***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 Investigators have proposed " predict , resect , and discard " strategies for diminutive ( ≤ 5 mm ) or small ( 6 - 9 mm ) polyps to reduce screening colonoscopy costs . Advanced histological features such as villous histology , high- grade dysplasia , and /or cancer in these polyps could deter adoption of these strategies . OBJECTIVE Determine the prevalence of advanced histological features in diminutive and small colon polyps . DESIGN Retrospective analysis of data from 3 prospect i ve clinical trials . SETTING Two tertiary-care referral centers . PATIENTS This study involved patients undergoing screening or surveillance colonoscopy .  INTERVENTION The location , size , and morphology of each polyp detected was documented . Each polyp was then resected , placed in a unique specimen jar , and sent for histopathological evaluation . MAIN OUTCOME MEASUREMENTS Rates of advanced histological features ( villous histology , high- grade dysplasia , and cancer ) . RESULTS A total of 2361 polyps were detected , removed , and retrieved . Both diminutive and small polyps had a lower frequency of any advanced histological features compared with large polyps ( 0.5 % and 1.5 % , respectively vs 15.0 % ; P < .001 for both comparisons ) . Polyps < 10 mm in size had a lower frequency of advanced histology compared with polyps ≥ 10 mm ( 0.8 % vs 15.0 % ; P < .001 ) . During sensitivity analysis , the frequency of advanced histological features varied from 0.2 % to 0.7 % within diminutive polyps , 1.5 % to 3.6 % within small polyps , and 0.8 % to 1.2 % within polyps < 10 mm . LIMITATIONS Retrospective analysis from tertiary-care referral centers ; predominantly white , male , veteran patient population result ing in limited generalizability of results . CONCLUSION The prevalence of advanced histological features in colon polyps ≤ 5 mm is very low ( 0.5 % ) . This has important implication s for the potential practice of " predicting , resecting , and discarding " diminutive colon polyps Objective : Colonoscopy is the accepted gold st and ard for screening of neoplastic colorectal lesions , but the substantial miss rate remains a challenge . Computed virtual chromoendoscopy with the Fujinon intelligent colour enhancement ( FICE ) system is a new dyeless imaging technique that might allow higher rates of adenoma detection . Methods : This is a prospect i ve r and omised five tertiary care centre trial of colonoscopy in the FICE mode versus st and ard colonoscopy with targeted indigocarmine chromoscopy ( control group ) in consecutive patients attending for routine colonoscopy .  Histopathology of detected lesions was confirmed by evaluation of endoscopic resection or biopsy specimens . Results : 871 patients were enrolled , and 764 patients ( 344 female , mean age 64 years ) were subjected to final analysis ( 368 in the FICE group , 396 in the control group ) . In total , 236 adenomas ( mean of 0.64 per case ) were detected in the FICE group and 271 adenomas ( mean of 0.68 per case ) in the control group ( p = 0.92 ) . There was no statistically significant difference in the percentage of patients with ⩾1 adenoma between the control group ( 35.4 % ) and the FICE group ( 35.6 % ) ( p = 1.0 ) . For the differential diagnosis of adenomas and non-neoplastic polyps , the sensitivity of FICE ( 92.7 % ) was comparable with that of indigocarmine ( 90.4 % ) ( p = 0.44 ) . Conclusions : At colonoscopy , adenoma detection rates are not improved by virtual chromoendoscopy with the FICE system compared with white light endoscopy with targeted indigocarmine spraying . However , FICE can effectively substitute for chromoscopy concerning the differentiation of neoplastic and non-neoplastic lesions BACKGROUND Probe-based confocal laser endomicroscopy ( pCLE ) is an emerging tool for in vivo imaging of the GI tract that requires the endoscopist to interpret microscopic images . The learning curve for interpretation of pCLE images is unknown . OBJECTIVE To examine the learning curve of correctly identifying benign and neoplastic colorectal lesions by using pCLE and to evaluate the learning curve of obtaining high- quality images . DESIGN Prospect i ve , double-blind review of pCLE images of 76 colorectal lesions by using corresponding polypectomies as the reference st and ard . A training set of 20 images with known histology was first review ed to st and ardize image interpretation , followed by blinded review of 76 unknown images . SETTING Eleven endoscopists from 3 different endoscopy centers evaluated the images obtained by 1 endoscopist using the high-definition confocal probe .  