Clinical usefulness of serum assays of neuron-specific enolase, carcinoembryonic antigen and CA-50 antigen in the diagnosis of lung cancer

Relationship between serum tumor markers and Anaplastic Lymphoma Kinase mutations in stage IV lung adenocarcinoma in Hubei province, Central China

Objective

The aim of this study was to explore the predictive value of carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCCAg), and neuron‐specific enolase (NSE) in the prediction of anaplastic lymphoma kinase (ALK) mutations in advance stage non‐small cell lung cancer (NSCLC).

Subjects and Methods

A total of 482 cases with untreated lung adenocarcinoma were retrospectively reviewed. Finally, 72 patients with stage IV were enrolled because of intact data of the detection of ALK rearrangement and serum tumor markers, as well they have not received any previous anticancer therapy. We used the one‐way ANOVA analysis, correlation analysis, and multiple logistic regression analysis to evaluate the relationship between the level of serum tumor markers and ALK mutations.

Results

Fifteen cases with ALK mutations and 57 cases without mutations were identified. The result of the one‐way ANOVA analysis showed only CEA was significantly associated with ALK mutations (95% CI:39.05‐148.88; P = .001). The area under the ROC curve (AUC) of CEA was 0.705 (95%CI:0.567‐0.843; P = .015). However, no significant association was observed between CEA and ALK mutations though the result of correlation analysis (P = .069) and multivariate logistic regression analysis (OR = 0.988, 95% CI: 0.972‐1.003, P = .111).

Conclusions

In our study, we performed on the patients with stage IV lung adenocarcinoma in our region and found preoperative serum levels of SCCAg, CYRF21‐1, and NSE not suitable for the detection of ALK mutation. Although we observed a significant association between CEA and ALK mutations; however, it was not strong enough to distinguish ALK status for the patients in our region.

Clinical significance of circulating tumor cells and tumor markers in the diagnosis of lung cancer

Background

Lung cancer has the highest fatality rate of all cancer types. To improve patients’ survival and life quality, it is therefore very important to screen for and detect it at an early stage.

Methods

A negative enrichment–fluorescence in situ hybridization (NE‐FISH) approach was used to detect circulating tumor cells (CTCs) in lung cancer patients, and levels of lung cancer‐associated serum markers were also measured in the peripheral blood of these same patients. The correlation between CTCs, serum cancer markers (carcinoembryonic antigen [CEA], CA 125, CYFRA 21‐1, and SCC), and clinicopathological characteristics was then investigated. Moreover, the potential clinical use of the combination of CTCs and tumor markers for the diagnosis of lung cancer, especially at early stages, was also explored.

Results

CTC frequencies in lung cancer patients were significantly higher than in healthy control volunteers or patients with benign lung disease, and the area under the receiver operating characteristics curve for the control group was 0.846 (95% CI 0.796‐0.887, P < 0.001). The rate of CTC positivity in lung cancer patients was 68.29% when the CTC cutoff value was 2, and the sensitivity of this means of lung cancer detection rose to 82.93% by combining CTC‐based detection with measurements of serum tumor markers. Similarly, the diagnostic sensitivity of this approach in early‐stage lung cancer patients (I‐II) was improved from 63.93% to 78.69%. Detection of CTCs can thus assist with the identification of benign and malignant pulmonary nodules.

Conclusions

It is potentially helpful and effective to employ a combination of CTCs and serum tumor markers for the clinical diagnosis of lung cancer.

Neuron-Specific Enolase

The clinical value of neuron-specific enolase as a marker in small cell lung cancer, neuroblastoma, melanoma and seminoma has been reviewed The role of serum and cerebrospinal NSE in benign and malignant disease of the central nervous sytem is discussed.

