[Tumor markers in pleural effusions in bronchogenic carcinoma and tuberculosis]

Clinical Evaluation of Tumor Markers for Diagnosis in Patients with Non-small Cell Lung Cancer in China

BACKGROUND

To evaluate the value of combined detection of serum carcinoembryonic antigen (CEA), cytokeratin 19 fragment (CYFRA21-1), and carbohydrateantigen 125 (CA125) for the clinical diagnosis of non- small cell lung cancer (NSCLC).

MATERIALS AND METHODS

Serum CEA, CYFRA21-1 and CA125 were assessed in 140 patients with NSCLC, 90 patients with benign lung disease and 90 normal control subjects, and differences of expression were compared in each group, and joint effects of these tumor markers in the diagnosis of NSCLC were analyzed.

RESULTS

Serum CEA, CYFRA21-1 and CA125 in patients with NSCLC were significantly higher than those with benign lung disease and normal controls (P<0.05). The sensitivity of CEA, CYFRA21-1 and CA125 were 49.45%, 59.67%, and 44.87% respectively. As expected, combinations of these tumor markers improved their sensitivity for NSCLC. The combined detection of CEA+CYFRA21-1 was the most cost-effective combination which had higher sensitivity and specificity in NSCLC. Elevation of serum CEA and CYFRA21-1 was significantly associated with pathological types (P<0.05) and elevation of serum CEA, CYFRA21-1 and CA125 was significantly associated with TNM staging (P<0.05).

CONCLUSIONS

Single measurement of CEA, CYFRA21-1 and CA125 is of diagnostic value in the diagnosis of lung cancer, and a joint detection of these three tumor markers, could greatly improve the sensitivity of diagnosis on NSCLC. Combined detection of CEA+CYFRA21-1 proved to be the most economic and practical strategy in diagnosis of NSCLC, which can be used to screen the high-risk group.

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.

Selective killing of lung cancer cells using carcinoembryonic antigen promoter and double suicide genes, thymidine kinase and cytosine deaminase (pCEA-TK/CD)

The application of gene therapy in cancer treatment is limited by non-specific targeting. In the present study, we constructed a recombinant plasmid, containing a carcinoembryonic antigen (CEA) promoter and double suicide genes thymidine kinase (TK) and cytosine deaminase (CD), henceforth referred to as pCEA-TK/CD. Our results showed that the CEA promoter can specifically drive target gene expression in CEA-positive lung cancer cells. In the presence of prodrugs 5-flucytosine and ganciclovir, pCEA-TK/CD transfection decreased inhibitory concentration 50 and increased apoptosis and cyclomorphosis. Our result suggests that gene therapy using pCEA-TK/CD may be a promising new approach for treating lung cancer.

[Potential role of cholesterol in distinguishing malignant from benign pleural effusion]

Cholesterol and carcinoembryonic antigen (CEA) levels in pleural effusion and sera, were measured in 199 patients with pleural effusions of various origins. Malignant cause was found in 93, and nonmalignant in 106 patients. Mean cholesterol level in sera of patient with malignant disease was 5.0 +/- 0.93 mmol/L, and in nonmalignant group 4.34 +/- 1.32 mmol/L. The difference was not statistically significant. Mean cholesterol level in nonmalignant pleural effusions was higher thAn those in malignant (2.51 +/- 1.23 mmol/L; and 2.28 +/- 1.06 mmol/L), but the difference was also not significant. Average pleural fluid/serum cholesterol ratio (Holl/S) in nonmalignant group was 0.61 +/- 0.32 and in malignant group 0.46 +/- 0.22. The difference between those mean values was significant. Higher ratio, at the cut off value of 0.5 was found in 79/106 and in 25/93 malignant patients. Calculated sensitivity was 75%, specificity 73%, positive predictive value 76%, negative predictive value 65% and accuracy 69%. Significant negative correlation between Holi/S and pleural fluid CEA was found (p < 0.05). It was assumed that pleural fluid/serum cholesterol ratio lower than 0.5 could be of great benefit, as an additional test in the differentiation of malignant from benign pleural effusion.