***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: OBJECTIVES Since the introduction of video-assisted lobectomy for non-small-cell lung cancer ( NSCLC ) into clinical practice , it has been discussed controversially whether mediastinal lymphadenectomy can be performed as effectively as an open procedure via thoracotomy . Therefore , we address this issue in a prospect i ve r and omized trial conducted in our institution . METHODS In total , 66 patients with completely staged clinical Stage I NSCLC were included and r and omized either into a video-assisted group ( n = 34 ) or into the conventional lobectomy group ( n = 32 ) . The video-assisted thoracoscopic ( VATS ) lobectomy was performed by using a 4- to 5-cm utility incision in the fourth or fifth intercostal space and two additional 10-mm ports without rib spreading . The conventional lobectomy was done via an anterolateral thoracotomy . Lymph nodes were classified according to the International Association for the Study of Lung Cancer classification ; for right-sided tumours , lymph nodes number 2R , 4R , 7 , 8 , 9 , 10 , 11 and 12 were dissected , and for left-sided tumours , lymph nodes number 5 , 6 , 7 , 8 , 9 , 10 , 11 and 12 . For the subsequent analyses , lymph nodes were grouped into different zones consisting of Zone 1 ( 2R and 4R ) , Zone 2 ( 7 ) , Zone 3 ( 8R and 9R ) , Zone 4 ( 10R , 11 R and 12R ) , Zone 5 ( 4 L ) , Zone 6 ( 5 and 6 ) , Zone 7 ( 8L and 9L ) and Zone 8 ( 10 L , 11 L and 12L ) . RESULTS Both groups were comparable with respect to different clinical pathological parameters ( age , tumour size and comorbidity ) . In the video-assisted group , 2 patients were excluded due to conversion to an open thoracotomy . The number of mediastinal lymph nodes removed was as follows : VATS ( right side ) 24.0 lymph nodes/patient , open right-sided 25.2 lymph nodes/patient , VATS ( left side ) 25.1 lymph nodes/patient and open left-sided 21.1 lymph nodes/patient . With respect to the zones mentioned above , we found the following results : VATS vs open ( mean number of lymph nodes/patient ) : Zone 1 : 9 vs 8.5 ; Zone 2 : 6.3 vs 5.6 ; Zone 3 : 2.4 vs 3.2 ; Zone 4 : 6.5 vs 6.9 ; Zone 5 : 0 vs 0.5 ; Zone 6 : 3.2 vs 3.7 ; Zone 7 : 4.6 vs 3.2 and Zone 8 : 10.5 vs 8.9 . There were no statistically significant differences between the procedures , either with respect to the overall number of lymph nodes or with respect to the number of lymph nodes in each zone . CONCLUSIONS Mediastinal lymph node dissection can be performed as effectively by the video-assisted approach as by the open thoracotomy approach . Furthermore , the video-assisted approach allows a better visualization of different lymph node zones PURPOSE A major problem with the staging system for non-small cell lung cancer ( NSCLC ) is clinical underestimation of the extent of disease . Many patients with clinical stage 1 disease do not retain that design ation following surgical resection . Herein , we present data from Cancer and Leukemia Group B ( CALGB ) protocol 9761 evaluating the correspondence between clinical and pathologic analysis in early stage NSCLC . METHODS Five hundred and two patients with suspected or biopsy-proven NSCLC classified as clinical stage 1 ( T1 - 2 , N0 ) by computed tomography ( CT ) scan or cervical mediastinoscopy were prospect ively enrolled in CALGB 9761 . The purpose of CALGB 9761 was to prospect ively evaluate molecular markers of micrometastatic disease in stage 1 NSCLC . Enrollment occurred at 11 selected institutions within the CALGB . Patients with clinical ly suspected resectable early stage lung cancer were eligible for enrollment if they had no evidence of mediastinal or hilar adenopathy on CT scan or if they had CT evidence of potential N2 or N3 disease ( lymph node > or = 1.0 cm ) but with negative mediastinoscopy . No prior chemotherapy  or  radiotherapy  was permitted . RESULTS Of the 502 patients felt to have clinical stage 1 NSCLC enrolled in CALGB 9761 , 489 underwent resection with complete surgical staging and routine histopathologic analysis . From these 489 patients , only 422 ( 86.3 % ) turned out to have pathologically documented