临床上结肠镜检查手术过程中，一根前头装备摄像头的软管顺着患者口腔食管一直插入直肠中，然后将软管滑行延伸至患者结肠部位。在进行结肠镜检查时，尚未发生癌变的腺瘤性息肉是结肠部位最常见的异样物质。如果在做结肠镜检查手术时不及时将它切除的话，腺瘤性息肉有很有可能发生癌变，导致结肠癌的发生。
美国癌症研究院统计显示：2011年，美国有100,000对例新增结肠癌病例，40,000多例新增直肠癌病例，有49,000名结肠/直肠癌患者死亡。来自美国Memorial Sloan-Kettering癌症中心的研究人员早些时候完成的一项研究证实在进行结肠镜检查的时候，切除癌前期息肉能起到预防结肠癌发展的作用。2月23日，N Engl J Med上刊出的一篇研究论文指出：在结肠镜检查时切除癌前期息肉能使患者因结肠癌死亡的风险减半。该研究也是由美国Memorial Sloan-Kettering癌症中心领导，研究人员包括内视镜专家、病理学家、放射学家和流行病学家等。
该项研究的主要领导者Memorial Sloan-Kettering癌症中心的生物统计学家--Ann G. Zauber博士称：这项研究证实了我们能从切除结肠部位腺瘤性息肉手术中长期受益，我们完全可以利用结肠镜检查手术筛查50岁以上的群体是否罹患结肠癌。
Zauber等人调查研究了NPS数据库中患者病例信息，NPS（美国息肉研究）收录了1980至1990年间，美国各地患者接受结肠镜检查的相关信息。工作者收集了2,602名在结肠镜检查手术中切除腺瘤性息肉的患者信息，并进行随访，其中最长的追访研究长达23年。结果发现在15.8年（中位数）以后，有1,246名患者因为罹患其他疾病病去世，因罹患结肠癌去世的人数只有12名。
研究人员还发现不管癌症患者之前长得是不是已经癌变或是未发生癌变的腺瘤性息肉，在接受结肠镜检查时切除息肉后的头十年里，结肠癌患者死亡率都很低。
该研究另一主要领导者--消化系统癌症专家Winawer教授认为结肠镜检查术应该作为美国结肠癌筛查指南中的关键部分，要在全球范围内进行推广。（生物谷Bioon.com）
doi:10.1056/NEJMoa1100370
PMC:
PMID:
Colonoscopic Polypectomy and Long-Term Prevention of Colorectal-Cancer Deaths
Ann G. Zauber, Ph.D., Sidney J. Winawer, M.D., Michael J. O'Brien, M.D., M.P.H., Iris Lansdorp-Vogelaar, Ph.D., Marjolein van Ballegooijen, M.D., Ph.D.,et al.
Background
In the National Polyp Study (NPS), colorectal cancer was prevented by colonoscopic removal of adenomatous polyps. We evaluated the long-term effect of colonoscopic polypectomy in a study on mortality from colorectal cancer.
Methods
We included in this analysis all patients prospectively referred for initial colonoscopy (between 1980 and 1990) at NPS clinical centers who had polyps (adenomas and nonadenomas). The National Death Index was used to identify deaths and to determine the cause of death; follow-up time was as long as 23 years. Mortality from colorectal cancer among patients with adenomas removed was compared with the expected incidence-based mortality from colorectal cancer in the general population, as estimated from the Surveillance Epidemiology and End Results (SEER) Program, and with the observed mortality from colorectal cancer among patients with nonadenomatous polyps (internal control group).
Results
Among 2602 patients who had adenomas removed during participation in the study, after a median of 15.8 years, 1246 patients had died from any cause and 12 had died from colorectal cancer. Given an estimated 25.4 expected deaths from colorectal cancer in the general population, the standardized incidence-based mortality ratio was 0.47 (95% confidence interval [CI], 0.26 to 0.80) with colonoscopic polypectomy, suggesting a 53% reduction in mortality. Mortality from colorectal cancer was similar among patients with adenomas and those with nonadenomatous polyps during the first 10 years after polypectomy (relative risk, 1.2; 95% CI, 0.1 to 10.6).
Conclusions
These findings support the hypothesis that colonoscopic removal of adenomatous polyps prevents death from colorectal cancer. (Funded by the National Cancer Institute and others.)
