Detecting diminutive colorectal lesions at colonoscopy: a randomised controlled trial of pan-colonic versus targeted chromoscopy. Chromoendoscopy detects more adenomas than colonoscopy using intensive inspection without dye spraying. Does chromoendoscopy with structure enhancement improve the colonoscopic adenoma detection rate? Postoperative surveillance in patients with colorectal cancer who have undergone curative resection: a prospective, multicenter, randomized, controlled trial. High resolution colonoscopy with chromoscopy versus standard colonoscopy for the detection of colonic neoplasia: a randomized study. The risks of screening: data from the Nottingham randomised controlled trial of faecal occult blood screening for colorectal cancer. Comparative study of conventional colonoscopy and pan-colonic narrow-band imaging system in the detection of neoplastic colonic polyps: a randomized, controlled trial. Is colonoscopic surveillance reducing colorectal cancer mortality in ulcerative colitis? A population based case control study. Colonoscopic surveillance reduces mortality from colorectal cancer in ulcerative colitis.
Diminutive and flat colorectal lesions can be difficult to detect using conventional colonoscopic techniques. Previous data have suggested that pan-chromoscopy may improve detection rates. No randomised control trial has been performed examining detection rates of such lesions while controlling for extubation time and lavage effect.
                We conducted a randomised controlled trial of pan-colonic chromoscopic colonoscopy for the detection of diminutive and flat colorectal lesions while controlling for extubation time and lavage effect.
                Consecutive patients attending for routine colonoscopy were randomised to either pan-chromoscopy using 0.5% indigo carmine (IC) or targeted chromoscopy (control group). A minimum diagnostic extubation time was set at eight minutes with controls undergoing a matched volume of saline wash.
                A total of 260 patients were randomised; 132 controls and 128 to pan-colonic chromoscopy. Extubation times did not differ significantly between the control (median 15 minutes (range 8-41)) and chromoscopy (median 17 minutes (range 8-39)) groups. The volume of IC used in the pan-chromoscopy group (median 68 ml (range 65-90)) and normal saline used in the control group (69 ml (range 60-93)) did not differ significantly. There was a statistically significant difference between the groups regarding the total number of adenomas detected (p<0.05) with significantly more diminutive (<4 mm) adenomas detected in the pan-chromoscopy group (p = 0.03). Pan-chromoscopy diagnosed more diminutive and flat lesions in the right colon compared with controls (p<0.05), with more patients with multiple adenomas (>3) detected using pan-chromoscopy (p<0.01). Hyperplastic lesions were more commonly detected in the pan-chromoscopy group compared with controls (p<0.001). More hyperplastic polyps were detected in the left colon (86% rectosigmoid) using chromoscopy compared with controls.
                Chromoscopy improves the total number of adenomas detected and enhances the detection of diminutive and flat lesions. Importantly, eight diminutive lesions had foci of high grade dysplasia. Chromoscopy may benefit patients, assuming a high risk of colorectal cancer, and help in risk stratification and planning follow up colonoscopy intervals. Conventional colonoscopy misses some neoplastic lesions. We compared the sensitivity of chromoendoscopy and colonoscopy with intensive inspection for detecting adenomatous polyps missed by conventional colonoscopy. Fifty subjects with a history of colorectal cancer or adenomas underwent tandem colonoscopies at one of five centers of the Great Lakes New England Clinical Epidemiology and Validation Center of the Early Detection Research Network. The first exam was a conventional colonoscopy with removal of all visualized polyps. The second exam was randomly assigned as either pan-colonic indigocarmine chromoendoscopy or standard colonoscopy with intensive inspection lasting >20 minutes. Size, histology, and numbers of polyps detected on each exam were recorded. Twenty-seven subjects were randomized to a second exam with chromoendoscopy and 23 underwent intensive inspection. Forty adenomas were identified on the first standard colonoscopies. The second colonoscopies detected 24 additional adenomas: 19 were found using chromoendoscopy and 5 were found using intensive inspection. Chromoendoscopy found additional adenomas in more subjects than did intensive inspection (44% versus 17%) and identified significantly more missed adenomas per subject (0.7 versus 0.2, P < 0.01). Adenomas detected with chromoendoscopy were significantly smaller (mean size 2.66 +/- 0.97 mm) and were more often right-sided. Chromoendoscopy was associated with more normal tissue biopsies and longer procedure times than intensive inspection. After controlling for procedure time, chromoendoscopy detected more adenomas and hyperplastic polyps compared with colonoscopy using intensive inspection alone. Chromoendoscopy detected more polyps missed by standard colonoscopy than did intensive inspection. The clinical significance of these small missed lesions warrants further study. Colonoscopy is still considered the standard investigation for the detection of colorectal adenomas, but the miss rate, especially for small and flat lesions, remains unacceptably high. Chromoscopy has been shown to increase the yield for lesion detection in inflammatory bowel disease. The aim of this randomized prospective study was to determine whether a combination of chromoscopy and structure enhancement could increase the adenoma detection rate in high-risk patients.