Preoperative CEA, NSE, SCC, TPA and CYFRA 21.1 Serum Levels as Prognostic Indicators in Resected Non-Small Cell Lung Cancer

In 62 patients affected by resectable non-small cell lung cancer (NSCLC) submitted to radical surgery we evaluated the prognostic significance of CEA, NSE, SCC, TPA and CYFRA 21.1 serum levels at diagnosis, as well as the predictive ability of these tumor markers with respect to histological type and pathological stage. The group was composed of 56 male and 6 female patients; the median age was 62 years (range 29–73 years). Thirty-four patients had a histological diagnosis of adenocarcinoma and 28 of squamous cell carcinoma; with regard to pathological stage, 32 patients had stage I, 4 patients stage II and 23 patients stage IIIA disease. A good predictive ability with respect to histological type was obtained with SCC serum levels; as for pathological stage, TPA and CYFRA 21.1 were found to have moderate predictive ability. In this series of patients, at a median follow-up of 55 months after surgery, we found that both TPA and CYFRA 21.1 serum levels at diagnosis were reliable predictors of overall survival, high values of these markers being associated with a worse prognosis.

The level of serum carcinoembryonic antigen is a surrogate marker for the efficacy of EGFR-TKIs but is not an indication of acquired resistance to EGFR-TKIs in NSCLC patients with EGFR mutationsm

The aim of the present study was to define the relationship between carcinoembryonic antigen (CEA) and survival in non-small cell lung cancer (NSCLC) patients receiving epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) and to investigate whether the level of serum CEA is related to the mechanism for acquisition of resistance to EGFR-TKIs. A total of 100 patients with advanced NSCLC (stage IIIB or stage IV) and harboring EGFR mutations were included. All patients received erlotinib or gefitinib treatment. The correlation between CEA serum level and clinical benefit from erlotinib or gefitinib treatment was analyzed. Patients were appraised by a review of data from a prospective re-biopsy protocol for lung cancer patients with an EGFR-mutated phenotype with acquired resistance to EGFR-TKI therapy. Of 100 patients, 49 and 21 patients carried high and low level of CEA, respectively; 30 carried normal CEA. Median progression-free survival was 6.4 and 4.5 months in patients with high and low level of CEA, respectively (P=0.027). Median PFS of patients in low-CEA group longer than that of those with normal level of tumors (3.0 months; P=0.002). The difference between groups L and N was not significant regarding objective response rate and overall survival. No significant difference was found in three groups of acquired resistance to EGFR-TKIs. The relative CEA level could predict benefit of EGFR-TKI therapy in advanced NSCLC, but could not predict acquired resistance to EGFR-TKIs.

Clinical evaluation and cost-effectiveness analysis of serum tumor markers in lung cancer

The detection of serum tumor markers is valuable for the early diagnosis of lung cancer. Tumor markers are frequently used for the management of cancer patients. However, single markers are less efficient but marker combinations increase the cost, which is troublesome for clinics. To find an optimal serum marker combination panel that benefits the patients and the medical management system as well, four routine lung cancer serum markers (SCCA, NSE, CEA, and CYFRA21-1) were evaluated individually and in combination. Meanwhile, the costs and effects of these markers in clinical practice in China were assessed by cost-effectiveness analysis. As expected, combinations of these tumor markers improved their sensitivity for lung cancer and different combination panels had their own usefulness. NSE + CEA + CYFRA21-1 was the optimal combination panel with highest Youden's index (0.64), higher sensitivity (75.76%), and specificity (88.57%), which can aid the clinical diagnosis of lung cancer. Nevertheless, the most cost-effective combination was SCCA + CEA, which can be used to screen the high-risk group.

Combining multiple serum biomarkers in tumor diagnosis: A clinical assessment

The present study aimed to assess the diagnostic/prognostic value of various clinical tumor markers, including carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), cytokeratin 19 (CYFRA21-1), α-fetoprotein (AFP), carbohydrate antigen-125 (CA-125), carbohydrate antigen-19.9 (CA-19.9) and ferritin, individually or in combination. The electro-chemiluminescence immunization method was performed to detect the levels of seven tumor markers in 560 cancer patients and 103 healthy subjects for comparison. The serum levels of the seven markers measured in cancer patients were higher compared to healthy subjects (P<0.05 for AFP and P<0.001 for the remaining six markers). Different markers had different sensitivity towards different types of tumors. Combining more markers significantly increased the ratios of positive diagnosis in the tumors. The diagnostic sensitivities of combining seven markers were particularly high in digestive, urinary and skeletal tumors (82, 92 and 83%, respectively). Gynecological tumors have exhibited a constant yet relatively low positive diagnosis irrespective of the use of a single marker or combined markers. However, the increase in sensitivity when combining markers was accompanied by a decrease in specificity. Generally, combining more markers increased the tumor detection rates, while a combination of the seven markers provided the highest detection rate. Combined detection showed a particularly high sensitivity in detecting respiratory, digestive and urinary system tumors, with the lowest sensitivity observed in gynecological tumors. As a result, combining tumor markers may play an important role in early tumor detection/diagnosis while the loss of specificity can be tolerated.

