***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: AIM To assess the feasibility and efficacy of laparoscopic total mesorectal excision ( LTME ) of low rectal cancer with preservation of anal sphincter . METHODS From June 2001 to June 2003 , 82 patients with low rectal cancer underwent laparoscopic total mesorectal excision with preservation of anal sphincter . The lowest edge of tumors was below peritoneal reflection and 1.5 - 7 cm from the dentate line ( 1.5 - 5 cm in 48 cases , 5 - 7 cm in 34 cases ) . RESULTS LTME with anal sphincter preservation was performed on 82 r and omized patients with low rectal cancer , and 100 % sphincter preservation rate was achieved . There were 30 patients with laparoscopic low anterior resection ( LLAR ) at the level of the anastomosis below peritoneal reflection and 2 cm above from the dentate line ; 27 patients with laparoscopic ultralow anterior resection ( LULAR ) at the level of anastomoses 2 cm below from the dentate line ; and 25 patients with laparoscopic coloanal anastomoses ( LCAA ) at the level of the anastomoses at or below the dentate line . No defunctioning ileostomy was created in any case . The mean operating time was 120 minutes ( ranged from 110 - 220 min ) , and the mean operative blood loss was 20 mL ( ranged from 5 - 120 mL ) . Bowel function was restored and diet was resumed on day 1 or 2 after operation . The mean hospital stay was 8 days ( ranged from 5 - 14 ) . Postoperative analgesics were used in 45 patients . After surgery , 2 patients had urinary retention , one had anastomotic leakage , and another 2 patients had local recurrence one year later . No interoperative complication was observed . CONCLUSION LTME with preservation of anal sphincter is a feasible , safe and minimally invasive technique with less postoperative pain and rapid recovery , and importantly , it has preserved the function of the sphincter Background The role of laparoscopic resection ( LR ) in the management of extraperitoneal rectal cancer still is unclear . This study aim ed to compare perioperative and long-term results of laparoscopic and open resection ( OR ) for low and midrectal cancer . Methods A prospect i ve nonr and omized trial comparing patients su bmi tted to OR or LR for low and midrectal cancer at a single institution was conducted . Results The study included 191 consecutive patients : 98 patients who underwent LR and 93 who underwent OR .  The mean follow-up period was 46.3 months for LR and 49.7 months for OR . The conversion rate for LR was 18.4 % . With the use of LR , the mean time for complete patient mobilization was shorter ( 1.7 vs 3.3 days ; p < 0.001 ) and patients were earlier in passing flatus ( 2.6 vs 3.9 days ; p < 0.001 ) and stools ( 3.8 vs 4.7 days ; p < 0.01 ) , and in resuming oral intake ( 3.4 vs 4.8 days ; p < 0.001 ) . The mean hospital stay was shorter for LR , but the difference did not reach significance ( 11.4 vs 13 days ) . Morbidity and mortality rates were similar : LR ( 24.4 % and 1 % ) and OR ( 23.6 % and 2.2 % ) . Laparoscopic patients presented a higher rate of anastomotic fistulas ( 13.5 % vs 5.1 % ) and reoperations ( 6.1 % vs 3.2 % ) but the difference was statistically nonsignificant . Laparoscopic resection presented a significantly lower local recurrence rate ( 3.2 % vs 12.6 % ; p < 0.05 ) . The cumulative survival and disease-free rates at 5 years were , respectively , 80 % and 65.4 % after LR and 68.9 % and 58.9 % after OR ( nonsignificant difference ) . Stage-by-stage comparison showed prolonged cumulative survival for stages III and IV cancer in LR ( 82.5 % vs 40.5 % ; p = 0.006 and 15.8 % vs 0 % ; p = 0.013 , respectively ) and a reduced rate of cancer-related death for stage III in LR ( 11.4 % vs 51.9 % ; p = 0.001 ) . Conclusions As compared with conventional open surgery , LR for low and midrectal cancer is characterized by a faster recovery and similar overall morbidity ( but a higher rate of anastomotic leakages ) , and does not present any adverse oncologic effect Objective To assess the efficacy of a novel coloplasty colonic pouch design in optimizing bowel function after ultralow anterior resection . Summary Background Data A colonic J-pouch may reduce excessive stool frequency and incontinence after anterior resection , but at the risk of evacuation problems . Experimental surgery on pigs has suggested that a coloplasty pouch ( CP ) may be a useful alternative . Although CP has recently been shown to be feasible in patients , there is no r and omized controlled trial comparing bowel function with the J-pouch . Methods After anterior resection for cancer , patients were allocated to either  J-pouch or CP-anal anastomoses .  