***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: Background The possible benefit for patients from follow‐up  examinations after curative surgery for colorectal cancer is unproven . The purpose of this study was to determine whether survival is improved by frequent follow‐up examinations Abstract Objective To determine the cost effectiveness of intensive follow up compared with conventional follow up in patients with colorectal cancer . Design Incremental cost effectiveness analysis recognising differences in follow up strategies , based on effectiveness data from a meta- analysis of five r and omised trials . Setting United Kingdom . Main outcome measures Taking a health service perspective , estimated incremental costs effectiveness ratios for each life year gained for five trials and four trials design ed for early detection of extramural recurrences ( targeted surveillance ) . Results Based on five year follow up , the numbers of life years gained by intensive follow up were 0.73 for the five trial model and 0.82 for the four trial model . For the five trials , the adjusted net ( extra ) cost for each patient was £ 2479 ( € 3550 ; $ 4288 ) and for each life year gained was £ 3402 , substantially lower than the current threshold of NHS cost acceptability ( £ 30 000 ) . The corresponding values for the four trial model were £ 2529 and £ 3077 , suggesting that targeted surveillance is more cost effective . The main predictor of incremental cost effectiveness ratios was surveillance costs rather than treatment costs . Judged against the NHS threshold of cost acceptability , the predicted incremental cost threshold was ninefold and the effectiveness threshold was 3 % . Conclusions Based on the available data and current costs , intensive follow up after curative resection for colorectal cancer is economically justified and should be normal practice . There is a continuing need to evaluate the efficacy of specific surveillance tools : this study forms the basis for economic evaluations in such trials Objective To assess whether colon cancer follow-up can be organised by general practitioners ( GPs ) without a decline in the patient 's quality of life ( QoL ) and increase in cost or time to cancer diagnoses , compared to hospital follow-up . Design R and omised controlled trial . Setting Northern Norway Health Authority Trust , 4 trusts , 11 hospitals and 88 local communities . Participants Patients surgically treated for colon cancer , hospital surgeons and community GPs . Intervention 24-month follow-up according to national guidelines at the community GP office . To ensure a high follow-up guideline adherence , a decision support tool for patients and GPs were used . Main outcome measures Primary outcomes were QoL , measured by the global health scales of the European Organisation for Research and Treatment of Cancer QoL Question naire ( EORTC QLQ C-30 ) and EuroQol-5D ( EQ-5D ) . Secondary outcomes were cost-effectiveness and time to cancer diagnoses . Results 110 patients were r and omised to intervention ( n=55 ) or control ( n=55 ) , and followed by 78 GPs ( 942 follow-up months ) and 70 surgeons ( 942 follow-up months ) , respectively . Compared to baseline , there was a significant improvement in postoperative QoL ( p=0.003 ) , but no differences between groups were revealed ( mean difference at 1 , 3 , 6 , 9 , 12 , 15 , 18 , 21 and 24-month follow-up appointments ) : Global Health ; Δ−2.23 , p=0.20 ; EQ-5D index ; Δ−0.10 , p=0.48 , EQ-5D VAS ; Δ−1.1 , p=0.44 . There were no differences in time to recurrent cancer diagnosis ( GP 35 days vs surgeon 45 days , p=0.46 ) ; 14 recurrences were detected ( GP 6 vs surgeon 8) and 7 metastases surgeries performed ( GP 3 vs surgeon 4 ) . The follow-up programme initiated 1186 healthcare contacts ( GP 678 vs surgeon 508 ) , 1105 diagnostic tests ( GP 592 vs surgeon 513 ) and 778 hospital travels ( GP 250 vs surgeon 528 ) . GP organised follow-up was associated with societal cost savings ( £ 8233 vs £ 9889 , p<0.001 ) . Conclusions GP-organised follow-up was associated with no decline in QoL , no increase in time to recurrent cancer diagnosis and cost savings . Trial registration Clinical Trials.gov identifier NCT00572143 BACKGROUND Intensive follow-up after surgery for colorectal cancer is common practice but lacks a firm evidence base . OBJECTIVE