Barclay Robert L, Vicari Joseph J, Doughty Andrea S, Johanson John F, Greenlaw Roger L
Rockford Gastroenterology Associates, IL 61107, USA.
N Engl J Med. 2006 Dec 14;355(24):2533-41. doi: 10.1056/NEJMoa055498.
Colonoscopy is commonly used to screen for neoplasia. To assess the performance of screening colonoscopy in everyday practice, we conducted a study of the rates of detection of adenomas and the amount of time taken to withdraw the colonoscope among endoscopists in a large community-based practice.
During a 15-month period, 12 experienced gastroenterologists performed 7882 colonoscopies, of which 2053 were screening examinations in subjects who had not previously undergone colonoscopy. We recorded the numbers, sizes, and histologic features of the neoplastic lesions detected during screening, as well as the duration of insertion and of withdrawal of the colonoscope during the procedure. We compared rates of detection of neoplastic lesions among gastroenterologists who had mean colonoscopic withdrawal times of less than 6 minutes with the rates of those who had mean withdrawal times of 6 minutes or more. According to experts, 6 minutes is the minimum length of time to allow adequate inspection during instrument withdrawal.
Neoplastic lesions (mostly adenomatous polyps) were detected in 23.5% of screened subjects. There were large differences among gastroenterologists in the rates of detection of adenomas (range of the mean number of lesions per subject screened, 0.10 to 1.05; range of the percentage of subjects with adenomas, 9.4 to 32.7%) and in their times of withdrawal of the colonoscope from the cecum to the anus (range, 3.1 to 16.8 minutes for procedures during which no polyps were removed). As compared with colonoscopists with mean withdrawal times of less than 6 minutes, those with mean withdrawal times of 6 minutes or more had higher rates of detection of any neoplasia (28.3% vs. 11.8%, P<0.001) and of advanced neoplasia (6.4% vs. 2.6%, P=0.005).
In this large community-based gastroenterology practice, we observed greater rates of detection of adenomas among endoscopists who had longer mean times for withdrawal of the colonoscope. The effect of variation in withdrawal times on lesion detection and the prevention of colorectal cancer in the context of widespread colonoscopic screening is not known. Ours was a preliminary study, so the generalizability and implications for clinical practice need to be determined by future studies.
结肠镜检查常用于筛查肿瘤。为评估日常实践中筛查结肠镜检查的效果，我们对一个大型社区医疗机构中内镜医师的腺瘤检出率及结肠镜退镜时间进行了研究。
在15个月期间，12名经验丰富的胃肠病学家进行了7882例结肠镜检查，其中2053例是对之前未做过结肠镜检查的受试者进行的筛查。我们记录了筛查期间发现的肿瘤性病变的数量、大小和组织学特征，以及检查过程中结肠镜插入和退镜的时间。我们比较了平均结肠镜退镜时间少于6分钟的胃肠病学家与平均退镜时间为6分钟或更长的胃肠病学家的肿瘤性病变检出率。据专家称，6分钟是退镜时进行充分检查的最短时间。
23.5%的筛查受试者发现了肿瘤性病变（大多为腺瘤性息肉）。内镜医师之间腺瘤检出率差异很大（每名筛查受试者的平均病变数范围为0.10至1.05；有腺瘤受试者的百分比范围为9.4%至32.7%），且从盲肠到肛门的结肠镜退镜时间也不同（未切除息肉的检查退镜时间范围为3.1至16.8分钟）。与平均退镜时间少于6分钟的结肠镜检查医师相比，平均退镜时间为6分钟或更长的医师任何肿瘤的检出率更高（28.3%对11.8%，P<0.001），高级别肿瘤的检出率也更高（6.4%对2.6%，P=0.005）。
在这个大型社区胃肠病学实践中，我们观察到结肠镜退镜平均时间较长的内镜医师腺瘤检出率更高。在广泛的结肠镜筛查背景下，退镜时间变化对病变检测和预防结直肠癌的影响尚不清楚。我们的研究是一项初步研究，因此其普遍性及对临床实践的意义需由未来研究确定。
