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

鳞状上皮细胞癌抗原水平新检测方法在宫颈癌、肺癌和头颈部癌鉴别诊断中的性能及临床表现

鳞状上皮细胞癌抗原水平在鳞状上皮细胞癌中通常升高。这项多中心研究评估了一种新的Elecsys^®鳞状上皮细胞癌检测的检测性能，该检测方法是以等摩尔方式测量血清鳞状上皮细胞癌抗原1和2的水平，并研究了鳞状上皮细胞癌抗原用于宫颈癌、肺癌和头颈部鳞状上皮细胞癌鉴别诊断的潜能。在欧洲三个研究中心进行了精确度和方法学比较实验。健康人群的参考区间使用来自欧洲和中国人群的样本确定的。鉴别诊断试验确定了鳞状上皮细胞癌抗原水平能否将宫颈癌、肺癌或头颈癌与表观健康的、良性的或其他恶性群组区分开来。根据95%特异性下的鳞状上皮细胞癌抗原水平计算出鳞状上皮细胞癌抗原医学截断值。9个分析浓度的重复性变异系数 < 5.3%，中间精密变异系数 < 0.3%。方法学比较显示，与Architect和Kryptor系统具有很好的相关性（斜率分别为1.1和1.5）。表观健康人群的第95百分位数的参考区间为2.3 ng/mL（95%置信区间：1.9-3.8；欧洲队列，n=153）和2.7 ng/mL（95%置信区间：2.2-3.3；中国队列，n=146）。最佳的鉴别诊断结果见于宫颈鳞状上皮细胞癌：受试者工作特征曲线分析显示鳞状上皮细胞癌抗原水平（2.9 ng/mL的医学截断值）鉴别宫颈鳞状上皮细胞癌（n=127）与表观健康女性（n=286；曲线下面积：86.2%；95%置信区间：81.8-90.6；灵敏度：61.4%；特异性：95.6%），良性疾病（n=187；曲线下面积：86.3%；95%置信区间：81.2-91.3；灵敏度：61.4%；特异性：95.0%）和其他宫颈癌（n=157；曲线下面积：78.9%；95%置信区间：70.8-87.1；灵敏度：61.4%；特异性：86.7%）。鳞状上皮细胞癌还可帮助鉴别诊断肺癌。Elecsys鳞状上皮细胞癌检测技术在宫颈鳞状上皮细胞癌的临床实践中表现出了良好的性能，适合用于鉴别诊断。

Technical and clinical performance of a new assay to detect squamous cell carcinoma antigen levels for the differential diagnosis of cervical, lung, and head and neck cancer

In squamous cell carcinoma, squamous cell carcinoma antigen levels are often elevated. This multi-center study evaluated the technical performance of a new Elecsys® squamous cell carcinoma assay, which measures serum squamous cell carcinoma antigen 1 and 2 levels in an equimolar manner, and investigated the potential of squamous cell carcinoma antigen for differential diagnosis of cervical, lung, and head and neck squamous cell carcinoma.Assay precision and method comparison experiments were performed across three European sites. Reference ranges for reportedly healthy individuals were determined using samples from banked European and Chinese populations. Differential diagnosis experiments determined whether cervical, lung, or head and neck cancer could be differentiated from apparently healthy, benign, or other malignant cohorts using squamous cell carcinoma antigen levels alone. Squamous cell carcinoma antigen cut-off levels were calculated based on squamous cell carcinoma antigen levels at 95% specificity. Repeatability coefficients of variation across nine analyte concentrations were ≤5.3%, and intermediate precision coefficients of variation were ≤10.3%. Method comparisons showed good correlations with Architect and Kryptor systems (slopes of 1.1 and 1.5, respectively). Reference ranges for 95th percentiles for apparently healthy individuals were 2.3 ng/mL (95% confidence interval: 1.9–3.8; European cohort, n = 153) and 2.7 ng/mL (95% confidence interval: 2.2–3.3; Chinese cohort, n = 146). Strongest differential diagnosis results were observed for cervical squamous cell carcinoma: receiver operating characteristic analysis showed that squamous cell carcinoma antigen levels (2.9 ng/mL cut-off) differentiate cervical squamous cell carcinoma (n = 127) from apparently healthy females (n = 286; area under the curve: 86.2%; 95% confidence interval: 81.8–90.6; sensitivity: 61.4%; specificity: 95.6%), benign diseases (n = 187; area under the curve: 86.3%; 95% confidence interval: 81.2–91.3; sensitivity: 61.4%; specificity: 95.0%), and other cervical cancers (n = 157; area under the curve: 78.9%; 95% confidence interval: 70.8–87.1; sensitivity: 61.4%; specificity: 86.7%). Squamous cell carcinoma may also aid in the differential diagnosis of lung cancer. The Elecsys squamous cell carcinoma assay exhibited good technical performance and is suitable for differential diagnosis of cervical squamous cell carcinoma in clinical practice.