                All patients included in the trial had a personal history of colorectal adenomas and/or a family history of colorectal cancer (but excluding genetic syndromes). They were randomized to one of two tandem colonoscopy groups, with the first pass consisting of conventional colonoscopy for both groups, followed by either chromoscopy and structure enhancement (the "study" group) or a second conventional colonoscopy (the control group) for the second-pass colonoscopy. All detected lesions was examined histopathologically after endoscopic resection or biopsy. The principal outcome parameter was the adenoma detection rate; the number, histopathology, and location of lesions was also recorded.
                A total of 292 patients were included in the study (146 patients in each group). The patients' demographic characteristics, the indications for colonoscopy, and the quality of bowel preparation were similar in the two groups. There was a significant difference between the two groups with respect to the median duration of the examination (18.9 minutes in the control group vs. 27.1 minutes for the study group, P < 0.001). Although more hyperplastic lesions were detected throughout the colon in the study group ( P = 0.033), there was no difference between the two groups in either the proportion of patients with at least one adenoma or in the total number of adenomas detected. Chromoscopy and structure enhancement diagnosed significantly more diminutive adenomas (< 5mm) in the right colon, compared with controls ( P = 0.039).
                On the basis of our results we cannot generally recommend the systematic use of chromoscopy and structure enhancement in a high-risk patient population, although the detection of small adenomas in the proximal colon was improved. Although systematic postoperative surveillance of patients with colorectal cancer has been demonstrated to improve survival, it remains unknown whether a more intensive strategy provides any significant advantage. This prospective, multicenter, randomized, controlled trial was aimed at comparing the efficacy of two different surveillance strategies in terms of both survival and recurrence resectability.
                Patients with stage II or III colorectal cancer were allocated randomly to either a simple surveillance strategy including clinical evaluation and serum carcinoembryonic antigen monitoring, or an intensive strategy in which abdominal computed tomography or ultrasonography, chest radiograph, and colonoscopy were added.
                A total of 259 patients were included: 132 were observed according to the simple strategy and 127 were observed according to the intensive strategy. Both groups were similar with respect to baseline characteristics and rate and type of tumor recurrence. After a median follow-up of 48 months, there was no difference in the probability of overall survival in the whole series (hazard ratio [HR] = 0.87; 95% CI, 0.49 to 1.54; P = .62). However, the intensive strategy was associated with higher overall survival in patients with stage II tumors (HR = 0.34; 95% CI, 0.12 to 0.98; P = .045) and in those with rectal lesions (HR = 0.09; 95% CI, 0.01 to 0.81; P = .03), mainly due to higher rate of resectability for recurrent tumors. Colonoscopy was responsible for the detection of the highest proportion (44%) of resectable tumor recurrence in the intensive arm.
                A more intensive surveillance strategy improves the prognosis of patients with stage II colorectal cancer or those with rectal tumors. Inclusion of regular performance of colonoscopy seems justified up to the fifth year of follow-up, at least. High-resolution colonoscopy with chromoscopy (HRC) is a technique designed to improve the detection of colonic neoplasias. We prospectively compared standard colonoscopy (SC) and HRC in a randomized multicenter trial.
                Patients (n = 203; age, 58 +/- 10 years; sex ratio, 1) were recruited according to the following criteria: (1) a history of either familial or personal colonic neoplasia or (2) alarm symptoms after the age of 60 years. After randomization, an SC was performed in 100 patients (resolution, < or = 410,000 pixels) and a HRC in 103 patients (Fujinon EC485ZW, 850,000 pixels). In the HRC group, each colonic segment was examined before and after spraying with indigo carmine 0.4%.
                Two hundred seventy-six polyps were detected in 198 patients. One hundred sixty of them were hyperplastic polyps, 116 were adenomas, and 2 were carcinomas. The numbers of hyperplastic polyps and purely flat adenomas were significantly higher in the HRC group than in the SC group (1.1 +/- 1.6 vs 0.5 +/- 1.4 and 0.22 +/- 0.68 vs 0.07 +/- 0.29, respectively; P = .01 and P = .04), but there was no significant difference in the total number of adenomas per patient (primary end point) detected between the HRC and the SC groups (0.6 +/- 1.0 vs 0.5 +/- 0.9, respectively).
                Although HRC improves detection of purely flat adenomas and hyperplastic polyps, the overall detection of colonic adenomas in a population at increased risk of neoplasia is not significantly improved. These findings do not support the routine use of HRC in clinical practice. To determine the harm that ensues from faecal occult blood (FOB) screening for colorectal cancer.
