human
***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: 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 A series of 103 consecutive rectal cancers was prospect ively documented . Laparotomy was performed in 78 patients of whom five did not undergo resection . Resection was considered curative unless there were liver metastases or biopsy‐proven residual disease . Nine patients had a palliative resection . Thus 64 patients underwent a curative resection , 52 ( 81 per cent ) of whom had an anterior resection of which 26 ( 46 per cent ) were performed by trainees . There were three deaths after operation . Eight ( 14 per cent ) patients developed a clinical anastomotic leak . Thirty patients were available for a minimum follow‐up of 24 ( mean 33 , range 24–49 ) months . Four ( 13 per cent ) patients developed distant recurrence . There were no isolated pelvic or anastomotic recurrences . One patient with distal recurrence may have had pelvic disease . The cumulative recurrence – free survival rate at 24 months was 84 per cent . These results support the suggestion that mesorectal excision may reduce local recurrence Adjuvant preoperative radiotherapy of patients with primary rectal carcinoma improves local control and survival , but also may increase the risk of early postoperative morbidity and mortality . In addition , the possible late adverse effects of this treatment are largely unknown From 1980 to 1985 , 471 patients with resectable rectal and rectosigmoid cancer were r and omly allocated to receive either preoperative short-term high-dose irradiation ( 25.5 Gy in one week ) for all patients or prolonged postoperative radiotherapy ( 60 Gy in seven to eight weeks ) only for patients with a Dukes B or C lesion . After a minimum follow-up of five years , the local recurrence rate was statistically significantly lower after preoperative than after postoperative radiotherapy ( 13 percentvs.22 percent;P=0.02 ) . No difference in overall survival was noted ( P=0.5 ) . To evaluate possible late side effects on the bowel , urinary bladder , or skin after surgery and additional preoperative or postoperative radiotherapy , all patients included in the r and omized trial , together with 58 patients from a preceding pilot study with the same preoperative regimen , were studied in a prolonged follow-up program . The hospital files of all patients were re-examined . Of the patients who were carefully examined , 176 had a survival exceeding five years and 19 had a survival exceeding 10 years . Overall , 7 percent ( 33/ 464 ) either were operated upon or have had a radiologic diagnosis of small bowel obstruction : 14/255 ( 5 percent ) after preoperative irradiation , 14/127 ( 11 percent ) after postoperative irradiation , and 5/82 ( 6 percent ) after surgery alone . The cumulative risk of developing a bowel obstruction was significantly increased after postoperative radiotherapy . Among the 98 patients alive after preoperative irradiation , significant morbidity from the bowel was noted in 11 patients , from the urinary bladder in two , and from the skin in six . In the postoperatively treated group of 34 patients , the bowel , urinary bladder , and skin morbidity were significant in five , two , and five patients , respectively . Corresponding morbidity in 44 nonirradiated patients was seen in five , one , and two patients , respectively . It is concluded that preoperative , short-term , high-dose radiotherapy decreases the local recurrence rate relative to postoperative radiotherapy , with no indications of increased late morbidity after a follow-up of 5 to 10 years The authors have studied the value of preoperative radiotherapy in 125 patients with cancer of the rectum . The patients were divided into two groups , control ( no irradiation ) and experimental ( irradiation ) , and according to Dukes ' pathological stage . The crude survival indicated no difference between the two groups , but analysis by stage and group demonstrated that for patients with a Dukes ' stage C lesion , 500 rads of cobalt-60 gamma irradiation a few hours before excision of the lesion approximately doubles the probability of survival at 5 years . The prospect of surgical cure is three times higher in cancers arising above the peritoneal reflection than in those arising below it . If the practice of abdominoperineal resection is to continue the authors recommend that preoperative irradiation become a routine procedure Objective The authors assessed the long-term effect of postoperative chemoradiotherapy on bowel function . Summary Background Data