serum (S-NSE) of 3 groups of subjects were analyzed: control subjects (group 1, n = 15), patients with chronic obstructive pulmonary disease (COPD; group 2, n = 15), and lung cancer (group 3, n = 35).

RESULTS

The differences in S-NSE and B-NSE levels between the groups were not significant (P > 0.05). S-NSE and B-NSE levels did not show any difference between smokers and nonsmokers, small cell lung cancer and nonsmall cell lung cancer patients, and stage I-II and stage III-IV patients in group 3 (P > 0.05). B-NSE or B-NSE/urea did not show any significance in comparison with S-NSE in the diagnosis and/or staging of malignancy (P > 0.05). S-NSE and B-NSE were well correlated with each other (r = 0.84, P = 0.000). The sensitivity of the S-NSE was 60% and the specificity was 40%.

CONCLUSION

The authors conclude that, although elevation of B-NSE is a well-known parameter in small cell lung cancer, it can also be elevated considerably in nonsmall cell lung cancer and COPD. Because of the significant correlation between S-NSE and B-NSE, it may be sufficient to measure S-NSE activity because it is easier and less invasive. However, NSE has no role in the exact diagnosis of lung cancer; it can only be investigated in a scientific setting.

Increased Levels of Albumin in Bronchial Washing Fluid of Patients with Bronchial Carcinoma. Could Albumin be Considered as a Tumor Marker?

Background

The aim of this study was to evaluate the significance of albumin in bronchial washing fluid (BWF) and its relationship to three tumor markers (CEA, CA 19–9 and NSE).

Methods

Serum and BWF samples were collected in a group of 60 patients. Albumin and tumor markers in the BWF and serum of three groups: a control group (CG), a chronic bronchitis group (CBG) and a lung cancer group (CaG), were analyzed in a prospective cross-sectional study. The diagnostic yields of the tests in each environment (serum and BWF) were evaluated by using as cutoff points the values of the corresponding 90th percentile of CG and CBG taken together.

Results

A significant difference in albumin level (p<0.001) was noted in the BWF of patients with cancer compared with the other two groups. In addition, a significant difference in CEA level (p<0.001) was observed in the serum of cancer patients compared with the other two groups. The cutoff values for CEA in serum and albumin in BWF were 2.20 ng/mL and 2.00 g/dL, respectively. The areas under the corresponding ROC curves were 93% and 97%. Combination of CEA-serum and albumin-BWF by logistic regression analysis increased their diagnostic value.

Conclusion

Measurement of albumin levels in BWF could be a useful additional diagnostic tool to differentiate malignant from non-malignant lung diseases. Moreover, the combined measurement of CEA in serum and albumin in BWF could be of aid in the follow-up of lung cancer patients.

How to Express Tumor Markers in Bronchoalveolar Lavage

Introduction

Bronchoalveolar lavage (BAL) is a fundamental technique in the diagnosis of different respiratory diseases including lung cancer. Tumor marker values can be determined in the BAL fluid, but controversy still exists about how to express the results.

Objective

The aim of this study was to determine the best method of expressing tumor markers in BAL, either referring to total proteins or volume of fluid recovered.

Patients and Methods

A prospective, randomized, non-blind study was carried out. Seventy-six patients (72 men and 4 women) diagnosed with lung cancer and 17 subjects without respiratory disease were included. BAL was performed in all patients and the fluid retrieved was divided into two fractions: a bronchiolar fraction (F0) and an alveolar fraction (F1). Five tumor markers: cytokeratin fragment 19 (CYFRA 21–1), squamous cell carcinoma antigen (SCC), tissue polypeptide antigen (TPA), tissue polypeptide-specific antigen (TPS) and neuron-specific enolase (NSE) as well as total protein were measured in both fractions. The concentrations were expressed in relation to the volume of BAL fluid recovered (ng or mU/mL) and in milligrams of total protein of lavage fluid (ng or mU/mg TP). The SPSS 11.01 software was used for statistical analysis. Mann-Whitney U test and ROC curves were developed when significant differences were found.

Results

We found significant differences in the CYFRA 21-1 values in the two BAL fractions and in both ways of expressing its concentration; in SCC in F1 expressed in ng/mg TP; in TPA in F0 expressed in mU/mg TP; in TPS in both fractions expressed in mU/mg TP, and in NSE in both fractions in ng/mg TP. The markers that best differentiated tumors from controls (ROC curves) were CYFRA 21-1 in F0 and NSE in both fractions in ng/mg TP.

Conclusions

Our study demonstrates that the concentrations of tumor markers in BAL expressed in relation to total protein were more effective than if expressed in mL of BAL fluid collected.

Comparison of serum and bronchoalveolar lavage fluid sialic acid levels between malignant and benign lung diseases

BACKGROUND

It is known that tissue and serum sialic acid levels may be altered by malignant transformation. In this study, sialic acid levels were determined in bronchoalveolar lavage fluid (BAL) and serum in two groups of patients with lung cancer and non-malignant diseases of the lung.

METHODS

Colorimetric methods were used for determination sialic acid in serum and in BAL samples. Flexible bronchoscopy was used to obtain the latter.

RESULTS

Sialic acid levels in bronchoalveolar lavage fluid and serum did not show any statistically significant difference between subjects with malignant and the non-malignant lung diseases (p > 0.05). Sialic acid levels were also unrelated to the stage and localization of the tumor (p > 0.05).

CONCLUSIONS

Sialic acid levels do not appear to be a good marker for discriminating malignant from non-malignant diseases of the lung.

Tumour markers in serum, bronchoalveolar lavage and biopsy cytosol in lung carcinoma: what environment lends the optimum diagnostic yield?

