Mandel J S, Bond J H, Church T R, Snover D C, Bradley G M, Schuman L M, Ederer F
Division of Environmental and Occupational Health, University of Minnesota, Minneapolis 55455.
N Engl J Med. 1993 May 13;328(19):1365-71. doi: 10.1056/NEJM199305133281901.
Although tests for occult blood in the feces are widely used to screen for colorectal cancers, there is no conclusive evidence that they reduce mortality from this cause. We evaluated a fecal occult-blood test in a randomized trial and documented its effectiveness.
We randomly assigned 46,551 participants 50 to 80 years of age to screening for colorectal cancer once a year, to screening every two years, or to a control group. Participants who were screened submitted six guaiac-impregnated paper slides with two smears from each of three consecutive stools. About 83 percent of the slides were rehydrated. Participants who tested positive underwent a diagnostic evaluation that included colonoscopy. Vital status was ascertained for all study participants during 13 years of follow-up. A committee determined causes of death. A single pathologist determined the stage of each tissue specimen. Differences in mortality from colorectal cancer, the primary study end point, were monitored with the sequential log-rank statistic.
The 13-year cumulative mortality per 1000 from colorectal cancer was 5.88 in the annually screened group (95 percent confidence interval, 4.61 to 7.15), 8.33 in the biennially screened group (95 percent confidence interval, 6.82 to 9.84), and 8.83 in the control group (95 percent confidence interval, 7.26 to 10.40). The rate in the annually screened group, but not in the biennially screened group, was significantly lower than that in the control group. Reduced mortality in the annually screened group was accompanied by improved survival in those with colorectal cancer and a shift to detection at an earlier stage of cancer.
Annual fecal occult-blood testing with rehydration of the samples decreased the 13-year cumulative mortality from colorectal cancer by 33 percent.
尽管粪便潜血检测被广泛用于筛查结直肠癌，但尚无确凿证据表明其能降低因该病因导致的死亡率。我们在一项随机试验中评估了一种粪便潜血检测，并记录了其有效性。
我们将46551名年龄在50至80岁的参与者随机分为三组，分别为每年进行一次结直肠癌筛查组、每两年进行一次筛查组和对照组。接受筛查的参与者提交六张愈创木脂浸渍的载玻片，每张载玻片上有来自连续三次粪便中每次两次涂片。约83%的载玻片进行了复水。检测呈阳性的参与者接受包括结肠镜检查在内的诊断评估。在13年的随访期间确定了所有研究参与者的生命状态。一个委员会确定死因。由一名病理学家确定每个组织标本的分期。使用序贯对数秩统计量监测作为主要研究终点的结直肠癌死亡率差异。
每1000人中结直肠癌的13年累积死亡率在每年筛查组为5.88（95%置信区间，4.61至7.15），在每两年筛查组为8.33（95%置信区间，6.82至9.84），在对照组为8.83（95%置信区间，7.26至10.40）。每年筛查组的死亡率显著低于对照组，但每两年筛查组并非如此。每年筛查组死亡率的降低伴随着结直肠癌患者生存率的提高以及癌症检测阶段的提前。结论：每年进行粪便潜血检测并对样本进行复水可使结直肠癌的13年累积死亡率降低33%。
