***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: All 68,308 inhabitants of Göteborg born between 1918 and 1931 were r and omly divided into a test and a control group . The subjects in the test group were invited to perform Hemoccult II fecal occult blood testing  on 3 days and to repeat the test after 16 to 24 months . In the prevalence screening 21,347 ( 63 % ) performed the test , and in the rescreening 19,991 ( 60 % ) . Investigation of the 942 ( 4.4 % ) with positive tests in the prevalence screening showed 47 cancers and 129 subjects with adenomas > or = 1.0 cm . In the rescreening 5.1 % had a positive test , and 34 cancers and 122 subjects with adenomas ( > or = 1.0 cm ) were found among those . Cancer had also been diagnosed in 19 subjects in the interval between the two screening occasions and in 15 subjects among the non-responders . Forty-four cancers had been diagnosed in the control group during the same period . Cancers detected by screening were at a less advanced stage than in the control group . It is too early to show any effect of  screening  on mortality from colorectal cancer Purpose Fecal immunochemical tests ( FITs ) have been developed to address analytical problems inherent in the older guaiac-based fecal occult blood tests ( g-FOBTs ) . Our aim was to compare the performance characteristics of one g-FOBT ( Hemoccult II ) and two FITs ( the Hemoccult ICT and MagStream HemSp ) relative to colonoscopy for the detection of colorectal cancer and significant precursor lesions . We also examined whether a 1-day collection strategy would negatively impact test diagnostic performance . Methods We used a prospect i ve observational cohort design in a Canadian population eligible for screening . All participants received colonoscopy after performing the occult blood tests . Results One thous and seventy-five individuals were enrolled ( mean age 56.3 years , 53.8 % females ) . Using colonoscopy as the gold st and ard , the sensitivity for screen-relevant neoplasm was determined for Hemoccult II ( 7.2 , 95 % CI : 1.1–13.4 ) , Hemoccult ICT ( 23.2 % : 13.2–33.1 ) , and MagStream HemSp using 67 μg/gram stool as the cut-off ( 23.2 % : 13.2–33.1 ) . The Magstream HemSp , using a cut-off threshold of 30 μg/gram stool , had the lowest specificity at 87.6 % ( 85.4–89.6 ) , while the Hemoccult II had the highest at 98.8 % ( 98.1–99.5 ) . Single-day stool testing reduced the false-positive rates of all tests without significantly reducing the sensitivity . Conclusion We found that FITs have a significantly increased sensitivity but reduced specificity for screen-relevant neoplasm compared to g-FOBT using colonoscopy as the gold st and ard . Optimal threshold levels for hemoglobin detection depend on the desired trade off between sensitivity and false-positive rate . Single-day testing with an FIT may be an option to enhance population compliance with screening BACKGROUND & AIMS Fecal DNA testing has shown greater sensitivity than guaiac-based occult blood tests for noninvasive colorectal cancer ( CRC ) screening . The prototype assay ( version 1 ) , which analyzed 22 gene mutations and DNA integrity assay ( DIA ) , showed a sensitivity of 52 % for CRC detection and a specificity of 94 % in average-risk individuals . The present study was conducted to determine the sensitivity and specificity of a second-generation assay ( version 2 ) that uses improved DNA stabilization/isolation techniques and a new promoter methylation marker . METHODS Forty patients with CRC and 122 subjects with normal colonoscopy provided stool sample s to which DNA preservation buffer was added immediately . DNA was purified using gel-based capture , and analyzed for the original panel of 22 mutations , DIA , and 2 new promoter methylation markers . RESULTS By using DNA that was optimally preserved and purified from stool , the sensitivity of the prototype version 1 assay increased to 72.5 % because of enhanced performance of DIA . Vimentin gene methylation alone provided sensitivity and specificity of 72.5 % and 86.9 % , respectively . The optimal combination of vimentin methylation plus DIA result ed in 87.5 % sensitivity