***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVE To determine the safety of laparoscopy-assisted distal gastrectomy ( LADG ) compared with open distal gastrectomy ( ODG ) in patients with clinical stage I gastric cancer in Korea . BACKGROUND There is still a lack of large-scale , multicenter r and omized trials regarding the safety of LADG . METHODS A large-scale , phase 3 , multicenter , prospect i ve r and omized controlled trial was conducted . The primary end point was 5-year overall survival . Morbidity within 30 postoperative days and surgical mortality were compared to evaluate the safety of LADG as a secondary end point RESULTS : A total of 1416 patients were r and omly assigned to the LADG group ( n = 705 ) or the ODG group ( n = 711 ) between February 1 , 2006 , and August 31 , 2010 , and 1384 patients were analyzed for modified intention-to-treat analysis ( ITT ) and 1256 were eligible for per protocol ( PP ) analysis ( 644 and 612 , respectively ) . In the PP analysis , 6 patients ( 0.9 % ) needed open conversion in the LADG group . The overall complication rate was significantly lower in the LADG group ( LADG vs ODG ; 13.0 % vs 19.9 % , P = 0.001 ) . In detail , the wound complication rate of the LADG group was significantly lower than that of the ODG group ( 3.1 % vs 7.7 % , P < 0.001 ) . The major intra-abdominal complication ( 7.6 % vs 10.3 % , P = 0.095 ) and mortality rates ( 0.6 % vs 0.3 % , P = 0.687 ) were similar between the 2 groups . Modified ITT analysis showed similar results with PP analysis . CONCLUSIONS LADG for patients with clinical stage I gastric cancer is safe and has a benefit of lower occurrence of wound complication compared with conventional ODG BACKGROUND Laparoscopic surgery as an alternative to open surgery in patients with rectal cancer has not yet been shown to be oncologically safe . The aim in the COlorectal cancer Laparoscopic or Open Resection ( COLOR II ) trial was to compare laparoscopic and open surgery in patients with rectal cancer . METHODS A non-inferiority phase 3 trial was undertaken at 30 centres and hospitals in eight countries . Patients ( aged ≥18 years ) with rectal cancer within 15 cm from the anal verge without evidence of distant metastases were r and omly assigned to either laparoscopic or open surgery in a 2:1 ratio , stratified by centre , location of tumour , and preoperative radiotherapy . The study was not masked . Secondary ( short-term ) outcomes -including operative findings , complications , mortality , and results at pathological examination-are reported here . Analysis was by modified intention to treat , excluding those patients with post-r and omisation exclusion criteria and for whom data were not available . This study is registered with Clinical Trials.gov , number NCT00297791 . FINDINGS The study was undertaken between Jan 20 , 2004 , and May 4 , 2010 . 1103 patients were r and omly assigned to the laparoscopic ( n=739 ) and open surgery groups ( n=364 ) , and 1044 were eligible for analyses ( 699 and 345 , respectively ) . Patients in the laparoscopic surgery group lost less blood than did those in the open surgery group ( median 200 mL [ IQR 100 - 400 ] vs 400 mL [ 200 - 700 ] , p<0·0001 ) ; however , laparoscopic procedures took longer ( 240 min [ 184 - 300 ] vs 188 min [ 150 - 240 ] ; p<0·0001 ) . In the laparoscopic surgery group , bowel function returned sooner ( 2·0 days [ 1·0 - 3·0 ] vs 3·0 days [ 2·0 - 4·0 ] ; p<0·0001 ) and hospital stay was shorter ( 8·0 days [ 6·0 - 13·0 ] vs 9·0 days [ 7·0 - 14·0 ] ; p=0·036 ) . Macroscopically , completeness of the resection was not different between groups ( 589 [ 88 % ] of 666 vs 303 [ 92 % ] of 331 ; p=0·250 ) . Positive circumferential resection margin ( < 2 mm ) was noted in 56 ( 10 % ) of 588 patients in the laparoscopic surgery group and 30 ( 10 % ) of 300 in the open surgery group ( p=0·850 ) . Median tumour distance to distal resection margin did not differ significantly between the groups ( 3·0 cm [ IQR 2·0 - 4·8 ] vs 3·0 cm [ 1·8 - 5·0 ] , respectively ; p=0·676 ) . In the laparoscopic and open surgery  groups , morbidity ( 278 [ 40 % ] of 697 vs 128 [ 37 % ] of 345 , respectively ; p=0·424 ) and mortality ( eight [ 1 % ] of 699 vs six [ 2 % ] of 345 , respectively ; p=0·409 ) within 28 days after surgery were similar . INTERPRETATION In selected patients with rectal cancer treated by skilled surgeons , laparoscopic surgery result ed in similar safety , resection margins , and completeness of resection to that of open surgery , and recovery was improved after laparoscopic surgery . Results for the primary endpoint-locoregional recurrence-are expected by the end of 2013 . FUNDING Ethicon Endo-Surgery Europe , Swedish Cancer Foundation , West Gothia Region , Sahlgrenska University Hospital Background The purpose of this study is to compare and evaluate the security and efficacy of 3D vs 2D laparoscopy in rectal cancer treatment . Methods Forty-six patients who suffered from rectal cancer and went on laparoscopic radical resection of rectal carcinoma in Peking University Shougang Hospital from Feb. 2015 to Mar. 2016 were included in the study . They were r and omly divided into two groups . The 23 patients operated with the 3D system were compared with 23 patients operated with the 2D system by perioperative data . Results There were no significant differences in age , sex , pathological type , tumor differentiation , TNM staging , and surgical procedures ( P > 0.05 ) . The average operating time of 3D laparoscopic surgery group ( 172.2 ± 27.5 min ) was shorter than that of 2D group ( 192.6 ± 22.3 ) ( P < 0.05 ) ; the rate of transfer to laparotomy is lower in 2D group ( 72.7 % ) than in 3D group ( 86.4 % ) , but they have no significant difference ; and the intraoperative blood loss ( 247.0 ± 173.6 ml vs 282.6 ± 195.6 ml ) , postoperative passage of flatus ( 2.8 ± 0.8 days vs 3.1 ± 1.0 days ) , and indwelling catheter time ( 5.6 ± 1.9 days vs 6.3 ± 2.0 days ) in 3D group and 2D group ( P > 0.05 ) were not significantly different . There were no differences in other complications between the two groups . No significantly different recrudescence and death rates were found between the two groups ( P > 0.05 ) . Conclusion The 3D laparoscopy shortens the operation time of rectum cancer . 3D laparoscopic surgery is more efficient in treatment of rectal cancer than 2D laparoscopy and is worth of being generalized Non-r and omised studies of the effects of interventions are critical to many areas of healthcare evaluation , but their results may be biased . It is therefore important to underst and and appraise their strengths and weaknesses . We developed ROBINS-I ( “ Risk Of Bias In Non-r and omised Studies - of Interventions ” ) , a new tool for evaluating risk of bias in estimates of the comparative effectiveness ( harm or benefit ) of interventions from studies that did not use r and omisation  to allocate units ( individuals or clusters of individuals ) to comparison groups . The tool will be particularly useful to those undertaking systematic review s that include non-r and omised studies BACKGROUND Several three-dimensional video-endoscopic systems have been introduced to enhance depth perception during minimum-access surgery . However , there is no conclusive evidence of benefit , and these systems are more expensive than conventional two-dimensional systems . We undertook a prospect i ve r and omised comparison of two-dimensional and three-dimensional imaging in elective laparoscopic cholecystectomy for symptomatic gallstone disease . METHODS The operations were done by four specialist registrars as part of their higher surgical training . 