Preliminary Study On The Value Of SHOX2,RASSF1A Methylation And Telomerase Activity In Bronchoalveolar Lavage Fluid In Differential Diagnosis Of Benign And Malignant Pulmonary Nodules

Objectiv:To study the clinical significance of SHOX2,RASSF1 A methylation and telomerase activity in bronchoalveolar lavage fluid in differential diagnosis of benign and malignant pulmonary nodules.Methods:1.Subjects: Patients with pulmonary nodules diagnosed in Northern Jiangsu People's Hospital from September 2018 to January 2020 were selected and examined by fiberoptic bronchoscopy,there were 38 patients with definite pathology,including 27 patients with malignant pulmonary nodules(lung cancer)and 11 patients with benign pulmonary nodules.Patients with benign pulmonary nodules were taken as the control group.2.Methods: The clinical data,laboratory examination and pathological results of the patients were collected,and the bronchoalveolar lavage fluid was collected,and the precipitated cells were collected after centrifugation,which were used for cytological analysis,PCR method to detect SHOX2 and RASSF1 A methylation,and PCR-ELISA method to detect telomerase activity.3.Statistical analysis: The data were analyzed by SPSS26 statistical software.Chi-square test was used to analyze the difference of SHOX2,RASSF1 A methylation and telomerase activity in BALF between benign and malignant pulmonary nodules.ROC curve was used to analyze the sensitivity,specificity and AUC of SHOX2,RASSF1 A methylation,telomerase activity,cytological analysis and serum carcinoembryonic antigen in the malignant pulmonary nodules(lung cancer).There was statistical significance(p < 0.05).Results :1.The positive rates of SHOX2,RASSF1 A methylation and telomerase activity in malignant pulmonary nodules were higher than those in benign pulmonary nodules.There was statistical significance(p<0.05).2.Diagnostic effect: The combined diagnosis of SHOX2 and RASSF1 A gene methylation(sensitivity: 70.4%,specificity: 81.8%,AUC: 0.761)in BALF is better than that of single gene methylation.The diagnostic sensitivity of telomerase activity in BALF was 74.1%,and the specificity was 72.7%,AUC:0.734.The diagnostic effect of the combination of methylation of two genes and telomerase activity in BALF was better than that of BALF cytological analysis(sensitivity: 25.9%,specificity: 100.0%,AUC: 0.630)and serum CEA(sensitivity: 7.4%,specificity: 90.9%,AUC: 0.492).Telomerase activity combined with cytological analysis(sensitivity: 77.8%,specificity: 72.7%,AUC: 0.753),combination of methylation of two genes and cytological analysis(sensitivity: 77.8%,specificity: 81.8%,AUC: 0.798)significantly improved the diagnostic effect.In the joint detection of multiple indicators,the combination of two genes methylation + telomerase activity + cytological analysis had the highest sensitivity and the best diagnostic effect(sensitivity:92.6%,specificity:72.7%,AUC:0.827).Conclusion:1.The positive rates of SHOX2 and RASSF1 A gene methylation and telomerase activity in bronchoalveolar lavage fluid(BALF)in patients with malignant pulmonary nodules(lung cancer)were significantly higher than those in patients with benign pulmonary nodules.2.The combined detection of methylation of SHOX2 and RASSF1 A genes,telomerase activity and cytological analysis in bronchoalveolar lavage fluid is the best in the diagnosis of benign and malignant pulmonary nodules.Themethylation combination of SHOX2 and RASSF1 A genes in bronchoalveolar lavage fluid and telomerase activity detection may be good indicators for differential diagnosis of benign and malignant pulmonary nodules and effective supplementary means for cytological analysis of bronchoalveolar lavage fluid.