CEA levels in serum and BAL in patients suffering from lung cancer: correlation with individuals presenting benign lung lesions and healthy volunteers

BACKGROUND

Carcinoembryonic antigen (CEA) is a tumor marker belonging to the immunoglobulin gene superfamily of adhesion molecules. CEA is synthesized by epithelial and tumor cells. In this study, CEA levels in sera and bronchoalveolar lavage fluid (BAL) were measured in patients with malignant lung cancer and benign lung diseases.

METHODS

In the present study CEA was measured in serum using IRMA methods and in bronchoalveolar lavage of individuals undergoing fiberoptic bronchoscopy. Fifty patients with lung cancer (G1), 20 patients with benign lung lesions (G2), and a control group consisted of 20 individuals (G3) were enrolled in the study.

RESULTS

We found that serum CEA levels were significantly higher in G1 compared to G2 and G3 (p < 0.01). No significant difference in serum CEA levels was found between smokers and nonsmokers in any of the three groups studied. CEA was significantly higher in G1 BAL (p < 0.05) compared to G2 and G3 BAL. Furthermore, a statistically significant difference was found in CEA levels in BAL between smokers and nonsmokers of G2.

CONCLUSIONS

CEA levels in BAL of normal individuals may be influenced by smoking and other factors that affect lung epithelial cell function. Thus, CEA measurement in BAL alone has little value in the diagnosis of malignancy. BAL CEA levels in smokers of G2 are found significantly higher compared with nonsmokers of the same group and healthy individuals. Smokers of G2 have to be followed up carefully for the possibility of lung cancer growth.

Relationship between matrix metalloproteinase 2 and lung cancer progression

BACKGROUND AND OBJECTIVE

Matrix metalloproteinases (MMPs) play an important role in several steps of cancer development. MMP2 and MMP9 have previously been implicated in lymphatic and vascular invasion of lung cancer; however, the expression and prognostic significance of MMP2 and MMP9 is not fully clarified. This study was designed to investigate the significance of MMP2 and MMP9 in lung cancer tissue or serum, and their correlation with lung cancer prognosis.

METHODS

Immunohistochemical analysis was performed to determine MMP2 and MMP9 staining in human nonsmall cell lung cancer (NSCLC). Serum MMP2 and MMP9 protein levels in patients after surgery were measured using the ELISA method. The correlation between MMP2 and MMP9 serum levels and clinicopathological features of NSCLC were analyzed by survival analysis. We also performed reverse transcriptase (RT)-PCR assays to detect messenger RNA (mRNA) expression to further confirm the activity of MMP2 and MMP9 in human lung cancer.

RESULTS

Increased MMP2 immunostaining and MMP2 serum level correlated with advanced tumor stage and the presence of distant metastasis (Pearson's chi(2) test and ANOVA, p < 0.05). However, for MMP9, only serum level showed a correlation with advanced tumor stage. No significant correlation was observed between MMP2 or MMP9 immunostaining expression and tumor histologic features (Pearson's chi(2) test, p = 0.061 and p = 0.087, respectively). A high densitometry value of MMP2 and MMP9 PCR products (i.e. mRNA expression level) was related to poor differentiation grade, distant metastasis, and small cell carcinoma histologic type (ANOVA, p < 0.05).

CONCLUSIONS

Our results suggest that MMP2 is a more sensitive predictor than MMP9 of lung cancer progression, metastasis, and survival. Serum MMP2 levels may be a valuable prognosis variable and could help to stratify lung cancer patients into low- and high-risk groups.

Identifying patients at risk of early postoperative recurrence of lung cancer: a new use of the old CEA test

BACKGROUND

In the current study, we report the carcinoembryonic antigen (CEA) capability to predict early tumor relapses after a pulmonary resection for nonsmall cell lung cancer (NSCLC).