Increased expression of EZH2 in Merkel cell carcinoma is associated with disease progression and poorer prognosis

Enhancer of zeste homolog 2 (EZH2) is a histone methyltransferase that affects tumorigenesis by epigenetic gene silencing. Merkel cell carcinoma (MCC) is a rare cutaneous neuroendocrine carcinoma that has a high risk of disease progression with nodal and distant metastases. Here, we evaluated EZH2 expression by immunohistochemistry in a cohort of 85 MCC tumors (29 primary tumors, 41 lymph node metastases, 13 in-transit metastases, and 2 distant metastases) with clinical follow-up. We show strong/moderate EZH2 expression in 54% of tumors. Importantly, weak expression of EZH2 in the primary tumor, but not nodal metastases, correlated with improved prognosis compared to moderate/strong EZH2 expression (5-year MCC-specific survival of 68% versus 22%, respectively, P=.024). In addition, EZH2 was expressed at higher levels in nodal metastases compared to primary tumors (P=.005). Our data demonstrate that EZH2 has prognostic value and may play an oncogenic role in MCC.

Model-independent evaluation of tumor markers and a logistic-tree approach to diagnostic decision support

Sensitivity and specificity of using individual tumor markers hardly meet the clinical requirement. This challenge gave rise to many efforts, e.g., combing multiple tumor markers and employing machine learning algorithms. However, results from different studies are often inconsistent, which are partially attributed to the use of different evaluation criteria. Also, the wide use of model-dependent validation leads to high possibility of data overfitting when complex models are used for diagnosis. We propose two model-independent criteria, namely, area under the curve (AUC) and Relief to evaluate the diagnostic values of individual and multiple tumor markers, respectively. For diagnostic decision support, we propose the use of logistic-tree which combines decision tree and logistic regression. Application on a colorectal cancer dataset shows that the proposed evaluation criteria produce results that are consistent with current knowledge. Furthermore, the simple and highly interpretable logistic-tree has diagnostic performance that is competitive with other complex models.

Intragraft Toll-like receptor profiling in acute renal allograft rejection

BACKGROUND

Experimental studies have shown potential for Toll-like receptor (TLR) profiling in renal allograft in predicting renal outcome after transplantation. Our goal was to determine if profiling of TLR1-10 and TLR-related genes could be used as a prognostic value for renal function and late clinical outcome after transplantation.

METHODS

TLR1-10, CD14, MD-2 and negative regulators Toll-interacting protein (TOLLIP) and single immunoglobulin domain IL-1R-related receptor were analysed in 36 biopsies from renal transplant recipients with acute rejection (AR) and in 14 biopsies from renal transplant recipients without rejection (NR). Analysis was performed by multiplex ligation-dependent probe amplification. TLR (-related) genes were correlated to Banff'07 classification, cellular influx, response to conventional anti-rejection therapy, renal function 12 and 24 months after rejection and graft loss.