Adjuvant postoperative radiation therapy , often combined with chemotherapy , is being used increasingly often for rectal carcinoma . However , the long-term effect of this treatment on bowel function has not been investigated . Methods The records were review ed of all patients undergoing anterior resection for rectal carcinoma 2 to 5 years previously . During this period , patients with Astler-Coller stage B2 or C tumors generally were given postoperative radiation therapy with chemotherapy , whereas those with earlier stage tumors were not . To minimize possible confounding factors that may have been more common in the group receiving chemoradiotherapy and that may affect bowel function , extensive exclusion criteria were used , such as invasion of contiguous organs , local or distant metastases , use of a dysfunctfoning stoma , and anastomotic or pelvic complications . One hundred remaining patients were suitable for inclusion in the study and participated in a telephone question naire ; 41 patients had postoperative chemoradiotherapy , and 59 did not . Results The two groups were well matched for sex , level of anastomosis , and length of follow-up , although the group receiving chemoradiotherapy was slightly younger . The group that had chemoradiotherapy had more bowel movements per day than the group that did not have radiation therapy ( median 7 vs. median 2 , p < 0.001 ) ; the former group had “ clustering ” of bowel movements more often ( 42 % vs. 3 % , p < 0.001 ) , had nighttime movements more often ( 46 % vs. 14 % , p < 0.001 ) , had occasional or frequent incontinence more often ( 39 % and 17 % vs. 7 % and 0 % , p < 0.001 ) , wore a pad more often ( 41 % vs. 10 % , p < 0.001 ) , and were unable to defer defecation for more than 15 minutes more often ( 78 % vs. 19 % , p < 0.001 ) . The group that had chemoradiotherapy also had stool of liquid consistency , used antidiarrheal medications , had perianal skin irritation , were unable to differentiate stool from gas , and needed to defecate again within 30 minutes of a movement significantly more often than the group that did not receive chemoradiotherapy AIM Analysis of a r and omized study of preoperative radiation therapy for operable carcinoma of the rectum with regard to late sequelae . Results of tumor control and survival , which have already been published in detail are summarized for comparison and for confirmation of the conclusions . PATIENTS AND METHODS Between January 1988 and October 1993 94 patients with operable carcinoma of the rectum were included in a r and omized trial . Fourty-seven patients were treated with 5 x 3.3 Gy ( field size 16 x 16 cm , 9 MeV photons ) 24 to 48 hours prior to surgery ; 46 patients did not receive preoperative irradiation .  If risk factors ( T4-stage , R1/R2 resection , intraoperative tumor perforation ) were present , postoperative irradiation was performed after CT-planning . Total postoperative doses of 41.4 Gy ( preoperative irradiation ) or 59.8 Gy ( surgery only ) were applied with doses per fraction of 1.8 to 2.0 Gy . Local control , survival , and pattern of side effects were analyzed at 5 years after conclusion of the trial . RESULTS The frequency of local recurrence was markedly reduced by preoperative irradiation of R0-resected patients ( 24 % vs 13 % , p = 0.08 ) . The time to recurrence was delayed ( 1.9 vs 3 years ) . The 5-year actuarial survival rate was significantly higher in the preoperatively irradiated group compared to the not pre-irradiated group ( 40 % vs 28 % , p = 0.027 ) . Multivariate analysis revealed UICC-grading as the only independent parameter for local control ( p = 0.0003 ) , while preoperative irradiation ( p = 0.07 ) and T-stage ( p = 0.08 ) only displayed a trend . For patient survival , age ( p = 0.0003 ) . R-status ( p = 0.01 ) and UICC-score ( p = 0.001 ) were significant prognostic factors . Preoperative irradiation  had a non-significant effect only ( p = 0.078 ) . Radiation-induced side effects with a LENT-SOMA score > 2 were observed neither during frequent follow-up nor at an additional examination of those patients still alive in 1998 ( n = 25 ) . Of 4 pre- and postoperatively irradiated patients with risk factors , 3 had side effects grade 1 or 2 , predominantly rectal changes , at 5 to 11 years after treatment . CONCLUSIONS A positive effect on tumor control and survival is achieved with preoperative irradiation with the doses used in this study , with moderate side effects In a prospect i ve r and omized trial , 361 male patients with histologically proven adenocarcinoma of