METHODS

We studied 118 consecutive NSCLC patients who were clinically judged operable and were eventually operated upon. Anthropometric, clinical, and CEA data along with the results of both preoperative and postoperative stage classifications were recorded. All patients were followed up for at least 1 year after surgery and the time to the first clinical recurrence recorded. Receiver-operating characteristic (ROC) curves and diagnostic formulas were used for data analysis.

RESULTS

In this series the CEA test was among the most accurate methods to predict an early postoperative recurrence (ROC area: 0.72, 95% confidence interval [CI]: 0.60 to 0.85, p = 0.001; accuracy rate for CEA at the threshold of 10 ng/mL: 83%, CI: 76% to 90%). Also predictive was the postoperative pathologic stage of disease (ROC area: 0.68, CI: 0.56 to 0.80, p = 0.007). In tumors pathologically classified in stage Ia to IIb, a preoperative CEA level higher than 10 ng/mL was associated with a 67% probability of tumor relapse. In the same stages of disease, a CEA level less than 10 ng/mL increased the baseline probability of no recurrence from 80% to 88%.

CONCLUSIONS

In operable patients with NSCLC the frequency of abnormal serum concentrations of CEA is low (17% in our series). However, it is important to identify such a small group of high-risk patients as many of them (in our study, 55% and 70% of those with a CEA value in excess of, respectively, 5 and 10 ng/mL) will develop an early postoperative recurrence. Such patients should be investigated preoperatively by mediastinoscopy or positron emission tomography in even in the absence of suspicious symptoms and signs. Then after an apparently successful operation, they should be carefully followed up. These patients could represent a suitable target for neoadjuvant clinical trials of selected high-risk groups.

Application of differential display to identify genes for lung cancer detection in peripheral blood

A blood assay for detection of lung cancer biomarkers could significantly improve cancer patient prognosis and survival rates. Amplified fragment length polymorphism-differential display (AFLP-DD) was used to identify gene transcripts found in lung cancer tissue and the peripheral blood of lung cancer patients. The clones were evaluated for gene expression in lung cancer tissue, peripheral blood of lung cancer patients and healthy volunteers' blood. The isolated gene transcript clones were found to be from the syndecan 1 gene, collagen 1 gene and 2 novel genes. All 4 transcripts were expressed in normal lung tissue, 4 cultured primary lung cells and 6 lung cancer cell lines. RNA was isolated from peripheral blood samples of 69 lung cancer patients. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to test for the presence of cytokeratin 19 and the 4 gene mRNA transcripts in blood RNA. The positive detection rate of at least 1 of the 5 transcripts was 79% for lung adenocarcinoma and 62% for squamous carcinoma. Using RT-PCR, at least 1 of the markers was found in 53% of stage I patients, 100% of stage II, 71% of stage III and 81% of stage IV lung cancer patients. Blood samples from 20 healthy volunteers were also tested, but only 1 of the 5 transcripts was found in 1 patient. These new molecular markers may aid early detection, staging and follow-up of lung cancer patients by RNA isolated from blood.

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.

An evaluation of the tumour markers, carcinoembryonic antigen (CEA), cytokeratin marker (CYFRA 21-1) and neuron-specific enolase (NSE) in the differentiation of malignant from benign solitary pulmonary lesions

PURPOSE

The aim of this prospective study was to assess the diagnostic value of the tumour markers carcinoembryonic antigen (CEA), cytokeratin 19 fragment marker (CYFRA 21-1) and neuron-specific enolase (NSE) in the differentiation of malignant (MSPLs) from benign solitary pulmonary lesions (BSPLs).

METHODS

Solitary pulmonary lesions (SPLs) were diagnosed using plain radiography and spiral computed tomography (SCT) and then completely removed by surgery in 104 consecutive patients (MSPLs; n = 81, BSPLs; n = 23). The serum concentrations of the tumour markers were determined 1-3 days prior to surgery by ELISA for CEA and CYFRA 21-1 and by IRMA for NSE using commercially available assay kits. The cut-off values were set at 3 ng/ml (for non-smokers) and 5 ng/ml (for smokers) for CEA, at 3.3 ng/ml for CYFRA 21-1 and at 12.5 ng/ml for NSE.