PATIENTS Patients undergoing screening and surveillance colonoscopies . INTERVENTION Intravenous fluorescein pCLE imaging of colorectal lesions followed by polypectomies . MAIN OUTCOME MEASUREMENTS Accuracy of image interpretation with constructing learning curve for pCLE image interpretation and acquisition . RESULTS Of the 76 colorectal lesions , 51 ( 67 % ) were neoplastic and 25 ( 33 % ) were benign , based on histopathology . Accuracy for the overall group was 63 % for lesions 1 to 20 , 64 % for lesions 21 to 40 , 79 % for lesions 41 to 60 , and 86 % for lesions 61 to 76 . The ability to obtain high- quality images was stable over the 76 cases . LIMITATIONS Small sample size and use of offline video sequences . CONCLUSIONS Accurate interpretation of pCLE images for predicting neoplastic lesions can be learned rapidly by a wide range of GI specialists . Furthermore , the ability to acquire high- quality pCLE images is also quickly learned BACKGROUND The EPKi system ( Pentax , Japan ) enables resolution above HDTV . Aim of the study was to test the efficacy of HD+ alone and with the new post-processing digital filter i-Scan or chromoendoscopy ( Methylene blue 0.1 % ) in screening for colorectal cancer . We focused on lesions less than 5 mm as a surrogate marker for the optical possibilities of the EPKi system . METHODS The last 30 cm of the colon in a screening population were inspected with HD+ alone , in combination with i-Scan ( 2:1 r and omisation ) and subsequently with chromoendoscopy . All lesions were characterized and targeted biopsies were performed . RESULTS i-Scan  augmented in 69 patients the identification of lesions from 176 to 335 ( p<0.001 ) and chromoendoscopy to 646 ( p<0.001 ) . The additional lesions were mainly flat ( type IIb , 74 % ) , which were only recognized using i-Scan or chromoendoscopy . The amount of neoplasias was not significantly different ( HD+ : 5 , i-Scan : 11 , Chromoendoscopy : 11 ) , but all could correctly be predicted using i-Scan or chromoendoscopy . CONCLUSIONS HD+ colonoscopy with and without i-Scan unmask a plethora of small lesions but chromoendoscopy can even advance the number . However , i-Scan was able to predict neoplasia as precisely as chromoendoscopy and might shortly replace chromoendoscopy as a more time efficient tool BACKGROUND AND STUDY AIMS Narrow-b and imaging ( NBI ) has shown promising results in discriminating adenomatous from non-adenomatous colonic polyps . In patients with small polyps ( < 10 mm ) , the application of NBI within a " resect and discard " strategy , might allow post-polypectomy surveillance intervals to be determined independently from histopathology . The aim of the present study was to assess the feasibility and safety of this approach in routine clinical practice . PATIENTS AND METHODS Consecutive colonoscopy out patients with one or more polyps smaller than 10 mm were prospect ively included . Each polyp was categorized by the endoscopist as adenoma or non-adenoma according to simplified NBI criteria , and future post-polypectomy surveillance interval was assigned accordingly . Following histopathology ,  post-polypectomy surveillance interval was subsequently re-assigned , and the accordance between endoscopy- and histology-directed surveillance  strategies was calculated . RESULTS Among 942 colonoscopy patients , 286 ( 30.4 % ) with only small polyps were included . In total , 511 small polyps were evaluated ; 350 ( 68.5 % ) were adenomas and 18 of these ( 5.1 % ) had histologic features of advanced neoplasia . For the in vivo diagnosis of adenoma , NBI sensitivity , specificity , accuracy , and positive and negative likelihood ratios were 94.9 % , 65.8 % , 85.7 % , 2.80 , and 0.08 , respectively . The endoscopy-directed surveillance strategy was in accordance with the  histology-directed