***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: AIMS The st and ard surgical procedure for elderly ( ≥ 70 years ) patients with clinical stage I non-small cell lung cancer ( NSCLC ) was investigated . METHODS A non-r and omized prospect i ve controlled study was conducted to compare lobectomy with segmental resection for the treatment of elderly clinical stage I lung cancer patients under different pulmonary function . Perioperative indicators including time and volume of thoracic drainage , incidence of postoperative complications , locoregional recurrence rates , and 1 , 3 , and 5-year survival rates were analyzed . RESULTS A total of 184 patients were included in the study . Patients were classified into two groups according to pulmonary function : group 1 included 64 patients who had poor pulmonary function , with a forced expiratory volume in 1 s ( FEV(1 ) ) of less than 1.5 L , whereas group 2 consisted of 120 patients with an FEV(1 ) ≥ 1.5 L. The patients in group 1 had a longer postoperative mechanical ventilation time and a higher incidence rate of respiratory associated complications than those in group 2 ( 21.9 vs. 8.35 % , p = 0.009 ) . The local recurrence and long-term survival rates were not significantly different between lobectomy and segmental resection . Among the patients who underwent segmental resection , those who had regional lymph node dissection showed a higher 3-year and 5-year survival rate than those undergoing selected lymph node resection ( 77.8 vs. 51.7 % , p = 0.042 ; 55.6 vs. 27.6 % , p = 0.034 ) , but this was not significant in lobectomy . CONCLUSIONS Segmental resection combined with regional lymph node resection could be the best choice for elderly clinical stage I NSCLC patients with FEV(1 ) < 1.5 OBJECTIVES To comparatively evaluate lobectomy and limited resection for T1 N0 M0 non-small-cell lung cancer , we review ed case series with concurrent nonr and omized controls . METHODS Limited resection with curative intent was performed for 63 patients with T1 N0 M0 non-small-cell lung cancer over a 10-year period . These 63 patients included 46 patients who underwent a segmentectomy as an intentional limited resection .  These patients had good pulmonary function and could tolerate a lobectomy in the management of their disease . The other 17 patients underwent wedge resection or segmentectomy as a compromised limited resection because they had poor pulmonary reserve or other limiting factors and could withst and a thoracotomy but could not tolerate a lobectomy in the management of their disease . RESULTS The 5-year survival was 93 % in the intentional resection group . The survival curve for this group was not different from that for 77 patients who underwent the st and ard operation ( lobectomy plus complete mediastinal lymph node dissection ) for T1 N0 M0 non-small-cell lung cancer during the same period . The frequency of local/regional recurrence in the intentional resection group was 8.7 % ( 4/46 ) ; the recurrence in three patients was situated in the mediastinum . According to multivariate analysis , limited resection was not associated with poor survival . CONCLUSION Segmentectomy with regional lymph node dissection , including the mediastinum , should be considered as an acceptable alternative treatment for selected patients with T1 N0 M0 disease Background The results of R and omized Controlled Trials ( RCTs ) on time-to-event outcomes that are usually reported are median time to events and Cox Hazard Ratio . These do not constitute the sufficient statistics required for meta- analysis or cost-effectiveness analysis , and their use in secondary analyses requires strong assumptions that may not have been adequately tested . In order to enhance the quality of secondary data analyses , we propose a method which derives from the published Kaplan Meier survival curves a close approximation to the original individual patient time-to-event data from which they were generated . Methods We develop an algorithm that maps from digitised curves back to KM data by finding numerical solutions to the inverted KM equations , using where available information on number of events and numbers at risk . The reproducibility and accuracy of survival probabilities , median survival times and hazard ratios based on reconstructed KM data was assessed by comparing published statistics ( survival probabilities , medians and hazard ratios ) with statistics based on repeated reconstructions by multiple observers . Results The validation exercise established there was no material systematic error