Continence scoring , anorectal manometry , and endoanal ultrasound assessment s were made before surgery . All complications were recorded , and these preoperative assessment s were repeated at 4 months . The assessment s were repeated again at 1 year , and a quality of life question naire was added . Results Eighty-eight patients were recruited from October 1998 to April 2000 . Both groups were well matched for age , gender , staging , adjuvant therapy , and mean follow-up . There were no differences in the intraoperative time and hospital stay . CP result ed in more anastomotic leaks . At 4 months , J-pouch patients had 10.3 % less stool fragmentation but poorer stool deferment and more nocturnal leakage . However , there were no differences in the bowel function , continence score , and quality of life at 1 year . There were no differences in the anorectal manometry and endoanal ultrasound findings . Conclusions Coloplasty pouches result ed in more anastomotic leaks and minimal differences in bowel function . At present , the J-pouch remains the benchmark for routine clinical practice , and due care ( including defunctioning stoma ) should be exercised in situations requiring CP Objectives To compare a colonic J-pouch or a side-to-end anastomosis after low-anterior resection for rectal cancer with regard to functional and surgical outcome . Summary Background Data A complication after restorative rectal surgery with a straight anastomosis is low-anterior resection syndrome with a postoperatively deteriorated anorectal function . The colonic J-reservoir is sometimes used with the purpose of reducing these symptoms . An alternative method is to use a simple side-to-end anastomosis . Methods One-hundred patients with rectal cancer undergoing total mesorectal excision and colo-anal anastomosis were r and omized  to receive either a colonic pouch or a side-to-end anastomosis using the descending colon . Surgical results and complications were recorded . Patients were followed with a functional evaluation at 6 and 12 months postoperatively . Results Fifty patients were r and omized to each group . Patient characteristics in both groups were very similar regarding age , gender , tumor level , and Dukes ’ stages . A large proportion of the patients received short-term preoperative radiotherapy ( 78 % ) . There was no significant difference in surgical outcome between the 2 techniques with respect to anastomotic height ( 4 cm ) , perioperative blood loss ( 500 ml ) , hospital stay ( 11 days ) , postoperative complications , reoperations or pelvic sepsis rates . Comparing functional results in the 2 study groups , only the ability to evacuate the bowel in < 15 minutes at 6 months reached a significant difference in favor of the pouch procedure . Conclusions The data from this study show that either a colonic J-pouch or a side-to-end anastomosis performed on the descending colon in low-anterior resection with total mesorectal excision are methods that can be used with similar expected functional and surgical results PURPOSE The optimal timing of surgery after preoperative radiotherapy in rectal cancer is unknown . The aim of this trial was to evaluate the role of the interval between preoperative radiotherapy and surgery . PATIENTS AND METHODS Patients with rectal carcinoma accessible to rectal digital examination , staged T2 to T3 , NX , M0 , were r and omized before radiotherapy ( 39 Gy in 13 fractions ) into two groups : in the short interval ( SI ) group , surgery had to be performed within 2 weeks after completion of radiation therapy , compared with 6 to 8 weeks in the long interval ( LI ) group . Between 1991 and 1995 , 201 patients were enrolled onto the study . RESULTS A long interval between preoperative radiotherapy and surgery was associated with a significantly better clinical tumor response ( 53 . 