RESULTS

MSPLs were identified with a sensitivity between 13.6 and 45.7%, a specificity between 87.0 and 100% and an accuracy between 32.7 and 54.8%. Using the tumour markers alone, the highest sensitivity (27.2%) and accuracy (40.4%) was found with CEA, the highest specificity (100%) with CYFRA 21-1 and with NSE. Primary lung cancers (n = 39) were identified with a sensitivity between 17.9 and 61.5%, a specificity between 87.0 and 100% and an accuracy between 48.4 and 71.0%. Using the tumour markers alone, the highest sensitivity (35.9%) and accuracy (59.7%) was found with CYFRA 21-1, the highest specificity (100%) with CYFRA 21-1 and with NSE. The combination of all three tumour markers resulted in a greater sensitivity and greater diagnostic accuracy but a loss in specificity compared with CYFRA 21-1 and NSE.

CONCLUSION

The use of the tumour markers alone or in combination showed a low sensitivity and low accuracy for the diagnostic differentiation of MSPLs from BSPLs and primary lung cancers from BSPLs. However, both CYFRA 21-1 and NSE exhibited a specificity of 100% and may be useful complements to standard clinical imaging methods.

Tumor markers in lung cancer: does the method of obtaining the cut-off point and reference population influence diagnostic yield?

OBJECTIVES

The aim of this study was to evaluate the clinical usefulness of the tumor markers CA125, CEA, NSE, SCC, and TPS in a group of patients with lung cancer. We estimated the influence of the method for choosing the cut-off point and of considering as a reference population either healthy controls or patients with some form of non-neoplastic pulmonary disease (NNPD).

DESIGN AND METHODS

The tumor markers were determined using enzyme immunoassay techniques, and their diagnostic yield was evaluated using ROC curves and their correlation with the percentages between false and true positives. The diagnostic parameters of the tumor markers are presented in 116 patients with lung cancer and compared with a group of 25 healthy controls and another group of 80 patients with some form of NNPD. We determined on the one hand the cut-off points resulting from the best sensitivity-specificity balance in the ROC curves and on the other those resulting from considering a specificity of 95%. With the two cut-offs we studied the different diagnostic parameters: sensitivity, specificity and accuracy or area below the ROC curve.

RESULTS

Optimum diagnostic yield is obtained when we choose the cut-off point determined by the best balance of sensitivity and specificity in the ROC curves and take a healthy population as a reference group. The cut-off values for CA125, CEA, NSE, SCC, and TPS were 24 U/mL, 2.8 ng/mL, 9.8 ng/mL, 1.6 ng/mL, and 67.8 U/L, respectively.

CONCLUSIONS

Our results suggest that in future studies on tumor markers, a group of healthy subjects should be used as a reference population and ROC curves should be used to obtain the optimum cut-offs.

Clinical aspects of altered glycosylation of glycoproteins in cancer

Alteration of the expression of carbohydrate structures is frequently observed in tumor cells. This review summarizes the different changes of O- and N-linked glycoproteins observed in cancer cells, the impact of the tumor-related carbohydrate phenotypes on the clinical outcome of the cancer disease, and the various ways in which carbohydrate structures can interact with different carbohydrate-detecting adhesion molecules, selectins, and sialoadhesins. Various ways of inhibiting the formation of cell adhesion-engaged carbohydrates on the cell surface, or inhibiting the binding are discussed. Carbohydrate structures which are in clinical use as circulating tumor markers and the effect of genotypes on tumor marker concentrations are reviewed.

Clinical aspects of altered glycosylation of glycoproteins in cancer

Alteration of the expression of carbohydrate structures is frequently observed in tumor cells. This review summarizes the different changes of O- and N-linked glycoproteins observed in cancer cells, the impact of the tumor-related carbohydrate phenotypes on the clinical outcome of the cancer disease, and the various ways in which carbohydrate structures can interact with different carbohydrate-detecting adhesion molecules, selectins, and sialoadhesins. Various ways of inhibiting the formation of cell adhesion-engaged carbohydrates on the cell surface, or inhibiting the binding are discussed. Carbohydrate structures which are in clinical use as circulating tumor markers and the effect of genotypes on tumor marker concentrations are reviewed.

