Analysis Of The Correlation Between TTF-1、CgA And PFS In Small Lung Cancer

Background and Objective: At present, lung cancer has become one of the most common malignant tumor in China. Its incidence rate and mortality rate rank first among various malignant tumours. Lung cancer can be divided into small cell lung cancer(SCLC)and non small cell lung cancer(NSCLC). Among them, small cell lung cancer is a neuroendocrine carcinoma which is easy to spread early. It grows rapidly and has a highly invasive ability, and its occurrence rate is on the rise. The present research has indicated that the immunohistochemical markers of thyroid transcription factor-1(TTF-1) and chromogranin A(CgA) can be helpful for the clinical diagnosis and differential diagnosis in SCLC. The research is a retrospective study. In order to explore the correlation beween the expression level of TTF-1、CgA and the progression-free survival(PFS) of small cell lung cancer, we have analysed the clinical characteristics and the expressions of TTF-1、CgA in97 cases of SCLC. By the meas of exploring the correlation,we can provide important reference for predicting the PFS of SCLC patients who have been treated by first-line standard chemotherapy, and guide early treatment for small cell lung cancer patients.Materials and methods: Collect 97 cases of SCLC patients with clinical data from January 1, 2009 to December 31, 2013 at Second Hospital Affiliated to Dalian Medical University, who have been diagnosed by pathological examination of fiexible bronchofiberscope biopsy or percutaneous lung puncture biopsy. They have been detected by immunohistochemical method and treated by the first-line chemotherapy. We analyse the general clinical data(age, sex, smoking history, staging, Karnofsky score and NSE level)and the expressions of TTF-1 and CgA in the 97 cases of SCLC. And PFS have been followed up by medical record review and telephone. Then the database are established for data analysis by SPSS17.0. Analysing the correlation of TTF-1、 CgA and PFS of SCLC patients through the univariate and multivariate analysis. All quantitativedata are expressed with mean±standard deviation which are analysed by t test. All continuous measures are expressed with integer which are analysed by chi-square test and rank sum test. The analysis of correlation are analyzed by bivariate analysis. Kaplan-Meier method is used to analyse survival, including the median survival and the confidence interval(CI). The log-rank method is used to evaluate the statistical significance between different group. The method of multivariate analysis is Cox regression model. In various statistical analysis methods, P < 0.05 is considered statistically significant.Results: 1. Expression of TTF-1 and CgA in the SCLC organizationIn 97 cases of SCLC patients, the positive expression of TTF-1(+~+++), 76 cases,negative expression(±~-), 21 cases; the positive expression of CgA(+~++), 52 cases,negative expression(±~-), 45 cases. The positive expression rate of TTF-1 and CgA are78.35% and 53.61%, respectively.2. The correlations between Expression of TTF-1 and CgA and general clinical data in SCLC patientsThere are no correlation between the expression level of TTF-1 and CgA and the age,sex, smoking history, staging, Karnofsky score and NSE levels, and no statistically significant(P > 0.05).3. The correlations between the expression of TTF-1 and CgA and clinical data and PFS in SCLC patients3.1 The expression of TTF-1 and CgA are closely related to the PFS in SCLC patients.The PFS are significantly longer in patients whose TTF-1 expression are positive than patients whose expression are negative(P < 0.05). The PFS are significantly longer in patients whose CgA expression are negative than patients whose expression are positive(P< 0.05). The PFS are significantly longer in the group of CgA/TTF-1(-/+) than the other three groups of CgA/TTF-1(- /-), CgA/TTF-1(+ / +) and CgA/TTF-1(+ /-). And there isstatistically significant(P < 0.05). There are no significant differences in the other three groups(P > 0.05). It indicates that TTF-1 positive expression and negative expression of CgA are helpful for PFS in SCLC patients who have been treated by fist-line standard chemotherapy.3.2 The univariate analysis of age, sex, smoking history, staging, Karnofsky score,NSE level and PFS in 97 cases SCLC patients indicate that the stage(P=0.014), Karnofsky score(P=0.084) and NSE level(< 0.001) are closely related to PFS in SCLC patients. These factors associated with PFS are analysed by multivariate Cox-regression analysis. The results show that the expression level of TTF-1 and the NSE level have statistically significant(P < 0.05). It indicate that the expression level of TTF-1 and the level of NSE may be important factors which influence the recurrence and metastasis in SCLC patients who have been treated by fist-line standard chemotherapy.Conclusions: 1. Compared with patients with positive expression of TTF-1, patients with negative expression of TTF-1 exhibit increased PFS in SCLC patients who have been treated by first-line standard chemotherapy.2. Compared with patients with negative expression of CgA, patients with positive expression of TTF-1 exhibit increased PFS in SCLC patients who have been treated by first-line standard chemotherapy.3. The expression level of TTF-1 and the level of NSE maybe were significant predictors of the therapeutic effect of first-line standard chemotherapy and prognosis of SCLC patients.