To assess whether or not augmenting symptomatic follow-up in primary care with two intensive methods of follow-up [ monitoring of blood carcinoembryonic antigen ( CEA ) levels and scheduled imaging ] is effective and cost-effective in detecting the recurrence of colorectal cancer treatable surgically with curative intent . DESIGN R and omised controlled open-label trial . Participants were r and omly assigned to one of four groups : ( 1 ) minimum follow-up ( n = 301 ) , ( 2 ) CEA testing only ( n = 300 ) , ( 3 ) computerised tomography ( CT ) only ( n = 299 ) or ( 4 ) CEA testing and CT ( n = 302 ) . Blood CEA  was measured every 3 months for 2 years and then every 6 months for 3 years ; CT scans of the chest , abdomen and pelvis were performed every 6 months for 2 years and then annually for 3 years . Those in the minimum and CEA testing-only arms had a single CT scan at 12 - 18 months . The groups were minimised on adjuvant chemotherapy , gender and age group ( three strata ) . SETTING Thirty-nine NHS hospitals in Engl and with access to high-volume services offering surgical treatment of metastatic recurrence . PARTICIPANTS A total of 1202 participants who had undergone curative treatment for Dukes ' stage A to C colorectal cancer with no residual disease .  Adjuvant treatment was completed if indicated . There was no evidence of metastatic disease on axial imaging and the post-operative blood CEA level was ≤ 10 µg/l . MAIN OUTCOME MEASURES Primary outcome Surgical treatment of recurrence with curative intent . Secondary outcomes Time to detection of recurrence , survival after treatment of recurrence , overall survival and quality -adjusted life-years ( QALYs ) gained . RESULTS Detection of recurrence During 5 years of scheduled follow-up , cancer recurrence was detected in 203 ( 16.9 % ) participants . The proportion of participants with recurrence surgically treated with curative intent was 6.3 % ( 76/1202 ) , with little difference according to Dukes ' staging ( stage A , 5.1 % ; stage B , 7.4 % ; stage C , 5.6 % ; p = 0.56 ) . The proportion was two to three times higher in each of the three more intensive arms ( 7.5 % overall ) than in the minimum follow-up arm ( 2.7 % ) ( difference 4.8 % ; p = 0.003 ) . Surgical treatment of recurrence with curative intent was 2.7 % ( 8/301 ) in the minimum follow-up group , 6.3 % ( 19/300 ) in the CEA testing group , 9.4 % ( 28/299 ) in the CT group and 7.0 % ( 21/302 ) in the CEA testing and CT group . Surgical treatment of recurrence with curative intent was two to three times higher in each of the three more intensive follow-up groups than in the minimum follow-up group ; adjusted odds ratios ( ORs ) compared with minimum follow-up were as follows : CEA testing group , OR 2.40 , 95 % confidence interval ( CI ) 1.02 to 5.65 ; CT group , OR 3.69 , 95 % CI 1.63 to 8.38 ; and CEA testing and CT group , OR 2.78 , 95 % CI 1.19 to 6.49 . Survival A Kaplan-Meier survival analysis confirmed no significant difference between arms ( log-rank p = 0.45 ) . The baseline-adjusted Cox proportional hazards ratio comparing the minimum and intensive arms was 0.87 ( 95 % CI 0.67 to 1.15 ) . These CIs suggest a maximum survival benefit from intensive follow-up of 3.8 % . Cost-effectiveness The incremental cost per patient treated surgically with curative intent compared with minimum follow-up was £ 40,131 with CEA testing , £ 43,392 with CT and £ 85,151 with CEA testing and CT . The lack of differential impact on survival result ed in little difference in QALYs saved between arms . The additional cost per QALY gained of moving from minimum follow-up to CEA testing was £ 25,951 and for CT was £ 246,107 . When compared with minimum follow-up , combined CEA testing and CT was more costly and generated fewer QALYs , result ing in a negative incremental cost-effectiveness ratio ( -£208,347 ) and a dominated policy . LIMITATIONS Although this is the largest trial undertaken at the time of writing , it has insufficient power to assess whether or not the improvement in detecting treatable recurrence achieved by intensive follow-up leads to a reduction in overall mortality . CONCLUSIONS Rigorous staging to detect residual disease is important before embarking on follow-up . The benefit of intensive follow-up in detecting surgically treatable recurrence is independent of