NSCLC . Of these 422 patients , 302 ( 71.6 % ) had pathologic stage 1 disease ( 173 stage 1A and 129 stage 1B ) . Despite clinical assessment of stage 1 disease , 59 ( 14 % ) patients had pathologic stage 2 disease , 57 ( 13.5 % ) had stage 3 disease , and four ( 0.9 % ) patients had stage 4 disease . Of the patients undergoing resection for clinical stage 1 NSCLC , 65 patients did not have NSCLC ( 44 had benign disease and 21 had malignancies other than NSCLC ) and two additional patients had dual synchronous primary NSCLC tumors and were not eligible for the study . Overall , only 61.7 % ( 302 of 489 ) of patients with suspected stage 1 NSCLC disease retained that stage and diagnosis after complete surgical staging , while 38.3 % had an inaccurate pre-operative clinical stage or diagnosis . CONCLUSIONS The results from this prospect i ve trial demonstrate the poor predictive value of current clinical staging techniques in early stage NSCLC . These findings will serve as a benchmark for comparison of future clinical imaging modalities and other tests evaluating early stage NSCLC OBJECTIVE Video-assisted thoracoscopic lobectomy remains controversial . We compared outcomes from participants in a r and omized study comparing lymph node sampling versus dissection for early-stage lung cancer who underwent either video-assisted thoracoscopic or open lobectomy .  METHODS Data from 964 participants in the American College of Surgeons Oncology Group Z0030 trial were used to construct propensity scores for video-assisted thoracoscopic versus open lobectomy ( based on age , gender , histology , performance status , tumor location , and T1 vs T2 ) . Propensity scores were used to estimate the adjusted risks of short-term outcomes of surgery . Patients were classified into 5 equal-sized groups and compared using conditional logistic regression or repeated measures analysis of variance . RESULTS A total of 752 patients ( 66 video-assisted and 686 open procedures ) were analyzed on the basis of propensity score stratification . Median operative time was shorter for video-assisted thoracoscopic lobectomy ( video-assisted thoracoscopy 117.5 minutes vs open 171.5 minutes ; P < .001 ) . Median total number of lymph nodes retrieved ( dissection group only ) was similar ( video-assisted thoracoscopy 15 nodes vs open 19 nodes ; P = .147 ) , as were instances of R1/R2 resection ( video-assisted thoracoscopy 0 % vs open 2.3 % ; P = .368 ) . Patients undergoing video-assisted thoracoscopic lobectomy had less atelectasis requiring bronchoscopy ( 0 % vs 6.3 % , P = .035 ) , fewer chest tubes draining greater than 7 days ( 1.5 % vs 10.8 % ; P = .029 ) , and shorter median length of stay ( 5 days vs 7 days ; P < .001 ) . Operative mortality was similar ( video-assisted thoracoscopy 0 % vs open 1.6 % , P = 1.0 ) . CONCLUSION Patients undergoing video-assisted lobectomy had fewer respiratory complications and shorter length of stay . These data suggest video-assisted thoracoscopic lobectomy is safe in patients with resectable lung cancer . Longer follow-up is needed to determine the oncologic equivalency of video-assisted versus open lobectomy BACKGROUND Video-assisted thoracoscopic surgery ( VATS ) for patients with early-stage non-small-cell lung cancer is associated with lower stress responses and potentially improved outcomes , as compared with thoracotomy . The goal of our study was to examine the cellular components of the postoperative immune response . Specifically , we assessed the cytotoxic capacity of peripheral blood mononuclear cells ( P BMC s ) of patients undergoing lobectomy for non-small-cell lung cancer by either VATS or thoracotomy . METHODS We performed a prospect i ve cohort study of lobectomy patients undergoing either VATS or thoracotomy .  