and 82 % specificity ; cancers were detected regardless of stage or location . False-positive vimentin methylation was associated with older age . CONCLUSIONS An improved fecal DNA test that incorporates only 2 markers shows much higher sensitivity for CRC . The new assay is easier to perform and should be less costly , thereby facilitating its use for noninvasive CRC screening OBJECTIVES To determine if participation in colorectal cancer screening using faecal occult blood testing ( FOBT ) is affected by a restrictive diet and if it is associated with certain demographic variables . PARTICIPANTS AND SETTING 1,203 residents of South Australia aged 50 - 69 years , with no " currently active bowel disease " , r and omly selected from a data base of people willing to be contacted about unspecified health issues . DESIGN R and omised controlled trial : participants were offered screening by immunochemical FOBT by mail in 1998 . Half were r and omly allocated to a group instructed to follow a low-peroxidase diet , as required for guaiac FOBT , while the other group was not so restricted . MAIN OUTCOME MEASURES Effect of diet restriction on participation ( return of correctly completed FOBT sample cards within 15 weeks ) ; time taken to return cards ; relationships between participation and demographic variables . RESULTS Participation rates were 65.9 % ( no-diet group ) and 53.3 % ( diet group ) ( difference , 12.6 % ; 95 % CI , 7.1%-18.1 % ) . In the first week , rates of return as a proportion of all tests returned were 13.1 % ( no-diet ) and 1.6 % ( diet ) ( difference , 11.5 % ; 95 % CI , 8.6%-14.4 % ) , increasing to 54.3 % and 44.5 % , respectively , after five weeks ( difference , 9.8 % ; 95 % CI , 4.2%-15.4 % ) . Participation was significantly associated with older age ( odds ratio , 1.40 ; 95 % CI , 1.10 - 1.78 ) , but not sex , Index of Social Disadvantage or rural versus urban address . CONCLUSIONS Dietary restrictions create a barrier to FOBT-based screening for colorectal cancer . The use of immunochemical rather than guaiac FOBT removes this barrier Colorectal cancer is the second-leading cause of cancer death . New noninvasive options for screening capable of diagnosing cancer at an early stage are needed to improve compliance and reduce mortality . This study was design ed to provide an estimate of the sensitivity and specificity of a multitarget assay panel ( MTAP ) of stool DNA changes .  Eighty patients with advanced colorectal neoplasia and 212 control subjects provided stool sample s before colonoscopy . Patients with hereditary colorectal cancer syndromes were excluded . The MTAP included 21 specific mutations in the adenomatous polyposis coli ( APC ) , p53 , and K-ras genes , a microsatellite instability marker ( BAT-26 ) , and a marker of abnormal apoptosis ( DNA Integrity Assay ) . All sample s were analyzed in the clinical laboratory at EXACT Sciences . Multitarget assay panel detected 33 of 52 patients ( 63.5 % , 95 % confidence interval [ CI ] , 49.0%-76.4 % ) with invasive colorectal cancer , including 26 of 36 ( 72.2 % ) with node-negative disease ( American Joint Committee on Cancer [ AJCC ] stage I/II ) and 7 of 16 ( 43.7 % ) with advanced disease ( AJCC stage III/IV ) . Sixteen of 28 patients ( 57.1 % ; 95 % CI , 37.2%-75.5 % ) with advanced adenomas ( lesions containing high- grade dysplasia , villous adenomas , or tubular adenomas > 1 cm in size ) were detected , including 6 of 7 ( 85.7 % ) with high- grade dysplasia and 10 of 21 ( 47.6 % ) with other advanced adenomas . Specificity was 96.2 % ( 95 % CI , 92.7%-98.4 % ) in patients with either no colorectal lesions or diminutive polyps . Multitarget assay panel has better sensitivity than that reported with use of Hemoccult(R ) II in fecal occult blood testing , with similar specificity . Sensitivity appeared to be equally high for patients with node-negative and advanced disease , as well as for advanced adenomas . This study contained a disproportionately high number of distal cancers and , as such , may not be representative of results in proximal lesions . Although a prospect i ve study in an average-risk population is needed