PET/CT And EBUS-TBNA To Evaluate The Status Of N2 In Preoperative Non-small Cell Lung Cancer

Objective To investigate the diagnostic value of PET/CT and EBUS-TBNA in mediastinal lymph node N2 in patients with preoperative non-small cell lung cancer(NSCLC).Methods 112 patients with non-small cell lung cancer in our hospital January from 2015 to December 2016 are included in the retrospective analysis.The conditions of patients: 1,Chest CT showed lung lesions,and the final pathological diagnosis were non-small cell lung cancer.2,Chest CT prompted ipsilateral mediastinal lymph nodes,and short diameter>1cm.3,All patients with brain MR,chest and abdomen CT and body bone scan and other tests suggested no distant metastasis.4,All patients had no other tumor history,without fever,cough and sputum and other lung infection history,no tuberculosis history in recent.5,All patients had no thoracic invasive surgery history and no chemotherapy and other anti-tumor treatment before the test,incomplete clinical data were excluded.If mediastinal lymph node was diagnosed negative by EBUS-TBNA,the patient underwent thoracoscopic lobectomy and systemic intrathoracic lymphadenectomy to obtain pathological results.The results of PET/CT and EBUS-TBNA were compared with the final pathological results.And calculate their respective sensitivity,specificity,PPV,NPV and accuracy.Check whether there are differences comparing the effectiveness of two methods.Then the patients were divided into adenocarcinoma group and squamous cell carcinoma group according to the pathological type,and the results were calculated and compared with the above method.Results The sensitivity,specificity,PPV,NPV and accuracy of NSCLC mediastinal lymph node metastasis diagnosed by PET/CT were respectively 71.4%,60%,51.7%,77.8% and 64.3%.The sensitivity,specificity,PPV,NPV and accuracy of NSCLC mediastinal lymph node metastasis diagnosed by EBUS-TBNA were respectively 90.5%,100%,100%,94.6% and 96.4%.The results showed that EBUS-TBNA had a higher diagnostic value for mediastinal lymph nodes than in PET/CT,and the difference was statistically significant(p <0.001).In the adenocarcinoma group: the sensitivity,specificity,PPV,NPV and accuracy of NSCLC mediastinal lymph node metastasis diagnosed by PET/CT were respectively 65.2%,54.1%,46.9%,71.4% and 58.3%.The sensitivity,specificity,PPV,NPV and accuracy of NSCLC mediastinal lymph node metastasis diagnosed by EBUS-TBNA were respectively 91.3%,100%,100%,94.9% and 96.7%.The results showed that the sensitivity,specificity,PPV,NPV and accuracy of EBUS-TBNA were higher than that of PET/CT,and the difference was statistically significant(p <0.05).In squamous cell carcinoma,the sensitivity,specificity,PPV,NPV and accuracy of NSCLC mediastinal lymph node metastasis diagnosed by PET/CT were respectively 78.9%,66.7%,57.7%,84.6% and 71.2%.The sensitivity,specificity,PPV,NPV and accuracy of NSCLC mediastinal lymph node metastasis diagnosed by EBUS-TBNA were respectively 89.5%,100%,100%,94.3% and 96.2%.The sensitivity of EBUS-TBNA was greater than that of PET/CT,but the difference was not statistically significant(p=0.48).Both methods had higher NPV,but the difference was not statistically significant(p>0.05).EBUS-TBNA specificity,PPV,and accuracy were significantly higher than PET/CT,and the difference was statistically significant(p <0.05).Conclusion EBUS-TBNA was more accurate than PET/CT for preoperative diagnosis of mediastinal lymph node metastases in non-small cell lung cancer.EBUS-TBNA is an effective minimally invasive method after PET/CT scans.EBUS-TBNA was feasible,safe and effective as a method for the examination of mediastinal lymph nodes when it was positive diagnosed by PET/CT as a noninvasive method for the diagnosis of mediastinal lymph nodes in clinical stage IIIA patients with NSCLC.EBUS-TBNA could still help to confirm whether the mediastinal lymph nodes are really negative,when the patients were diagnosed mediastinal lymph node-negative by PET/CT,especially the patient’s pathologic type was adenocarcinoma.