RESULTS

mRNA levels of most TLRs were significantly higher in acute rejection while TOLLIP mRNA level was decreased. mRNA levels of TLR1/2/4/7/8 were highly accurate in distinguishing AR from NR. TLR mRNA levels correlated to inflammatory parameters according to the Banff'07 classification and to cellular influx. Elevated mRNA level of TLR3 in acute rejection was independent from infiltrating leukocytes. TLR (-related) genes were not correlated with response to conventional anti-rejection therapy. Splice variant TLR4r3 was associated with poor renal function 24 months after transplantation, and TLR1 appeared to be associated with graft loss.

CONCLUSION

The elevated mRNA levels of several TLRs in association with reduced mRNA levels of TOLLIP in renal transplant biopsies of patients with acute rejection indicate a pro-inflammatory state, which may contribute to uncontrolled inflammation.

Tumor markers in detection of lung cancer

The expression of biomarkers by lung cancers is useful in the diagnosis and clinical management of patients with lung cancer. Biomarkers provide insight into histogenesis, interrelationships, and biological behavior of lung tumors. This chapter presents data on lung cancer detection, involving some of the most studied and interesting lung cancer biomarkers to date-CYFRA 21-1, NSE, ProGRP, SCC, CEA, Tumor M2-PK, as well as markers in clinical application such as CRP, LDH, tumor-suppressor genes and oncogenes, CA125, CgA, NCAM, and TPA. Biomarker profiles in combination with fuzzy logic techniques have also been addressed. Serum markers used alone or in combination with other indices might play an important role in monitoring response to therapy in early detection of tumor reactivation in new treatment strategies as well as in secondary prevention.

Serum concentration of AMDL DR-70 for the diagnosis and prognosis of carcinoma of the tongue

The aim of this study was to discover the clinical value of the tumour marker AMDL DR-70 in a group of patients with cancer of the tongue. Serum concentrations of AMDL DR-70 were estimated by enzyme linked immuno-sorbent assay in 52 patients with carcinoma of the tongue and compared with 40 controls and 42 patients with benign lesions in the tongue. Thirty-nine patients with carcinoma of the tongue had results above 6 mg/L (75%), compared with 3/40 (7%) in healthy controls and 4/42 (10%) in those with benign tumours. The concentration of AMDL DR-70 in serum correlated significantly with 3-year survival.

A sensitive and rapid immunoassay for quantification of CA125 in human sera by capillary electrophoresis with enhanced chemiluminescence detection

In this paper we have presented a sensitive and rapid immunoassay (IA) method by capillary electrophoresis with an enhanced chemiluminescence detection system (CE-CL) based on the catalytic effects of horseradish peroxidase (HRP) on the luminol-hydrogen peroxide reaction. The conditions for the CL reaction and electrophoresis were systematically investigated using HRP as a model sample. The linear range from 2.5 x 10(-11) to 1.0 x 10(-9) mol/L (R = 0.999), and the detection limit of 1.0 x 10(-12) mol/L (signal-to-noise ratio = 3) for HRP were achieved using para-iodophenol as CL enhancer. The relative standard deviations of the migration time and peak area for 5.0 x 10(-10) mol/L HRP (n = 7) were 0.26 and 4.8%, respectively, using a CE system with a home-built CL detector. Under the optimal condition, the HRP-labeled CA125 antibody (Ab) and the Ab-antigen complex were well separated within 4 min by CE using a high-pH buffer (pH 10.20). The assay was successfully used for quantification of CA125 in human sera from health controls and patients associated with ovarian cancer, and the recoveries of the standard addition experiments were 93-109%. Our primary results demonstrated that IA based on CE-CL detection is a powerful tool for clinical diagnosis combined with these commercial IA kits.

Clinical value of p53, c-erbB-2, CEA and CA125 regarding relapse, metastasis and death in resectable non-small cell lung cancer