to vali date these findings , MTAP may offer an important noninvasive option for population -based screening BACKGROUND Although fecal occult-blood testing is the only available noninvasive screening method that reduces the risk of death from colorectal cancer , it has limited sensitivity . We compared an approach that identifies abnormal DNA in stool sample s with the Hemoccult II fecal occult-blood test in average-risk , asymptomatic persons 50 years of age or older . METHODS Eligible subjects su bmi tted one stool specimen for DNA analysis  , underwent st and ard Hemoccult II testing , and then underwent colonoscopy . Of 5486 subjects enrolled , 4404 completed all aspects of the study . A subgroup of 2507 subjects was analyzed , including all those with a diagnosis of invasive adenocarcinoma or advanced adenoma plus r and omly chosen subjects with no polyps or minor polyps . The fecal DNA panel consisted of 21 mutations . RESULTS The fecal DNA panel detected 16 of 31 invasive cancers , whereas Hemoccult II identified 4 of 31 ( 51.6 percent vs. 12.9 percent , P=0.003 ) . The DNA panel detected 29 of 71 invasive cancers plus adenomas with high- grade dysplasia , whereas Hemoccult II identified 10 of 71 ( 40.8 percent vs. 14.1 percent , P<0.001 ) . Among 418 subjects with advanced neoplasia ( defined as a tubular adenoma at least 1 cm in diameter , a polyp with a villous histologic appearance , a polyp with high- grade dysplasia , or cancer ) , the DNA panel was positive in 76 ( 18.2 percent ) , whereas Hemoccult II was positive in 45 ( 10.8 percent ) . Specificity in subjects with negative findings on colonoscopy was 94.4 percent for the fecal DNA panel and 95.2 percent for Hemoccult II . CONCLUSIONS Although the majority of neoplastic lesions identified by colonoscopy were not detected by either noninvasive test , the multitarget analysis of fecal DNA detected a greater proportion of important colorectal neoplasia than did Hemoccult II without compromising specificity BACKGROUND One type of fecal occult blood test ( FOBT ) , the unrehydrated guaiac fecal occult blood test ( GT ) , is recommended by the United States Preventive Services Task Force and the Institute of Medicine for use in screening programs , but it has relatively low sensitivity as a single test for detecting advanced colonic neoplasms ( cancer and adenomatous polyps > or = 1 cm in diameter ) . Thus , improving the sensitivity of FOBT should make colon cancer screening programs that use these tests more effective . METHODS We assessed prospect ively the performance characteristics of two newer FOBTs in 5841 subjects at average risk for colorectal cancer in a large group-model managed care organization . The tests evaluated included a sensitive GT , a fecal immunochemical test ( FIT ) , and the combination of both tests . Patients with positive and negative test results were advised to have colonoscopy and sigmoidoscopy , respectively . Sensitivity and specificity for detecting advanced neoplasms in the left colon within 2 years after the FOBT screening were evaluated for the two tests administered separately and in combination . RESULTS A total of 139 patients were diagnosed with advanced colorectal neoplasms ( n = 14 cancers , n = 128 adenomas ) within the 2 years following their initial  FOBT screening .  Sensitivity for detecting cancer was 81.8 % ( 95 % confidence interval [ CI ] = 47.8 % to 96.8 % ) for the FIT alone and 64.3 % ( 95 % CI = 35.6 % to 86.0 % ) for the sensitive GT and the combination test . Sensitivity for detecting advanced colorectal adenomas was 41.3 % ( 95 % CI = 32.7 % to 50.4 % ) for the sensitive GT , 29.5 % ( 95 % CI = 21.4 % to 38.9 % ) for the FIT , and 22.8 % ( 95 % CI = 16.1 % to 31.3 % ) for the combination test . Specificity for detecting cancer and adenomas was 98. 
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Conclusion On the basis of the available ( albeit limited ) evidence , while fDNA is cost-effective when compared with no screening , it is currently dominated by most of the other available screening options .
Cost and test performance appear to be the main influences on cost-effectiveness