the rectum , judged preoperatively to require abdominoperineal resection ( APR ) , were treated by surgery alone or were given 3,150 rads of preoperative radiotherapy . Surgical resection was done on 320 patients , 262 having “ curative ” APR . Only moderate symptoms from radiotherapy were noted and postoperative complications and 30‐day mortality were similar in both groups . Five‐year survival for curative APR was the same in both groups ( 50 % for both treated and control patients ) . The incidence of positive lymph nodes in the resected specimens was 35 % in treated and 41 % in controls . In the first preoperative radiotherapy trial conducted by the group , 5‐year survival in patients undergoing “ curative ” APR was 47 % in treated versus 34 % in control groups . Additionally , the difference in positive lymph nodes in the resected specimens was substantially greater in the first trial ( 26 % in treated versus 44 % in controls ) . Cancer 58:352–359 , 1986 PURPOSE : The Swedish Rectal Cancer Trial has unequivocally demonstrated that preoperative high-dose ( 5 × 5 Gy ) radiotherapy reduces local failure rates and improves overall survival . This will have an impact on the primary treatment of rectal cancer . This study investigates the effect of preoperative high-dose radiotherapy on long-term bowel function in patients treated with anterior resection .  METHODS : A question naire was answered by 92 percent ( 203/220 ) of patients who were included in the Swedish Rectal Cancer Trial and who were alive after a minimum of five years . Thirty-two patients were excluded , mainly because of postoperative stomas and dementia , which left 171 for analysis . RESULTS : Median bowel frequency per week was 20 in the irradiated group ( n=84 ) and 10 in the surgery-alone group ( n=87;P<0.001 ) . Incontinence for loose stools ( P<0.001 ) , urgency ( P<0.001 ) , and emptying difficulties ( P<0.05 ) were all more common after irradiation . Sensory functions such as “ discrimination between gas and stool ” and “ ability to safely release flatus ” did not , however , differ between groups . Thirty percent of the irradiated group stated that they had an impaired social life because of bowel dysfunction , compared with 10 percent of the surgery-alone group ( P<0.01 ) 
    Output:
    
agent
***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: 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 A series of 103 consecutive rectal cancers was prospect ively documented . Laparotomy was performed in 78 patients of whom five did not undergo resection . Resection was considered curative unless there were liver metastases or biopsy‐proven residual disease . Nine patients had a palliative resection . Thus 64 patients underwent a curative resection , 52 ( 81 per cent ) of whom had an anterior resection of which 26 ( 46 per cent ) were performed by trainees . There were three deaths after operation . Eight ( 14 per cent ) patients developed a clinical anastomotic leak . Thirty patients were available for a minimum follow‐up of 24 ( mean 33 , range 24–49 ) months . Four ( 13 per cent ) patients developed distant recurrence . There were no isolated pelvic or anastomotic recurrences . One patient with distal recurrence may have had pelvic disease . The cumulative recurrence – free survival rate at 24 months was 84 per cent . These results support the suggestion that mesorectal excision may reduce local recurrence Adjuvant preoperative radiotherapy of patients with primary rectal carcinoma improves local control and survival , but also may increase the risk of early postoperative morbidity and mortality . In addition , the possible late adverse effects of this treatment are largely unknown From 1980 to 1985 , 471 patients with resectable rectal and rectosigmoid cancer were r and omly allocated to receive either preoperative short-term high-dose irradiation ( 25.5 Gy in one week ) for all patients or prolonged postoperative radiotherapy ( 60 Gy in seven to eight weeks ) only for patients with a Dukes B or C lesion . After a minimum follow-up of five years , the local recurrence rate was statistically significantly lower after preoperative than after postoperative radiotherapy ( 13 percentvs.22 percent;P=0.02 ) . No difference in overall survival was noted ( P=0.5 ) . To evaluate possible late side effects on the bowel , urinary bladder , or skin after surgery and additional preoperative or postoperative radiotherapy , all patients included in the r and omized trial , together with 58 patients from a preceding pilot study with the same preoperative regimen , were studied in a prolonged follow-up program . The hospital files of all patients were re-examined . Of the patients who were carefully examined , 176 had a survival exceeding five years and 19 had a survival exceeding 10 years . Overall , 7 percent ( 33/ 464 ) either were operated upon or have had a radiologic diagnosis of small bowel obstruction : 14/255 ( 5 percent ) after preoperative irradiation , 14/127 ( 11 percent ) after postoperative irradiation , and 5/82 ( 6 percent ) after surgery alone . The cumulative risk of developing a bowel obstruction was significantly increased after postoperative radiotherapy . Among the 98 patients alive after preoperative irradiation , significant morbidity from the bowel was noted in 11 patients , from the urinary bladder in two , and from the skin in six . In the postoperatively treated group of 34 patients , the bowel , urinary bladder , and skin morbidity were significant in five , two , and five patients , respectively . Corresponding morbidity in 44 nonirradiated patients was seen in five , one , and two patients , respectively . It is concluded that preoperative , short-term , high-dose radiotherapy decreases the local recurrence rate relative to postoperative radiotherapy , with no indications of increased late morbidity after a follow-up of 5 to 10 years The authors have studied the value of preoperative radiotherapy in 125 patients with cancer of the rectum . The patients were divided into two groups , control ( no irradiation ) and experimental ( irradiation ) , and according to Dukes ' pathological stage . The crude survival indicated no difference between the two groups , but analysis by stage and group demonstrated that for patients with a Dukes ' stage C lesion , 500 rads of cobalt-60 gamma irradiation a few hours before excision of the lesion approximately doubles the probability of survival at 5 years . The prospect of surgical cure is three times higher in cancers arising above the peritoneal reflection than in those arising below it . If the practice of abdominoperineal resection is to continue the authors recommend that preoperative irradiation become a routine procedure Objective The authors assessed the long-term effect of postoperative chemoradiotherapy on bowel function . Summary Background Data Adjuvant postoperative radiation therapy , often combined with chemotherapy , is being used increasingly often for rectal carcinoma . However , the long-term effect of this treatment on bowel function has not been investigated . Methods The records were review ed of all patients undergoing anterior resection for rectal carcinoma 2 to 5 years previously . During this period , patients with Astler-Coller stage B2 or C tumors generally were given postoperative radiation therapy with chemotherapy , whereas those with earlier stage tumors were not . To minimize possible confounding factors that may have been more common in the group receiving chemoradiotherapy and that may affect bowel function , extensive exclusion criteria were used , such as invasion of contiguous organs , local or distant metastases , use of a dysfunctfoning stoma , and anastomotic or pelvic complications . One hundred remaining patients were suitable for inclusion in the study and participated in a telephone question naire ; 41 patients had postoperative chemoradiotherapy , and 59 did not . Results The two groups were well matched for sex , level of anastomosis , and length of follow-up , although the group receiving chemoradiotherapy was slightly younger . The group that had chemoradiotherapy had more bowel movements per day than the group that did not have radiation therapy ( median 7 vs. median 2 , p < 0.001 ) ; the former group had “ clustering ” of bowel movements more often ( 42 % vs. 3 % , p < 0.001 ) , had nighttime movements more often ( 46 % vs. 14 % , p < 0.001 ) , had occasional or frequent incontinence more often ( 39 % and 17 % vs. 7 % and 0 % , p < 0.001 ) , wore a pad more often ( 41 % vs. 10 % , p < 0.001 ) , and were unable to defer defecation for more than 15 minutes more often ( 78 % vs. 19 % , p < 0.001 ) . The group that had chemoradiotherapy also had stool of liquid consistency , used antidiarrheal medications , had perianal skin irritation , were unable to differentiate stool from gas , and needed to defecate again within 30 minutes of a movement significantly more often than the group that did not receive chemoradiotherapy AIM Analysis of a r and omized study of preoperative radiation therapy for operable carcinoma of the rectum with regard to late sequelae . Results of tumor control and survival , which have already been published in detail are summarized for comparison and for confirmation of the conclusions . PATIENTS AND METHODS Between January 1988 and October 1993 94 patients with operable carcinoma of the rectum were included in a r and omized trial . Fourty-seven patients were treated with 5 x 3.3 Gy ( field size 16 x 16 cm , 9 MeV photons ) 24 to 48 hours prior to surgery ; 46 patients did not receive preoperative irradiation .  