BACKGROUND

The aim of this study was to assess the diagnostic yield of the tumour markers carbohydrate antigen (CA 125), carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), squamous cell carcinoma antigen (SCC) and specific tissue polypeptide antigen (TPS) in serum, bronchoalveolar lavage (BAL) and biopsy cytosol in a group of patients with bronchogenic carcinoma.

METHODS

Serum, BAL and biopsy cytosol samples were collected in a group of 85 patients with benign or malignant pulmonary diseases. After appropriate processing, tumour markers were determined by enzyme immunoassay. The diagnostic yields (sensitivity, specificity and accuracy) in each environment (serum, BAL or biopsy) were obtained by using "ROC" curves.

RESULTS

Determined individually, CA 125, NSE and SCC show the greatest diagnostic accuracy in cytosol. CEA and TPS do so in BAL. CEA is the most relevant marker in serum and BAL, and CA 125 in cytosol. When the different tumour markers are associated, they offer better overall yields for all except TPS.

CONCLUSIONS

For the factors evaluated in this study, determination of CEA in BAL was clinically the most useful marker in comparison with serum and cytosol determinations, although the latter may also be helpful in certain situations. Although there is no specific tumour marker for lung cancer, the combination of several can be used to monitor most patients with lung cancer.

Role of bronchoscopy in lung cancer research

The use of bronchoscopy for research into lung cancer is mostly limited by the imagination of the investigator. This technique allows the scientist direct access to tissue in a minimally invasive manner. We have discussed some of the applications of this technique in better understanding lung cancer. As we move onward in the areas of diagnosis and treatment of lung cancer, the bronchoscope will remain an important research tool.

High neuron specific enolase levels in bronchoalveolar lavage fluid of patients with lung carcinoma: diagnostic value, relation to serum neuron specific enolase, and staging

BACKGROUND

High levels of neuron specific enolase (NSE) have recently been described in the bronchoalveolar lavage (BAL) fluid of patients with lung carcinoma. Although its value in serum has been extensively studied, its diagnostic value in BAL fluid in terms of sensitivity, specificity, and predictive value have not been evaluated. In addition, its value in staging and relation to serum NSE are yet unknown.

METHODS

NSE levels were determined on the same day in the BAL fluid and the sera of two groups of patients: those with newly diagnosed lung carcinoma and those with smoking related chronic obstructive pulmonary disease (COPD). Clinical TNM staging was also performed. Levels of NSE in BAL fluid were expressed as nanograms per 100 international units of lactate dehydrogenase. BAL fluid NSE levels of the two groups were compared with staging and serum NSE.

RESULTS

A highly significant difference exists in BAL NSE in the two groups. For diagnostic purposes, the simultaneous measurements of serum NSE increases its sensitivity, but specificity remains unchanged. No correlation exists between BAL NSE and serum NSE, tumor size, nodal status, or the presence of metastases. BAL NSE is a better predictor of malignancy than serum NSE.

CONCLUSION

BAL fluid measurements of NSE may have diagnostic value, specially if it is simultaneously measured in the serum. However, our study does not show any value for this technique in staging of lung carcinoma. Also it has no correlation with serum NSE. Studies will have to be performed to determine if BAL NSE can predict chemotherapeutic sensitivity.

Cytokeratin tumor marker levels in bronchial washing in the diagnosis of lung cancer

STUDY OBJECTIVE

The monitoring of serum concentrations of Cyfra 21-1, tumor polypeptide antigen (TPA), and tissue polypeptide specific antigen (TPS) has been demonstrated to be useful in the clinical treatment of patients with lung cancer. This study was planned to evaluate the clinical usefulness of the assay of these tumor markers on bronchial washing (BW) fluid and to compare it with serum assay in patients with neoplastic and nonneoplastic disease.

STUDY DESIGN

Serum and BW fluid levels of Cyfra 21-1, TPA, and TPS were measured in 40 subjects (10 control subjects, 11 with chronic bronchitis, 10 with squamous cell lung cancer, and 9 with nonsquamous cell lung cancer) undergoing diagnostic bronchoscopy. BW was performed using 25 mL of pyrogen-free saline solution instilled through the working channel of the bronchoscope, and successively aspirated. The quantity of the fluid recovered was measured and used for the assay of albumin, Cyfra 21-1, TPA, and TPS.

RESULTS

Mean BW concentrations of Cyfra 21-1, TPA, and TPS concentrations were significantly higher than serum concentrations (p < 0.01). Serum Cyfra 21-1, TPA, and TPS concentrations were significantly lower in controls and in those with chronic bronchitis than in patients with epidermoid and nonepidermoid carcinoma (p < 0.01). No difference in serum concentrations of the three markers was observed between controls and patients with chronic bronchitis. On the contrary, BW Cyfra 21-1 and TPA concentrations were significantly higher in those with chronic bronchitis and in cancer patients than in controls (p < 0.01), whereas they did not differ between patients with chronic bronchitis and cancer patients. No significant difference in BW TPS concentration was observed among the four groups. Sensitivity and specificity of the BW markers in diagnosing lung cancer were as follows: 68.4% and 61.9% for Cyfra 21-1; 68.4% and 66.6% for TPA; and 57.9% and 66.6% for TPS.

CONCLUSIONS

BW fluid concentrations of Cyfra 21-1 and TPA are increased in patients with chronic bronchitis and in patients with lung cancer. Being unable to distinguish malignant from nonmalignant inflammatory conditions, the measurement of airway concentrations of such markers has a too-low specificity to be considered useful in diagnosing malignant abnormalities of the lung.