Determination Of Serum Tumor Markers In Lung Cancer Diagnosis

Objective:Lung cancer is the most common worldwide, killing one of the largest number of malignant tumors, the incidence rate is also highest in the malignant growth of the first. Lung cancer is divided into small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC), including non-small cell lung cancer accounts for about 80% of the total number of lung cancer. The late stages of lung cancer, especially in patients with 5-year survival rate is very low, so raise the level of the early diagnosis of lung cancer on the prognosis of patients with timely treatment and monitoring play an important role. In the lung cancer diagnosis, the tumor marker (TW) research is very active. Tumor marker refers to the occurrence and proliferation in the tumor process,Produced by the tumor cells, or secreted and released into the blood, cells, body fluids, to reflect the existence and growth of a tumor substances. It has high efficiency, high sensitivity, convenient and easy to obtain the specimens, and trauma, etc., so detection, screening and identification of tumor markers in early diagnosis of lung cancer has been the focus of the study. In this study, comparing with other domestic and foreign scholars and using ROC curve to evaluate the value of tumor markers in lung cancer diagnosis and pathological classification, the significance of serum tumor markers cancer embryonic antigen (CEA), carbohydrate antigen (CA125, CA19-9, CA242, CA153), neuron-specific enolase (NSE) in lung cancer patients is analyzed and clear.Materials and Methods:,360 hospitalized patients between 2007 and 2009 who have a full set of tumor markers recorded were Collected,112 healthy people who have a physical examination, aged in 35-81 years old. Which confirmed by cytology or pathology of primary lung cancer were 169 people, aged 35 to 81 years,99 cases were male and female 70 cases; benign pulmonary diseases were 191 cases,102 cases of male and 89 cases of female, of which 76 cases of pneumonia,49 cases of chronic obstructive pulmonary disease,15 cases of bronchial asthma,11 cases of bronchiectasis,12 cases of tuberculosis pleurisy,15 cases of pulmonary fibrosis,8 cases of pulmonary embolism,5 cases of pulmonary tuberculosis; exclusion criteria: the same time, there are other parts of the tumor by the merger. Control group:normal volunteers were 112 cases of non-neoplastic diseases or suffering from lung disease, of whom 63 cases male,49 female, aged in 35-74 years old.The sex ratio among the three groups, with an average age there was no statistical difference. Methods:All collected serum tumor markers are used the number of Uni-Bio Science Co., Ltd. Shanghai multi-tumor marker protein chip detection system, a positive determination criteria:CEA> 5 ng/ml, CA125> 35 kU/L, CA19-9> 35 kU/L, CA15-3>35 kU/ L, CA242>20 kU/L, NSE>13.0 ng/ml. Sensitivity (true positive rate)= the number of tumor marker-positive cases in tumor group/the total number of cases in lung cancer group×100%, specificity (true negative rate)= tumor marker-negative cases of control group/the total number of cases in control group×100%. Youden index= true positive rate-false-positive rate (1-true negative rate). Positive likelihood ratio = true positive rate/false positive rate; negative likelihood ratio= false negative rate/ true negative rate. Positive predictive value:the total number of samples obtained positive test, the tumor sample group accounted for the percentage of the total number of positive test; negative predictive value:the total number of samples obtained in the negative test,samples of the control group accounts for the percentage of the total number of positive test. SPSS 13.0 software used for statistical analysis data, Measurement data and median with range, said groups were analyzed using non-parametric Kruskal-Wallis test. Count data compared by chi-square test, the rate of count data compared with the chi-square test. And single index use ROC curve analysis.Y-axis of ROC curve detect sensitivity(true positive rate)of targets, x-axis denotes the specificity(the false positive rate)of indicators, the size of area under the curve reflects the accuracy of diagnostic test, once area under the curve is less than 0.5,there is no diagnosis,the lower accuracy is found between 0.5 and 0.7, between 0.7 and 0.9, accuracy is good,The highest accuracy is above 0.9.Results:The levels of serum CEA, CA19-9, CA125, CA15-3, CA242 and NSE in lung cancer group were significantly higher than in benign pulmonary disease group. The level of serum CA125 is higher than the control group, the levels of serum CEA and CA242 in the lung cancer patients is significantly higher than levels in lung squamous cell carcinoma and small cell lung cancer patients, serum CA19-9, and the levels of NSE in lung cancer patients are higher than levels in lung squamous cell carcinoma patients, There were significant differences (P<0.05). The diagnosis of lung cancer tumor markers were high specificity, but sensitivity is not high; with Youden Index, ROC curve,we can see that CEA and CA242 have a good diagnostic of lung cancer; when the value of serum CEA and CA242 in the 10.5 ng/ml, and 34.3kU/L or above, its specificity for the diagnosis of lung cancer were 100% and 99%. For different pathological type,various tumor markers have different sensitivity, the sensitivity of CEA, CA19-9, CA125, CA15-3, CA242 in adenocarcinoma are higher than squamous cell carcinoma, small cell lung cancer and other cell types. The sensitivity of NSE in small cell lung cancer is higher than that in other tumor markers, Tumor markers combined detection can improve the sensitivity of lung cancer, but the specificity will be reduced accordingly, CEA, CA125,CA242 and CA19-9 combined detection is considered the best..Conclusion:The levels of serum CEA, CA19-9, CA125, CA15-3, CA242 and NSE in lung cancer group were significantly higher than in benign pulmonary disease group.the diagnosis of CEA and CA242 in lung cancer has a good accuracy, when the value of serum CEA and CA242 in 10.5 ng/ml, and 34.3kU/L or above, its specificity for the diagnosis of lung cancer were 100% and 99%. In different histological types of lung cancer, CEA and CA242 can be used as identification of lung adenocarcinoma, and we do further study for the ability of NSE as identify target to small cell lung cancer. Tumor markers can improve the sensitivity of lung cancer, but the specificity will be reduced accordingly, CEA, CA125, CA242 and CA19-9 combined detection is considered the best.