The usefulness of carcinoembryonic antigen testing in the overall management of patients with non-small-cell lung cancer

Carcinoembryonic antigen (CEA) testing is a valuable adjunct in the overall management of patients who have non-small-cell lung cancer, especially when selecting surgical candidates for curative lung resection and in cases where the diagnosis is in doubt. Carcinoembryonic antigen levels above 50 strongly suggest advanced-stage cancer and should discourage lung resections in otherwise suitable cases. Carcinoembryonic antigen testing can enhance problem solving in difficult cases and help prevent needless invasive interventions.

Peptide amidating activity in human bronchoalveolar lavage fluid

Monitoring respiratory epithelial biology may reveal individuals with incipient lung cancer. The expression of neuroendocrine (NE) markers in pulmonary epithelium is thought to be central to lung development, repair of injury and may contribute to carcinogenesis. In this study, we evaluate several candidate NE markers to determine the feasibility of prospective analysis of clinical specimens. The potential NE markers include the enzyme L-DOPA decarboxylase (DDC), the neuropeptide gastrin releasing peptide (GRP), and peptidyl-glycine alpha-amidating monooxygenase (PAM), the bifunctional enzyme responsible for the final bioactivation step of many neuropeptides. A comparison of PAM activity and DDC levels in 30 lung cancer cell lines indicated that peptide amidating activity may be an indicator of NE status. Bronchoalveolar lavage (BAL) fluid from subjects at risk of developing second primary lung cancer and from volunteers was obtained. The activity of the first PAM enzyme, peptidylglycine alpha-hydroxylating monooxygenase (PHM), ranged from not detectable to 507 pmol/h/mg protein in 57 specimens. The second PAM enzyme, peptidylamidoglycolate lyase (PAL), ranged from not detectable to 414 pmol/h/mg protein in 56 specimens. Using cluster analysis by the average linkage method, a group of enzyme values with PHM greater than 230 pmol/h/mg protein was determined. Long-term follow-up of these patients for new second primary lung cancers may help to determine the potential predictive value of PAM detected in the BAL fluid.

Serum neuron specific enolase (S-NSE) reference interval evaluation by time-resolved immunofluorometry compared with a radioimmunoassay

The serum neuron specific enolase (S-NSE; EC 4.2.1.11) reference interval was evaluated by DELFIA (Wallac) in 161 healthy blood donors and the method compared with the S-NSE RIA assay (Pharmacia). The DELFIA assay total analytical variation coefficient (CV%) was between 3.7% and 6.6%., the RIA CV% 7.6% to 13.1%. Late centrifugation (after hours) increased the variation as a result of contamination with blood cells. Log transformation into a gaussian distribution was selected by Box-Cox analysis and tested by two models: the gauss-distribution and the Refval transformation. The 95% reference intervals and corresponding 90% confidence intervals were: female 2.9-9.6 micrograms/l (2.6-3.2 and 8.5-10.7) micrograms/l and male 3.4-11.7 micrograms/l (3.0-3.8 and 10.2-13.2 micrograms/l). Mean values were significantly different (P < 0.001), female 5.3 (4.9-5.6), male 6.3 (5.8-6.7) micrograms/l. The serum NSE levels were analysed with both methods in a population of 110 patients. The results were significantly correlated (coefficient, 0.9896; r, 0.99; P < 0.0001-two tailed). For high S-NSE values (> 150.0 micrograms/l) differences between the methods exceeded the mean difference + 2S.D., while low concentrations were interconvertible. Maximal diagnostic efficacy was 0.91 for both assays, in DELFIA 17.2-23.9 micrograms/l and for RIA 17.2-21.9 micrograms/l. Identical sensitivity, specificity, discriminative power score, and likelihood ratio were found. The two methods are consequently interconvertible.

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.

Prediction of survival and recurrence by serum and cytosolic levels of CEA, CA125 and SCC antigens in resectable non-small-cell lung cancer

Risk of death and risk of recurrence in 108 potentially curable non-small-cell lung cancer patients were analysed with respect of TNM stage, histological type and carcinoembryonic antigen (CEA), CA125 antigen and squamous cell carcinoma antigen (SCC) levels in serum and cytosol. CA125 and CEA levels were closely related to outcome figures. Multivariate analyses indicated that TNM stage and histological type had the best predictive power, but serum and cytosolic CA125 and serum CEA contained additional, independent prognostic information. Predictive information drawn from serum and cytosolic levels proved mutually complementary. We conclude that CA125 and CEA complement TNM classification and histological type for the purpose of quantifying risk of death or recurrence.