The prognostic value of p53 and c-erbB-2 immunostaining and preoperative serum levels of CEA and CA125 was investigated in a prospective multicentric study including 465 consecutive non-small cell lung cancer (NSCLC) patients with resectable tumors. Four end-points were used: lung cancer death, first relapse (either locoregional or metastasis), loco-regional recurrence and metastasis development. Standard statistical survival methods (Kaplan-Meier and Cox regression) were used. The specificity of the prognostic effect across different types of tumors was also explored, as had been planned in advance. Our results showed, once again, that pathological T and N classifications continue to be the strongest predictors regarding either relapse or mortality. Three of the studied markers seemed to add further useful information, however, but in a more specific context. For example, increased CEA concentration defined a higher risk population among adenocarcinomas but not among people with squamous tumors; and p53 overexpression implied a worse prognosis mainly in patients with well differentiated tumors. The analysis of type of relapse proved to be very informative. Thus, CA125 level was associated with a worse prognosis mainly related with metastasis development. Another interesting result was the influence of smoking, which showed a clear dose-response relationship with the probability of metastasis. For future studies, we recommend the inclusion of different endpoints, namely considering the relationship of markers with the type of relapse involved in lung-cancer recurrence. They can add useful information regarding the complex nature of prognosis.

Prognostic value of serum tumor markers in patients with lung cancer

BACKGROUND

The role of tumor markers in the diagnosis and prognosis of lung cancer is under investigation.

OBJECTIVES

The aim of this study was to investigate the diagnostic and prognostic significance of pre-therapeutic levels of various serum tumor markers, CYFRA 21-1, neuron-specific enolase (NSE), tissue polypeptide antigen (TPA), carcinoembryonic antigen (CEA), CA 125 and squamous cell carcinoma antigen (SCCAg), in patients with lung cancer.

METHODS

We studied 102 consecutive patients (mean age 65.2 +/- 11 years) with newly diagnosed lung cancer (96 males, 94%, with a mean age of 66.3 +/-10.5 years). All patients had a 5-year follow-up. Measurements of the serum tumor markers were performed on initial diagnosis.

RESULTS

Eighty-four patients (82%) had non-small-cell lung cancer (NSCLC) and 18 (18%) small-cell lung cancer (SCLC). From the 84 patients with NSCLC, 34 patients (33%) had squamous-cell lung cancer, 23 (22%) adenocarcinoma and 23 (22%) large-cell carcinomas. The overall median survival was 8.5 months. All SCLC patients had extensive disease with a median survival of 10.1 months and NSCLC patients of 8.4 months. Significant differences in the mean values of NSE and CYFRA 21-1 were observed between SCLC and NSCLC. In NSCLC, CYFRA 21-1, TPA, CA 125 and SCCAg serum levels were related to the stage of the disease at diagnosis, and CYFRA 21-1, NSE, TPA and CA-125 were related to a poor outcome. None of the above tumor markers was related to survival in the SCLC group.

CONCLUSION

CYFRA 21-1 and NSE may help to differentiate cell types in lung cancer patients. Also, CYFRA 21-1 with TPA and CA 125 may provide useful information regarding the staging of the disease at diagnosis and the prognosis of patients with NSCLC.

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.

Use of tumor markers for differential diagnosis of mesothelioma and secondary pleural malignancies

STUDY OBJECTIVE

The aim of the study was to assess diagnosis value of tumor markers for differential diagnosis between mesothelioma and other pleural tumors.

DESIGN AND METHODS

Prospective study of 85 patients attending our hospital with malignant pleural effusion. The diagnostic approach involved routine pleurocentesis followed by pleural needle. When precise diagnosis was not achieved, thoracoscopy with pleural biopsies was performed. Carcinoembryonic antigen (CEA), hyaluronic acid, tissue polypeptide antigen and cyfra 21 to 1 were measured in serum and pleural fluid.

RESULTS

By using receiver operating characteristics curves and area under curves, the best diagnostic characteristics were obtained with pleural and serum CEA concentrations. The area under the curve was larger for pleural ACE than for serum ACE. The sensitivity and specificity of a pleural CEA level exceeding 3 ng/mL for ruling out the diagnosis of mesothelioma were 100% and 77%, respectively.

CONCLUSION

A CEA level above 3 ng/mL in pleural fluid eliminated the diagnosis of mesothelioma, whereas the other markers were not sufficiently discriminant. However, despite a negative predictive value of 100% at a cutoff of 3 ng/mL, CEA assay in pleural fluid only avoids a small number of diagnostic thoracoscopies.