and that there was a high degree of reproducibility for all statistics . Accuracy was excellent for survival probabilities and medians , for hazard ratios reasonable accuracy can only be obtained if at least numbers at risk or total number of events are reported . Conclusion The algorithm is a reliable tool for meta- analysis and cost-effectiveness analyses of RCTs reporting time-to-event data . It is recommended that all RCTs should report information on numbers at risk and total number of events alongside KM curves BACKGROUND It has been reported that limited resection ( segment or wedge ) is equivalent to lobectomy in the management of early stage ( T1 - 2 N0 ) non-small cell lung cancer . METHODS A prospect i ve , multiinstitutional r and omized trial was instituted comparing limited resection with lobectomy for patients with peripheral T1 N0 non-small cell lung cancer documented at operation . Analysis included locoregional and distant recurrence rates , 5-year survival rates , perioperative morbidity and mortality , and late pulmonary function assessment . RESULTS There were 276 patients r and omized , with 247 patients eligible for analysis . There were no significant differences for all stratification variables , selected prognostic factors , perioperative morbidity , mortality , or late pulmonary function . In patients undergoing limited resection , there was an observed 75 % increase in recurrence rates ( p = 0.02 , one-sided ) attributable to an observed tripling of the local recurrence rate ( p = 0.008 two-sided ) , an observed 30 % increase in overall death rate ( p = 0.08 , one-sided ) , and an observed 50 % increase in death with cancer rate ( p = 0.09 , one-sided ) compared to patients undergoing lobectomy ( p = 0.10 , one-sided was the predefined threshold for statistical significance for this equivalency study ) . CONCLUSIONS Compared with lobectomy , limited pulmonary resection does not confer improved perioperative morbidity , mortality , or late postoperative pulmonary function . Because of the higher death rate and locoregional recurrence rate associated with limited resection , lobectomy still must be considered the surgical procedure of choice for patients with peripheral T1 N0 non-small cell lung cancer BACKGROUND Lesser resection than the st and ard lobectomy for small-sized cT1N0M0 non-small cell lung cancers continues to be debated . METHODS We review ed specimens of 139 patients after lobectomy for cT1N0M0 cancer of 2 cm or less . In addition , we prospect ively enrolled 70 patients able to tolerate a lobectomy , in a trial of lesser resection for these lesions . The limited procedure consisted of segmentectomy in which the resection line was delivered beyond the burdened segment , plus exploration of lymph nodes by frozen sectioning . This procedure was modified if the result was positive ; this modified procedure was called extended segmentectomy . RESULTS The nodal status after lobectomy was pN0 , 107 patients ; pN1 , 12 patients ; and pN2 , 20 patients . Of the pN1 patients , 2 had only intralobar nodal involvement within the same segment of the main tumor . In the remaining 30 patients with nodal involvement , we ascertained the nodal involvement during the operation . Regarding intrapulmonary metastasis , 1 of 8 patients having this metastasis had the lesion at the segment where the main tumor was not located and had N2 disease , which was detected intraoperatively . If extended segmentectomy had been performed instead of lobectomy , the lesion could have been removed completely . The 5-year survival of patients with cT1N0M0 cancer of 2 cm or less was 87.3 % after extended segmentectomy . There were no local recurrences and three noncancer-related deaths . Among patients with pT1N0M0 cancer of 2 cm or less , the 5-year survival was 87.1 % in the extended segmentectomy group and 87.7 % in the lobectomy group ( p = 0.8008 ) . CONCLUSIONS Extended segmentectomy should be considered as an alternative for patients with cT1N0M0 non-small cell lung cancer of 2 cm or smaller OBJECTIVE The aim of this study was to assess the adequacy of our intentional limited resection for small peripheral lung cancer based on intraoperative pathologic exploration . METHODS Patients who had stage IA non-small cell lung cancer ( NSCLC ) with a maximum tumor diameter of 2 cm or less were c and i date s for limited resection .  