Assessment of serum CYFRA 21-1 in lung cancer

BACKGROUND

Cytokeratins are the intermediate filaments of the cytoskeletal protein located in normal epithelia, tumor, and cultured cells. Recently, a fragment of cytokeratin subunit 19, referred to as CYFRA 21-1, detected in the serum of patients with nonsmall cell lung cancer, has been reported as a new tumor marker. This article reports the results of a study of serum fragment CYFRA 21-1, measured by immunoradiometric assay, as a marker of lung cancer.

METHODS

One hundred fourteen patients with primary lung cancer, 6 patients with malignant solid tumor, 116 patients with a variety of benign diseases, and 29 normal individuals were entered into the study. Serum CYFRA 21-1 levels were obtained by means of immunoradiometric assay using the CYFRA 21-1 EIA (enzyme immunoassay) kit. In addition, we studied other tumor markers, including carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC), and neuron specific enolase (NSE), as a means of lung cancer diagnosis.

RESULTS

The diagnostic accuracy and sensitivity of serum CYFRA 21-1 for the detection of lung cancer were highest among the four markers. The serum CYFRA 21-1 levels were most highly elevated in lung carcinoma patients (in particular UICC Stage IV patients) across different histologic types and attained 85.1% sensitivity when using a threshold of 3.5 ng/mL. The diagnostic sensitivity for detecting lung carcinoma was substantially enhanced by means of combined assays of CYFRA 21-1 with CEA overall for lung cancer, with SCC for squamous cell carcinoma, and with CEA for adenocarcinoma.

CONCLUSIONS

These findings suggest that serum assays of CYFRA 21-1 are clinically useful for the diagnosis of lung carcinoma.

Clinical evaluation of seven tumour markers in lung cancer diagnosis: can any combination improve the results?

In this study we compared the diagnostic utility of: (1) neuron-specific enolase (NSE); (2) squamous cell carcinoma antigen (SCC); (3) carcinoembryonic antigen (CEA); and (4) cytokeratin markers (CYFRA 21-1, TPA, TPM, TPS) in patients with small-cell lung cancer (SCLC) (21 cases) and non-small-cell lung cancer (94 cases). For comparison we also studied 66 patients with benign lung diseases and nine with pleural mesothelioma. NSE levels in SCLC patients were significantly higher than those in all the other groups studied. No significant variations were found among the SCC levels in all groups. CEA levels in patients with adenocarcinoma were significantly higher than those in all other groups studied. CYFRA 21-1 serum levels significantly increased in patients with squamous cell carcinoma and mesothelioma, while TPA, TPS and TPM increased in patients with lung cancer irrespective of the histological type. In patients with SCLC, high levels of all markers except SCC were found when the disease was extensive. In patients with non-SCLC, the highest levels of all tumour markers were usually found in those with advanced disease, although CYFRA 21-1 gave a sensitivity of 44% when a specificity of 95% was fixed in stage I non-SCLC patients. An analysis of receiver operating characteristic curves revealed that the highest diagnostic accuracies in distinguishing benign from malignant lung diseases were achieved with TPM (81%), CYFRA 21-1 (72%), CEA (78%) or TPA (78%) when using cut-off values of 46 Ul-1, 3.0 micrograms l-1, 2.0 micrograms l-1 and 75 Ul-1 respectively. When all patients were considered, the combined evaluation of more than one marker did not significantly improve the results obtained with TPM alone. However, taking into consideration the fact that CYFRA 21-1 is the most sensitive index of early lung tumours and that its combined determination with TPM did not worsen the overall sensitivity and specificity of the latter, the combined use of these two markers may be suggested as a useful took for the diagnosis of lung tumours.