1 % in the SI group v 71.7 % in the LI group , P = .007 ) and pathologic downstaging ( 10.3 % in the SI group v 26 % in the LI group , P = .005 ) . At a median follow-up of 33 months , there were no differences in morbidity , local relapse , and short-term survival between the two groups . Sphincter-preserving surgery was performed in 76 % of cases in the LI group versus 68 % in the SI group ( P = 0.27 ) . CONCLUSION A long interval between preoperative irradiation and surgery provides increased tumor downstaging with no detrimental effect on toxicity and early clinical results . When sphincter preservation is question able , a long interval may increase the chance of a successful sphincter-saving surgery Mesorectal excision for rectal cancer has result ed in local recurrence rates of 3–11 per cent compared with up to 38 per cent after conventional methods . The results of a prospect i ve Danish study with a historical control group are presented Abstract . Although increasing evidence suggests that prophylactic drainage after intra-peritoneal colorectal anastomoses is unnecessary , drains for infra-peritoneal rectal anastomoses , where the leak rate is higher , are widely employed still . The aim of this study was to assess the effect of prophylactic drainage after anastomosis below the peritoneal reflection . All patients attending one specialist unit over an 8-month period for elective rectal cancer resection with an infra-peritoneal anastomosis were r and omised to drainage or no drainage . The incidence of anastomotic leak and complications specific to the drain as well as other complications were compared . Fifty-nine patients were analysed ( 31 with drain ) . Twenty-five of the drained and 16 of the no-drain patients had a defunctioning stoma ( p = ns ) . The groups were comparable for demographic data , operation and anastomotic height from the anal verge . There were three leaks ( 10 % ) in the drain group and five leaks ( 18 % ) in the no-drain group ( p = ns ) . There were 2 ( 7 % ) patients in each group with a clinical leak . There were no specific drain complications and the incidence of other complications was similar in both groups . In conclusion , this study supports the contention that there is no difference in morbidity with or without the use of a drain for infra-peritoneal anastomoses Abstract Background : A population based prospect i ve r and omized trial on preoperative radiotherapy in operable rectal cancer was conducted in Stockholm , Sweden . Five hundred fifty-seven patients from 12 institutions were included with histologically proven , clinical ly resectable rectal adenocarcinoma . Patients planned for local excision or previously irradiated to the pelvis were excluded . Methods : A total of 272 patients were allocated to preoperative irradiation with 25 Gy in five cycles during 5–7 days to the rectum and the pararectal tissues ( RT+ group ) and 285 patients were allocated to surgery only ( RT− group ) . The median follow-up time was 50 months . No patient was lost to follow-up . Surgery was considered curative in 479 patients ( 86 % ) . Results : Locoregional recurrence occurred in 10 % of the patients in the RT+ group versus 21 % in the RT− group ( p<0.01 ) . Among the curatively operated patients , distant metastases occurred in 19 % in the RT+ group versus 26 % in the RT− group ( p=0.02 ) . The overall survival was improved in the irradiated patients ( p=0.02 ) . Postoperative complications were more common after irradiation but were usually mild . The postoperative mortality was low in both groups . Conclusion : Preoperative short-term , high-dose radiotherapy as given in this trial reduces the risk of local and distant recurrence and improves survival after curative surgery for rectal carcinoma PURPOSE : The aim of this study was to investigate the role of omentoplasty , by means of intact omentum , in preventing anastomotic leakages after rectal resection . METHODS : Between 1992 and 1997 a total of 112 patients ( 64 males ) with a mean age of 64.7 ( range , 39–83 ) years were r and omly assigned to undergo omentoplasty ( Group A ) or not ( Group B ) 
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Year of publication , use of preoperative radiation , use of laparoscopy , and use of protecting stoma were not significant variables , but average age , median tumor height , and method of detection ( clinical vs. radiologic ) showed significance to explain heterogeneity in anastomotic leak rates .
Year of publication , study origin , average age , and use of laparoscopy were significant , but median tumor height and preoperative radiation use were not significant in explaining heterogeneity among observed postoperative death rates .
With multivariable analysis , only average age for anastomotic leak and year of publication for postoperative death remained significant .
Benchmark complication rates for radical rectal cancer surgery were obtained for use in sample size calculations in future studies and for quality control purpose s. Postoperative death rates showed improvement in recent years