We isolated P BMC s from perioperative blood sample s , and performed cytokine analysis on plasma fractions . Using flow cytometry , we analyzed P BMC phenotype ( CD3 , CD16/56 , CD4 , CD8 ) and T-cell activation markers ( CD25 , CD69 , HLA-DR ) . Using a chromium release assay , we quantified cellular cytotoxicity . To assess gene expression differences , we used Affymetrix messenger ribonucleic acid microarray and polymerase chain reaction analysis . RESULTS A total of 13 patients enrolled in our study : 6 , VATS ; 7 , thoracotomy . On postoperative day 1 , interleukin-6 and matrix metalloproteinase-9 were significantly different between the two groups . On day 2 , cellular cytotoxicity ( 0.34 ) was significantly greater ( p < 0.05 ) after VATS , as compared with thoracotomy ( 0.18 ) . In both groups , cytotoxicity returned to baseline and was equivalent at first follow-up ( VATS , 29.4 days versus thoracotomy , 29.3 days ; p > 0.05 ) . We noted minimal yet significant differences in P BMC phenotype , but no differences in T-cell activation makers . A 9-gene polymerase chain reaction-vali date d subset clustered the two groups with complete concordance . CONCLUSIONS Video-assisted thoracoscopic surgery lobectomy for non-small-cell lung cancer is associated with less impairment of cellular cytotoxicity , as compared with thoracotomy . We found that this difference was not accounted for by P BMC phenotypic changes . Instead , P BMC gene expression changes likely represent the molecular basis of this differential immune response BACKGROUND Video-assisted thoracic surgery ( VATS ) lobectomy for non-small cell lung cancer ( NSCLC ) is increasingly popular . However , the oncologic soundness of VATS for patients with NSCLC as measured by long-term survival has not been proven . The objective here is to determine the overall survival ( OS ) and disease-free survival ( DFS ) in two well-matched groups of patients with NSCLC resected by VATS or thoracotomy .  METHODS We conducted a retrospective review of a prospect i ve data base to identify patients who had a lobectomy for NSCLC . A propensity score-matched analysis was done with variables of age , sex , smoking history , Charlson comorbidity index , forced expiratory volume in 1 second , lung diffusing capacity for carbon monoxide , histology , and clinical T and N status . Medical records were review ed and survival was analyzed . RESULTS After matching , there were 208 patients in each group . Patient and tumor characteristics were similar . The VATS group had a shorter length of stay . More nodes ( 14.3 versus 11.3 ; p=0.001 ) and more nodal stations ( 3.8 versus 3.1 ; p<0.001 ) were removed by thoracotomy . No differences were seen in OS and DFS . Median follow-up was 36 months . More than 90 % of patients had clinical stage I disease , with 3- and 5-year OS of 87.4 % and 76.5 % , respectively , for VATS , and 81.6 % and 77.5 % , respectively , for thoracotomy ( p=0.672 ) . Both the incidence and distribution of recurrence were similar . Multivariate Cox regression analyses of OS and DFS confirmed the noninferiority of VATS . CONCLUSIONS For patients with clinical stage I NSCLC , VATS lobectomy offered similar OS and DFS compared with thoracotomy . Thoracotomy offers a more thorough lymph node evaluation , and may be appropriate for patients with more advanced clinical disease The European Society of Thoracic Surgeons ( ESTS ) organized a workshop dealing with lymph node staging in non-small cell lung cancer . The objective of this workshop was to develop guidelines for definitions and the surgical procedures of intraoperative lymph node staging , and the pathologic evaluation of resected lymph nodes in patients with non-small cell lung cancer ( NSCLC ) . Relevant peer- review ed publications on the subjects , the experience of the participants , and the opinion of the ESTS members contributing on line , were used to reach a consensus . Systematic nodal dissection is recommended in all cases to ensure complete resection . Lobe-specific systematic nodal dissection is acceptable for peripheral squamous T1 tumors , if hilar and interlobar nodes are negative on frozen section studies ; it implies removal of , at least , three hilar and interlobar nodes and three mediastinal nodes from three stations in which the subcarinal is always included . Selected lymph node 
    Output:
    
Conclusions Open lobectomy could achieve better LN dissection efficacy than thoracoscopic lobectomy in the treatment of lung cancer , especially in the N2 LNs dissection .