strategy in 237 of 286 patients ( 82.9 % ) . In 9.8 % and 7.3 % patients , the endoscopy-directed approach would have result ed in early and delayed surveillance , respectively . CONCLUSIONS The resect and discard strategy seems to be a viable , safe , and cost-effective approach for the management of patients with small polyps . However , caution in the application of the strategy should be advocated for patients with polyps 6 - 9 mm in size and those with right-sided lesions , due to their malignant potential . The study was registered on Clinical trials.gov ( NCT01462123 ) Background and study aims Magnifying colonoscopy with indigo carmine dye and the analysis of the capillary and the pit patterns by computed virtual chromoendoscopy ( Fujinon Intelligent Color Enhancement , FICE ) with magnification are effective for the differential diagnosis of neoplastic and non-neoplastic lesions . This study aim ed to compare the accuracy of virtual and real chromoendoscopy in differentiating neoplastic and non-neoplastic colorectal lesions . Patients and methods A prospect i ve r and omized trial of magnification colonoscopy with targeted FICE  ( Group I – 72 patients /111 lesions ) versus magnification colonoscopy with targeted indigo carmine dye  ( Group II – 72 patients /137 lesions ) was performed in consecutive patients with lesions 1 cm or less . Histopathology of the specimens was regarded as the gold st and ard . Results In group I , 86 ( 77.5 % ) lesions showed an intense vascular pattern ( positive capillary meshwork ) , of which 80 ( 93 % ) were histologically confirmed as adenomas . From 25 lesions with negative capillary meshwork , 23 ( 92 % ) were non-neoplastic . Sensitivity , specificity , accuracy , positive and negative predictive values of the capillary meshwork for the differential diagnosis of these lesions was 97.8 , 79.3 , 92.8 , 93 and 92 % , respectively . The same parameters for pit pattern analysis by FICE were 92.7 , 82.3 , 90.1 , 93.8 and 80 % , respectively . Indigo carmine magnified chromoscopy showed sensitivity , specificity , accuracy , positive and negative predictive values of 97 , 88.9 , 94.9 , 96.1 and 91.4 % , respectively in the discrimination between neoplastic and non-neoplastic lesions . Conclusion Magnified virtual chromoendoscopy is as accurate as indigo carmine magnified chromoendoscopy in distinguishing between neoplastic from non-neoplastic small colorectal lesions BACKGROUND Digital chromoendoscopy ( DCE ) has the potential for the in vivo optical diagnosis of colon polyps . However , no comparison of different DCE technologies currently exists . OBJECTIVE To compare the diagnostic efficacies of narrow-b and imaging ( NBI ) with those of I-Scan for the real-time histological prediction of diminutive colonic polyps ( DCPs ) ( ≤5 mm ) by using the simple unified endoscopic classification . DESIGN Prospect i ve cohort study . SETTING Academic hospital . PATIENTS In total , 296 DCPs from 142 patients undergoing screening or surveillance colonoscopy were assessed . INTERVENTIONS All DCPs detected during withdrawal were evaluated for the surface details by using high-definition white-light colonoscopy , and thereafter by using DCE ( NBI or I-Scan ) without optical magnification . The histology of all polyps was predicted in real-time and confirmed through the evaluation of biopsy or polypectomy specimens . MAIN OUTCOME MEASUREMENTS Diagnostic efficacies of NBI and I-Scan . RESULTS NBI and I-Scan displayed a significantly higher sensitivity and improved accuracy compared with high-definition white-light colonoscopy for the prediction of adenomas ( P < .05 ) . No significant differences were evident between the NBI and I-Scan ( sensitivity , 88.8 % vs 94.6 % ; specificity , 86.8 % vs 86.4 % ; accuracy , 87.8 % vs 90.7 % , respectively ; P > .05 ) . Additionally , substantial levels of intra- and interobserver agreement between the NBI and I-Scan were measured ( κ values > 0.7 ) . LIMITATIONS No r and omized or 
    Output:
    
Our meta-analyses indicate that optical biopsy with NBI , exceeds the NPV threshold for adenomatous polyp histology , supporting a " diagnose- and -leave " strategy for diminutive predicted nonneoplastic polyps in the rectosigmoid colon .