If bronchioloalveolar carcinoma ( BAC ) was suspected on computed tomography and intraoperative pathologic exploration revealed the lesion as BAC without foci of active fibroblastic proliferation ( Noguchi type A and B ) , wedge resection was performed . If the tumor was not suspected of being Noguchi type A or B , extended segmentectomy with intraoperative lymph node exploration was performed . RESULTS Limited resection was performed in 34 patients , wedge resection in 14 , and extended segmentectomy in 20 . The median follow-up period after wedge resection was 36 months , and all patients are alive with no signs of recurrence . The median follow-up period after extended segmentectomy was 54 months . No local recurrences were found , but distant metastasis was diagnosed in one patient . The 5-year survival rate after extended segmentectomy was 93 % . In the same period , lobectomy was performed in 57 patients with stage IA NSCLC with a maximum tumor diameter of 2 cm or less , and the 5-year survival rate was 84 % . There were no significant differences in 5-year survival between extended segmentectomy and lobectomy . CONCLUSIONS Careful selection of patients based on high-resolution computed tomography findings and intraoperative pathologic exploration makes intentional limited resection an acceptable option for the treatment of small peripheral NSCLC PURPOSE Although anatomic segmentectomy has been considered a compromised procedure by many surgeons , recent retrospective , single-institution series have demonstrated tumor recurrence and patient survival rates that approximate those achieved by lobectomy . The primary objective of this study was to use propensity score matching to compare outcomes after these anatomic resection approaches for stage I non-small-cell lung cancer . PATIENTS AND METHODS A retrospective data set including 392 segmentectomy patients and 800 lobectomy patients was used to identify matched segmentectomy and lobectomy cohorts ( n = 312 patients per group ) using a propensity score matching algorithm that accounted for confounding effects of preoperative patient variables . Primary outcome variables included freedom from recurrence and overall survival . Factors affecting survival were assessed by Cox regression analysis and Kaplan-Meier estimates . RESULTS Perioperative mortality was 1.2 % in the segmentectomy group and 2.5 % in the lobectomy group ( P = .38 ) . At a mean follow-up of 5.4 years , comparing segmentectomy with lobectomy , no differences were noted in locoregional ( 5.5 % v 5.1 % , respectively ; P = 1.00 ) , distant ( 14.8 % v 11.6 % , respectively ; P = .29 ) , or overall recurrence rates ( 20.2 % v 16.7 % , respectively ; P = .30 ) . Furthermore , when comparing segmentectomy with lobectomy , no significant differences were noted in 5-year freedom from recurrence ( 70 % v 71 % , respectively ; P = .467 ) or 5-year survival ( 54 % v 60 % , respectively ; P = .258 ) . Segmentectomy was not found to be an independent predictor of recurrence ( hazard ratio , 1.11 ; 95 % CI , 0.87 to 1.40 ) or overall survival ( hazard ratio , 1.17 ; 95 % CI , 0.89 to 1.52 ) . CONCLUSION In this large propensity-matched comparison , lobectomy was associated with modestly increased freedom from recurrence and overall survival , but the differences were not statistically significant . These results will need further validation by prospect i ve , r and omized trials ( eg , Cancer and Leukemia Group B 140503 trial ) OBJECTIVE The present intervention study was conducted to prospect ively evaluate the long-term prognosis for video-assisted limited surgery , such as wedge resection and segmentectomy , for clinical ly early lung cancers depending on findings in high-resolution computed tomography ( H RCT ) . SUBJECTS AND METHODS Patients were enrolled in the study between 2001 and 2004 , and followed up for five subsequent years . Of these patients , those with a clinical stage IA lung cancer mainly comprising a ground glass-opacity ( GGO ) less than 1.5 cm across underwent thoracoscopic wedge resection of the lung ( Group A ) . Patients with a tumour less than 2.0 cm in diameter , not classified in Group A , underwent video-assisted segmentectomy and hilar lymph node dissection with lobe-specific mediastinal nodes sampling ( Group B ) . For patients with a tumour less than 3.0 cm in diameter , not classified in to any of the foregoing two groups , underwent video-assisted lobectomy and hilar and mediastinal lymph node dissection 
    Output:
    
The survival in the segmentectomy group was not inferior to patients treated with lobectomy .
In conclusion , the current meta- analysis disclosed that segmentectomies produce similar survival compared to lobectomy for patients with stage I NSCLC .