                150 251 people were randomly allocated either to receive biennial Haemoccult FOB tests (n =75 253) or not to be contacted (n=74 998). Study group patients returning positive tests were offered colonic investigation; 1774 underwent complete investigation of the colon.
                There was no significant difference in the stage at presentation of interval versus control group cancers. Survival in the interval cancer group was significantly prolonged compared with the control group. Sensitivity for colonoscopy or flexible sigmoidoscopy and double contrast barium enema (DCBE) was 96.7%. There were no complications of DCBE but seven (0.5%) complications of colonoscopy, of which six required surgical intervention. There were no colonoscopy related deaths. No patients without colorectal cancer died within 30 days of colonic investigation. Five patients died within 30 days of surgery for screen detected colorectal neoplasia and a further two died without having surgery. Six patients died after 30 days but within two years of surgery for screen detected benign adenomas or stage A cancers; in all cases the cause of death was not related to colorectal cancer.
                There was investigation related morbidity but no mortality and little to support overdiagnosis bias. The group returning falsely negative tests had a better outcome compared with the whole control group. There is a negative side to any screening programme but mortality reduction in this and other trials suggests that a national programme of colorectal cancer screening should be given consideration. Detection and removal of adenomas by colonoscopy is an important means for preventing cancer; however, small adenomas may be missed during colonoscopy. The narrow-band imaging (NBI) system clearly enhances the microvasculature in neoplastic lesions, making it appear as a dark complex. Therefore, the NBI system may improve the detection of colonic neoplasias. However, no randomized, controlled trials have evaluated the efficacy of a pan-colonic NBI system in adenoma detection. We conducted a randomized, controlled trial to determine the efficacy of the pancolonic NBI system in adenoma detection.
                Two hundred forty-three patients were randomized, 121 to conventional colonoscopy and 122 to pan-colonic NBI system. Demographics, indication for colonoscopy, and quality of preparation were similar between groups.
                Extubation time was not significantly different between the conventional colonoscopy and pan-colonic NBI system. The proportions of patients with at least one adenoma and those with multiple adenomas were not significantly different between groups. However, the pan-colonic NBI system significantly increased the total number of adenomas detected (P < 0.05) and the number of diminutive (<5 mm) adenomas detected (P < 0.05). The pan-colonic NBI system allowed detection of more diminutive adenomas in the distal colon than did conventional colonoscopy (P < 0.01), and more patients in the NBI group had at least one diminutive adenoma than in the control group (P < 0.05).
                The pan-colonic NBI system improves the total number of adenomas detected, including significantly more diminutive adenomas, without prolongation of extubation time. These results indicate that routine use of the NBI system for surveillance of diminutive adenomas may be recommended. Colonoscopic surveillance is a standard procedure in many patients with long standing, extensive ulcerative colitis (UC), in order to avoid death from colorectal cancer. No conclusive proof of its benefits has been presented however.
                To evaluate the association between colonoscopic surveillance and colorectal cancer mortality in patients with UC.
                A population based, nested case control study comprising 142 patients with a definite UC diagnosis, derived from a study population of 4664 patients with UC, was conducted.
                Colonoscopic surveillance in all patients with UC who had died from colorectal cancer after 1975 was compared with that in controls matched for age, sex, extent, and duration of the disease. Information on colonoscopic surveillance was obtained from the medical records.
                Two of 40 patients with UC and 18 of 102 controls had undergone at least one surveillance colonoscopy (relative risk (RR) 0.29, 95% confidence interval 0.06 to 1.31). Twelve controls but only one patient with UC had undergone two or more surveillance colonoscopies (RR 0.22, 95% confidence interval 0.03 to 1.74), indicating a protective dose response relation.
                Colonoscopic surveillance may be associated with a decreased risk of death from colorectal cancer in patients with long standing UC. To control the increased risk of colorectal carcinoma in patients with long-standing ulcerative colitis, surveillance colonoscopy is widely recommended.
                To assess the role of colonoscopic surveillance in affecting colorectal carcinoma-related mortality, an outcome analysis was performed.
                Among the total of 41 patients who developed carcinoma associated with ulcerative colitis, 19 patients were under colonoscopic surveillance and 22 patients were not. Carcinoma was detected at a significantly earlier Dukes' stage in the surveillance group (P = 0.039). Four patients in the surveillance group died, compared with 11 patients in the no-surveillance group. The 5-year survival rate was 77.2% for the surveillance group and 36.3% for the no-surveillance group (P = 0.026).
                These results suggest that colonoscopic surveillance reduces colorectal carcinoma-related mortality by allowing the detection of carcinoma at an earlier Dukes' stage.
There appears to be strong evidence that chromoscopy enhances the detection of neoplasia in the colon and rectum. Patients with neoplastic polyps, particularly those with multiple polyps, are at increased risk of developing colorectal cancer. Such lesions, which presumably would be missed with conventional colonoscopy, could contribute to the interval cancer numbers on any surveillance programme.