Treatment Of Advanced Non - Small Cell Lung Cancer And The Exploratory Study Of Malignant Pleural Effusion - Specific Polypeptide Markers

Background:Non-small cell lung cancer is an agressive malignancy which has a very poor prognosis. Every year, the number of patients died of non-small cell lung cancer(NSCLC) is increasing. At present, due to the lack of target drugs, chemotherapy is still the standard treatment of advanced squamous lung cancer. The chemotherapy sequence, however, is unkown to our knowledge. What is more, there is still lacking biomarkers with high sensitivity and specificity for NSCLC. Nowadays, the rising proteomics technologies such as matrix-assisted laser desorption/ionization time of flight mass spectrometer(MALDI-TOF-MS) brings a lot of convenience for biomarker screening. Therefore, our study is aimed at sequential treatment and biomarkers screening in order to realize the best individual management of advanced NSCLC.Part oneObjective: Gemcitabine and taxanes are effective agents commonly used in advanced squamous lung cancer. The best treatment sequence, however, is unclear to our knowledge. So we conducted this retrospective study in order to compare the efficacy and toxicities of first- line Gemcitabine +/- platinum followed by second-line taxanes +/- platinum with the reverse sequence.Methods: We totally analyzed 105 patients with stage ⅢB-Ⅳ squamous lung cancer in our retrospective study. There were 49 patients receiving gemcitabine +/-platinum first-line followed by taxanes +/- platinum second-line(G-T group), and 56 patients receiving taxanes +/- platinum first- line followed by gemcitabine +/-platinum second- line(T-G group). The primary endpoint of the study was overall survival(OS), and the secondary endpoints included progression- free survival(PFS), object response rate(O RR), disease control rate(DC R) and toxicities.Results:(1)The median OS were 18.5 months in G-T group and 19.0 months in T-G group(P=0.520).(2)The media PFS1 was 5.0 months and 4.0 months with first line gemcitabine +/- platinum and taxanes +/- platinum, respectively(P=0.645). The media PFS2 was 2.7 months and 2.5 months with second line gemcitabine +/- platinum and taxanes +/-platinum.(P=0.432).(3)The ORR1 of G-T group and T-G group were 36.73% and 33.92%(P=0.577), and DCR1 were 79.59% and 89.29%(P=0.186); the ORR2 of G-T group and T-G group were 4.08% and 5.36%(P=0.085), and DCR2 were 51.02% and 66.07%, respectively(p=0.118).(4) The patients experienced more grade Ⅲ-Ⅳ lower hemoglobin(P=0.027) and thrombocytopenia(P=0.002) in G-T group through the whole study period. But there were more gradeⅠ/Ⅱgranulocytopenia(P=0.001) and grade Ⅳ thrombocytopenia(P=0.002) when treated with first- line gemcitabine +/- platinum, while the patients experienced more grade Ⅳ granulocytopenia(P=0.042) when treated with second- line taxanes +/- platinum.Conclusions: The efficacy of first line gemcitabine +/- platinum followed by second line taxanes +/- platinum and the reverse sequence was similar, and the toxicities were tolerable. Both sequential patterns were effective in advanced squamous lung cancer.Part twoObjective: In the second part of the study,we compare the peptide profiles between malignant pleural effusion(MPE) of adenocarcinoma and tuberculosis pleural effusion(TPE) based on MALDI-TOF-MS,so as to screen the biomarkers in malignant pleural effusion of lung cancer and establish a diagnosis classification to distinguish the malignant and benign pleural effusion.Methods:1. A total of 97 pleural effusions: 65 PE samples of NSCLC patients and 32 TPE samples were examed by cytological smear method.2. The 45 MPE samples diagnosed by cytological smear and 32 TPE samples were randomly assigned to training set and validation set according to the proportion of 2:1. In training set, the peptides of supernatant were isolated by weak cation exchange magnetic beads, and peptides peaks in the m/z range of 800–10000 Da were analyzed by MALDI-TOF-MS. Comparing the protein profile between 30 MPE and 22 TPE samples in training set by clinprotools software, we screened the specific biomarkers of MPE and established a MALDI-TOF-MS classification of MPE using the optimal algorithm embedded in the software. In order to verify the results, 15 MPE and 10 TPE samples were included as validation set which were analyzed by the same method.3. We additionally determined carcinoembryonic antigen(CEA) a part of MPE and TPE samples using electrochemiluminescent immunoassay method.4. We finally compared the MALDI-TOF-MS classification with cytological smear method and C EA examination.Results:1. In our study,a total of 65 PE of lung cancer patients were diagnosed by cytological smear method, and malignant cells were discovered in 45(69.23%) samples.2. The MALDI-TOF-MS identified 28 peptide peaks of statistical difference(P<0.05) when comparing the 30 MPE samples and 22 TPE samples of training set. Among the 28 peaks, 15 were higher, while the other 13 were lower in MPE samples of lung cancer than TPE samples. The clinprotools software selected 5 peptide peaks to construct the classification of MPE. The sensitivity, specificity and accuracy of the classification were 93.3%, 100%, 96% respectively after the blinded validation of the validation set.3. The sensitivity and specificity of C EA examination is 67.74%(21/31) and 71.87%(23/32).4. The positive rate of MALDI-TOF-MS classification is higher than cytological smear(P=0.013), and the sensitivity and specificity of our classification is equal to those of C EA examination without statistically different(P=0.07, P=0.086).Conclusions: There were peptide differences between the MPE samples of lung cancer and TPE samples, and the different peptide may be the protential biomarkers of lung cancer. The MALDI-TOF-MS classification of MPE in our study is of high sensitivity and specificity, and superior to standard cytological method. O ur MALDI-TOF-MS classification of MPE has the potential for clinical application due to its high sensitivity, specificity, and convenience.