60 operations were r and omised for execution by either two-dimensional or three-dimensional imaging display ( 30 by each method ) . The degree of difficulty of the operation was grade d by a consultant surgeon on a st and ard grading system . The primary endpoints were execution time and the errors made during the procedure . The secondary endpoints were subjective assessment of the image quality and adverse effects on the surgeon . FINDINGS There was no difference between the two-dimensional and three-dimensional display groups in median execution time ( 3160 [ IQR 2735 - 4335 vs 3100 [ 2379 - 3710 ] s ; p = 0.2 ) or error rate ( six vs six ) . Surgeons reported adverse symptoms immediately after the operations with both systems . The scores for visual strain , headache , and facial discomfort were higher with the three-dimensional system . INTERPRETATION With the current technology , three-dimensional systems based on sequential imaging show no advantage over two-dimensional systems in the conduct of laparoscopic cholecystectomy Objective To determine the relative safety and efficacy of 3D laparoscopic gastrectomy and 2D laparoscopic surgery in patients with gastric cancer . Background There is still a lack of r and omized controlled trials regarding the safety and efficacy of 3D versus 2D laparoscopic surgery for gastric cancer . Methods A large‐scale , phase 3 , prospect i ve , r and omized controlled trial was conducted . ( Clinical Trials.gov number NCT02327481 ) . Results A total of 438 patients were r and omized ( 3D group : 219 cases ; 2D group : 219 cases ) between January 1 , 2015 , and April 1 , 2016 ; 19 patients were excluded . Finally , data from 419 patients were analyzed ( 3D group : 211 cases ; 2D group : 208 cases ) . There were no differences between the 2 groups regarding the operation time ( 3D versus 2D , 176 ± 35 min vs. 174 ± 33 min , P = .562 ) . The intraoperative blood loss in the 3D group was somewhat less than in the 2D group ( 61 ± 83 mL vs. 82 ± 119 mL , P = .045 ) . Further analysis suggested that the use of 3D laparoscopic surgery was a protective factor against excessive blood loss ( ≥200 mL ) . Conclusion 3D laparoscopic gastrectomy did not shorten the operation time compared with 2D laparoscopic gastrectomy , but provided the benefit of less intraoperative blood loss and a lesser occurrence of excessive bleeding  than the conventional 2D laparoscopic gastrectomy ; the clinical value of the difference is limited Purpose 3D imaging is an upcoming technology in laparoscopic surgery , and recent studies have shown that the modern 3D technique is superior in an experimental setting . Methods All 14 members of the Asklepios Klinik Langen Department of Visceral and Thoracic Surgery , as well as two gynaecologists , were asked to undertake 2D vs. 3D laparoscopic black box skill training . The black box training was adapted to the “ fundamentals of laparoscopic surgery ” programme provided by the Society of American Gastrointestinal and Endoscopic Surgeons ( SAGES ) . First , the participants categorised themselves as beginner , advanced or expert in laparoscopic surgery . Then , they were r and omised in terms of whether the black box training commenced with 2D or 3D vision . The exercises included peg transfer with the dominant h and and the non-dominant h and ( with and without transfer between the graspers ) , needle capping and cutting a sutured knot . The time taken to complete these exercises was measured . After the training , each participant was asked to describe his/her personal impression of the imaging systems employed . Results Overall , for the participants in all groups , the time required for all exercises showed a significant advantage for 3D imaging ( 3D vs. 2D ; Wilcoxon matched pair test ; mean 68.0 ± 94.9 s ( 3D ) vs. 90.1 ± 69.4 s ( 2D ) ; p = 0.002 ) . Regarding the subgroups , the experts significantly improved their time in completing the exercises in 3D vs. 2 
    Output:
    
Main advantages of 3D laparoscopic gastrectomy for gastric cancer were that it could shorten the operation time and reduce the amount of intraoperative blood loss .
However , 3D laparoscopic surgery had no obvious advantage over 2D laparoscopic surgery for colorectal cancer patients