Serological tumor markers for small cell lung cancer and their therapeutic implications

Serological tumor markers may become widely used as inexpensive and non-invasive methods of cancer detection. Markers of current interest for small cell lung cancer (SCLC) comprise enzymes, peptides, proteins, and carbohydrates. None of the serological markers for SCLC have yet proven to be of diagnostic value and at present their use is limited to monitoring disease and indicating prognosis. However, whilst serological markers related to the metabolic state of SCLC cells, such as neuron-specific enolase, serum thymidine kinase and tissue polypeptide antigen, may only be used for monitoring patients and for estimating prognosis, the other serological markers under current investigation may be used to indicate new treatment forms. Several novel approaches, including interference in the autocrine growth-regulating loop of SCLC by either peptides or antibodies, have been tried, SCLC is a highly heterogeneous tumor with respect to antigen expression, regulation of growth, and differentiation state. It is therefore important that new interventions are directed against both antigen-positive and antigen-negative tumor cells. For instance, radioisotopes or enzymes coupled to antibodies may be effective by exerting toxicity at some distance from the target. Antigens expressed on SCLC cells, such as peptide receptors involved in growth regulation, carbohydrate antigens like Lewis antigens, carcinoembryonic antigen and the ganglioside fucosylGM1, provide potential targets for antibody-conjugated therapy.

Quantitative analysis of carcinoembryonic antigen, squamous cell carcinoma antigen, CA 125, and CA 50 cytosolic content in non-small cell lung cancer

BACKGROUND

The cytosolic content of carcinoembryonic antigen (CEA), squamous cell carcinoma (SCC), CA 125, and CA 50 antigens in non-small cell lung cancer (NSCLC) is analyzed in this study. The aim was to ascertain the relationship between tumor marker content and the clinicopathologic aspects of this neoplasm.

METHODS

Lung tissue samples were obtained at the time of surgery from 75 patients with NSCLC patients (samples of tumor and unaffected tissue) and 29 subjects with idiopathic pneumothorax. All determinations were performed on cytosols obtained from lung specimens. CEA and CA 125 were determined by enzyme immunoassay, SCC antigen by radioimmunoassay, and CA 50 by fluoroimmunoassay. Tumor marker content was analyzed by TNM stage, histologic type, tumor grade, and number of atypias.

RESULTS

The concentration of the four markers was significantly higher in cytosol obtained from neoplastic tissue. Frequency of elevated levels of CEA was higher in adenocarcinoma (87% cases expressing high levels of the marker), SCC antigen in epidermoid carcinoma (65% expressing high levels), and CA 125 in large cell carcinomas (100% expressing high levels). No association was found between TNM stage and cytosol concentration for any of the four markers. CEA exhibited significantly greater concentration in well differentiated tumors, whereas this was true of CA 125 in poorly differentiated tumors. CA 125 content was higher in tumors with more atypia.

CONCLUSIONS

Cytosolic quantification of tumor markers may be an adjuvant mechanism to evaluate histologic subtypes of non-small cell lung cancer and identification of tumors with poorly differentiated features.

Prognostic significance of serum CA 125 antigen assay in patients with non-small cell lung cancer

BACKGROUND

The serum levels of CA 125 tumor-associated antigen in patients with lung cancer have been previously related to TNM stage, histologic type, and survival rate. In the current study, the prognostic information provided by the CA 125 antigen assay was analyzed.

METHODS

Preoperative serum of CA 125 antigen was determined in 137 patients with non-small cell lung cancer. The assay was performed by means of a solid-phase enzyme-immunoassay test. The influence of CA 125 serum level on postoperative outcome was studied by a multivariate analysis, performed with Cox's proportional hazards regression model.

RESULTS

Patients whose initial CA 125 level was higher than 15 U/ml had a 3.25-fold greater likelihood of relapse (95% confidence interval [CI], 1.7-6.21) (P < 0.001) and a 4.27-fold greater likelihood of deaths (95% CI, 2.42-7.55) (P < 0.001) due to cancer than patients with lower values. For patients with serum levels over 15 U/ml, the 36-month survival rate posttreatment was lower (67% versus 20%) (P < 0.001), as was the disease-free rate (64% versus 13%) (P < 0.001). After adjustment for TNM stages, histologic type, sex, and age, patients with CA 125 values over 15 U/ml continued exhibiting higher risk of relapse (hazard ratio, 2.2; 95% CI, 1.04-4.69) (P = 0.04) and higher risk of death (hazard ratio, 2.42; 95% CI, 1.29-4.54) (P = 0.006).

CONCLUSIONS

CA 125 is an independent prognostic factor of survival and tumor relapse in non-small cell lung cancer. The preoperative serum level of CA 125 antigen is inversely correlated with the outcome figures. The authors suggest that CA 125 be included in any future multifactorial analysis of survival.