stage . The survival benefit from intensive follow-up is unlikely to exceed 4 % in absolute terms and harm can not be absolutely excluded . A longer time horizon is required to ascertain whether or not intensive follow-up is an efficient use of scarce health-care re sources . Translational analyses are under way , utilising tumour tissue collected from Follow-up After Colorectal Surgery trial participants , with the aim of identifying potentially prognostic biomarkers that may guide follow-up in the future . TRIAL REGISTRATION Current Controlled Trials IS RCT N41458548 . FUNDING This project was funded by the National Institute for Health Research ( NIHR ) Health Technology Assessment programme and will be published in full in Health Technology Assessment ; Vol . 21 , No. 32 . See the NIHR Journals Library website for further project information BACKGROUND Although colonoscopy plays an important role in postoperative surveillance of patients with colorectal cancer , the optimum protocol for colonoscopic surveillance has not been established . OBJECTIVE Our purpose was to compare the efficacy of 2 different colonoscopic surveillance strategies in terms of both survival and recurrence resectability . DESIGN Prospect i ve , r and omized , controlled trial . SETTING A teaching hospital in Sun Yat-sen University . PATIENTS Three hundred twenty-six consecutive patients undergoing radical surgery for colorectal cancer . INTERVENTION In the intensive colonoscopic surveillance group ( ICS group , n = 165 ) , colonoscopy was performed at 3-month intervals for 1 year , at 6-month intervals for the next 2 years , and once a year thereafter . In the routine colonoscopic surveillance group ( RCS group , n = 161 ) , colonoscopy was performed at 6 months , 30 months , and 60 months postoperatively . MAIN OUTCOME MEASUREMENTS AND RESULTS The 5-year survival rate was 77 % in the ICS group and 73 % in the RCS group ( P > .05 ) . Postoperative colorectal cancer was detected in 13 patients ( 8.1 % ) in the ICS group and in 18 patients ( 11.4 % ) in the RCS group . In the ICS group , there were more asymptomatic postoperative colorectal cancers ( P = .04 ) , more patients had reoperation with curative intent ( P = .048 ) , and the probability of survival after postoperative colorectal cancer was higher ( P = .03 ) . LIMITATION Lack of detailed characterization of metachronous colorectal adenomas in these patients . CONCLUSIONS Although the patients in the ICS group had more curative operations for postoperative colorectal cancer and survived significantly longer , ICS itself did not improve overall survival OBJECTIVE To determine whether an intensified follow-up of patients with colorectal cancer can lead to improved reresectability and a better long-term survival . DESIGN A prospect i ve r and omized trial of 106 patients . SETTING Oulu University Hospital , a referral center in northern Finl and . PATIENTS A total of 106 consecutive patients who underwent radical resection for colorectal cancer , 54 of whom were r and omized into a conventional follow-up group and 52 into an intensified follow-up group .  MAIN OUTCOME MEASURES After a 5-year follow-up , the time of detection of recurrence , the recurrence rates , the first method showing recurrence , the mode of recurrence , reresectability , and survival were compared between the groups . RESULTS The recurrences were identified earlier in the intensified follow-up group than in the conventional follow-up group ( mean + /- SD , 10 + /- 5 months vs 15 + /- 10 months ) . The overall recurrence rate was 41 % , with 39 % in the conventional group and 42 % in the intensified group . Carcinoembryonic antigen determination was the most common method showing recurrence in both groups . Endoscopy and ultrasound were beneficial in the intensified follow-up group , but computed tomography failed to improve the diagnostics . The mode of recurrence did not differ between the groups . Radical resections were performed on 19 % ( 8/ 
    Output:
    
For patients with nonmetastatic colorectal cancer after curative resection , intensive follow-up strategy was associated with an improvement in overall survival compared with less follow-up strategy .
Intensive-frequency follow-up strategy was associated with a greater reduction in mortality compared with intensive-test follow-up strategy