Optimal Managements Of Stage ⅢA(N2)Non-small Cell Lung Cancer Patients

Lung cancer has become the worldwide leading cause of cancer-related mortality nowadays and non-small cell lung cancer(NSCLC)accounts for 80%of all lung cancers.□ Among patients with NSCLC,15%are diagnosed with stage IIIA.With the acknowledgement that mediastinal lymph node metastases(N2 staging)are□ associated closely with treatment and prognosis,the optimal management of stage IIIA-N2 NSCLC patients is unclear.Variable results of surgery versus radiotherapy after induction chemotherapy were reported.Nevertheless,despite surgical resection is radical and may lead to a survival bene t,whether the surgery is superior to radiotherapy still remains unclearFurthermore,the difficulty of accurate clinical staging challenges the treatment scenario of those patients in this stage.According to the 7th edition AJCC TNM staging,NSCLC patients with ipsilateral mediastinal and/or subcarinal lymph node(N2)diagnosed as IIIA stage include □ T1-T3(T3:tumor<7 cm)and MO(without distant metastasis).Moreover,the precise designation of mediastinal or subcarinal lymph node also plays the critical role in the classification.The false positive rate of the noninvasive staging reaches 25%to 40%,and it is recently reported that the clinical nodal overstaying rate is 43%.However,the invasive method such as mediastinoscopy or biopsy is done with varying frequency and effectiveness Therefore,the clinical stage evaluation of IIIA-N2 NSCLC patients is needed to be more precise and the issue whether IIIA(cN2)cases are resectable or unresectable(treated mainly with chemotherapy or radiation)is still controversialThe Surveillance,Epidemiology,and End Results(SEER)database of the National Cancer Institute provides information on cancer occurrences in 18 areas of United States and covers approximately 26%of the population.□ We perform this database study to evaluate the outcomes of patients treated with surgery,radiation,or both of them with different sequences.In addition,we investigate several relevant potential factors to clarify how they affect the outcome and hope to provide more information for clinical treatment decision-making.□We extracted patients diagnosed as NSCLC stage IIIA(cN2)between 2004 and 2011 from Surveillance,Epidemiology,and End Results(SEER)database.Overall survival(OS)and lung cancer-specific survival(LCSS)were compared among patients given different clinical managements by Kaplan-Meier method.Other variables such as age,sex and tumor size were analyzed to explore the factors associated with outcomes.A total of 98,700 IIIA-cN2 NSCLC patients were identified from SEER database.Survival of patients treated with surgery was better than that of patients treated by radiotherapy alone(P<0.001).Radiation prior to surgery significantly improved the survival in comparison with surgery alone(P<0.001).In the subgroups of OS analysis,age>65(P=0.902),adenocarcinoma(P=0.279),tumor size<3 cm(P=0.170),well differentiated(P=0.360)patients,preoperative radiotherapy improved survival insignificantly compared with surgery alone.Preoperative radiation with surgery had the most encouraging survival outcomes in stage IIIA-cN2 NSCLC patients compared with radiation or surgery alone.No significant outcome improvement was shown between postoperative radiotherapy(PORT)and surgery alone.