If risk factors ( T4-stage , R1/R2 resection , intraoperative tumor perforation ) were present , postoperative irradiation was performed after CT-planning . Total postoperative doses of 41.4 Gy ( preoperative irradiation ) or 59.8 Gy ( surgery only ) were applied with doses per fraction of 1.8 to 2.0 Gy . Local control , survival , and pattern of side effects were analyzed at 5 years after conclusion of the trial . RESULTS The frequency of local recurrence was markedly reduced by preoperative irradiation of R0-resected patients ( 24 % vs 13 % , p = 0.08 ) . The time to recurrence was delayed ( 1.9 vs 3 years ) . The 5-year actuarial survival rate was significantly higher in the preoperatively irradiated group compared to the not pre-irradiated group ( 40 % vs 28 % , p = 0.027 ) . Multivariate analysis revealed UICC-grading as the only independent parameter for local control ( p = 0.0003 ) , while preoperative irradiation ( p = 0.07 ) and T-stage ( p = 0.08 ) only displayed a trend . For patient survival , age ( p = 0.0003 ) . R-status ( p = 0.01 ) and UICC-score ( p = 0.001 ) were significant prognostic factors . Preoperative irradiation  had a non-significant effect only ( p = 0.078 ) . Radiation-induced side effects with a LENT-SOMA score > 2 were observed neither during frequent follow-up nor at an additional examination of those patients still alive in 1998 ( n = 25 ) . Of 4 pre- and postoperatively irradiated patients with risk factors , 3 had side effects grade 1 or 2 , predominantly rectal changes , at 5 to 11 years after treatment . CONCLUSIONS A positive effect on tumor control and survival is achieved with preoperative irradiation with the doses used in this study , with moderate side effects In a prospect i ve r and omized trial , 361 male patients with histologically proven adenocarcinoma of the rectum , judged preoperatively to require abdominoperineal resection ( APR ) , were treated by surgery alone or were given 3,150 rads of preoperative radiotherapy . Surgical resection was done on 320 patients , 262 having “ curative ” APR . Only moderate symptoms from radiotherapy were noted and postoperative complications and 30‐day mortality were similar in both groups . Five‐year survival for curative APR was the same in both groups ( 50 % for both treated and control patients ) . The incidence of positive lymph nodes in the resected specimens was 35 % in treated and 41 % in controls . In the first preoperative radiotherapy trial conducted by the group , 5‐year survival in patients undergoing “ curative ” APR was 47 % in treated versus 34 % in control groups . Additionally , the difference in positive lymph nodes in the resected specimens was substantially greater in the first trial ( 26 % in treated versus 44 % in controls ) . Cancer 58:352–359 , 1986 PURPOSE : The Swedish Rectal Cancer Trial has unequivocally demonstrated that preoperative high-dose ( 5 × 5 Gy ) radiotherapy reduces local failure rates and improves overall survival . This will have an impact on the primary treatment of rectal cancer . This study investigates the effect of preoperative high-dose radiotherapy on long-term bowel function in patients treated with anterior resection .  METHODS : A question naire was answered by 92 percent ( 203/220 ) of patients who were included in the Swedish Rectal Cancer Trial and who were alive after a minimum of five years . Thirty-two patients were excluded , mainly because of postoperative stomas and dementia , which left 171 for analysis . RESULTS : Median bowel frequency per week was 20 in the irradiated group ( n=84 ) and 10 in the surgery-alone group ( n=87;P<0.001 ) . Incontinence for loose stools ( P<0.001 ) , urgency ( P<0.001 ) , and emptying difficulties ( P<0.05 ) were all more common after irradiation . Sensory functions such as “ discrimination between gas and stool ” and “ ability to safely release flatus ” did not , however , differ between groups . Thirty percent of the irradiated group stated that they had an impaired social life because of bowel dysfunction , compared with 10 percent of the surgery-alone group ( P<0.01 ) 
    Output:
    