Mandel J S, Church T R, Bond J H, Ederer F, Geisser M S, Mongin S J, Snover D C, Schuman L M
Exponent, Menlo Park, Calif 94025, USA.
N Engl J Med. 2000 Nov 30;343(22):1603-7. doi: 10.1056/NEJM200011303432203.
Both annual testing for fecal occult blood and biennial testing significantly reduce mortality from colorectal cancer. However, the effect of screening on the incidence of colorectal cancer remains uncertain, despite the diagnosis and removal of precancerous lesions in many persons who undergo screening.
We followed the participants in the Minnesota Colon Cancer Control Study for 18 years. A total of 46,551 people, most of whom were 50 to 80 years old, were enrolled between 1975 and 1978 and randomly assigned to annual screening, biennial screening, or usual care (the control group). Those assigned to the screening groups were asked to prepare and submit two samples from each of three consecutive stools for guaiac-based testing. Those with at least one positive slide in the set of six were offered a diagnostic examination that included colonoscopy. Screening was conducted between 1976 and 1982 and again between 1986 and 1992. Study participants have been followed with respect to newly diagnosed cases of colorectal cancer and deaths. Follow-up has been more than 90 percent complete.
During the 18-year follow-up period, we identified 1359 new cases of colorectal cancer: 417 in the annual-screening group, 435 in the biennial-screening group, and 507 in the control group. The cumulative incidence ratios for colorectal cancer in the screening groups as compared with the control group were 0.80 (95 percent confidence interval, 0.70 to 0.90) and 0.83 (95 percent confidence interval, 0.73 to 0.94) for the annual-screening and biennial-screening groups, respectively. For both screening groups, the number of positive slides was associated with the positive predictive value both for colorectal cancer and for adenomatous polyps at least 1 cm in diameter.
The use of either annual or biennial fecal occult-blood testing significantly reduces the incidence of colorectal cancer.
每年进行粪便潜血检测和每两年进行一次检测均能显著降低结直肠癌死亡率。然而，尽管许多接受筛查的人被诊断并切除了癌前病变，但筛查对结直肠癌发病率的影响仍不确定。
我们对明尼苏达结肠癌控制研究的参与者进行了18年的随访。1975年至1978年间，共招募了46551人，其中大多数年龄在50至80岁之间，他们被随机分配至每年筛查组、每两年筛查组或常规护理组（对照组）。被分配到筛查组的人被要求从连续三次粪便中每次各准备并提交两份样本进行愈创木脂检测。在六份样本中至少有一份呈阳性的人会接受包括结肠镜检查在内的诊断性检查。筛查在1976年至1982年期间进行了一次，在1986年至1992年期间又进行了一次。对研究参与者的结直肠癌新发病例和死亡情况进行了随访。随访的完成率超过90%。
在18年的随访期内，我们共确诊了1359例结直肠癌新病例：每年筛查组417例，每两年筛查组435例，对照组507例。每年筛查组和每两年筛查组与对照组相比，结直肠癌的累积发病率分别为0.80（95%置信区间为0.70至0.90）和0.83（95%置信区间为0.73至0.94）。对于两个筛查组，阳性样本数量与结直肠癌以及直径至少为1厘米的腺瘤性息肉的阳性预测值均相关。
每年或每两年进行粪便潜血检测均可显著降低结直肠癌的发病率。
