Winawer S J, Flehinger B J, Schottenfeld D, Miller D G
Gastroenterology and Nutrition Service, Memorial Sloan-Kettering Cancer Center, New York, N.Y. 10021.
J Natl Cancer Inst. 1993 Aug 18;85(16):1311-8. doi: 10.1093/jnci/85.16.1311.
The high incidence of and mortality from colorectal cancer (160,000 new cases and 60,000 deaths in the United States each year) are compelling public health concerns. Following the evolution of effective surgery for this disease since the 1960s, the focus has been on improving methods of detection and integrating them into effective screening programs.
This was the first study to evaluate the effectiveness, in a setting of comprehensive medical examinations, of using the fecal occult blood test in conjunction with sigmoidoscopy, rather than sigmoidoscopy alone, to screen for colorectal cancer. Our end points were extent of compliance with fecal occult blood test and sigmoidoscopy, numbers of cancers detected, and mortality rate.
From 1975 through 1979, a total of 21,756 patients (aged 40 and older) who presented at the Preventive Medicine Institute-Strang Clinic for routine medical examinations were enrolled by calendar period into study and control groups. Study patients were offered annually both rigid sigmoidoscopy examinations and fecal occult blood tests requiring two stool specimens per day for 3 days, while control patients were offered only annual sigmoidoscopy. The majority of fecal occult blood test cards were not rehydrated before assay. Patients with positive tests were referred for double-contrast barium enema and colonoscopy. Two distinct trials were carried out. Trial I was primarily a demonstration of feasibility of using the fecal occult blood test as a supplemental screening method. Of the 9277 participants, 7168 (77%) were assigned to the study group and offered the fecal occult blood test. In trial II, approximately half of the 12,479 patients were assigned to each group. Patients in both trials had follow-up through 1984.
Compliance with the fecal occult blood test was initially high in both trials, but diminished such that only 56% of study patients in trial I and 20% of those in trial II returned for second tests. On the initial (prevalence) screen, a substantial number of early-stage cancers were detected by the fecal occult blood test, primarily in trial II. In trial II, survival probability was significantly greater (P < .001) in the study group than in the controls (70% versus 48%), and colorectal cancer mortality was lower (0.36 versus 0.63) with borderline significance (P = .053, one-sided).
The screening of average-risk individuals (aged 50 and older) for colorectal cancer through use of the fecal occult blood test in conjunction with sigmoidoscopy can increase the likelihood of early detection of this disease. This practice, coupled with prompt diagnostic work-up following positive tests, will result in treatment of earlier stage cancers and increased survival after treatment.
结直肠癌的高发病率和高死亡率（美国每年有16万新发病例和6万例死亡）是令人担忧的公共卫生问题。自20世纪60年代以来，随着针对该疾病的有效手术方法的发展，重点已转向改进检测方法并将其纳入有效的筛查计划。
这是第一项评估在综合体检中，联合使用粪便潜血试验和乙状结肠镜检查而非单独使用乙状结肠镜检查来筛查结直肠癌的有效性的研究。我们的终点指标包括粪便潜血试验和乙状结肠镜检查的依从程度、检测出的癌症数量以及死亡率。
从1975年至1979年，共有21756名40岁及以上的患者到预防医学研究所 - 斯特朗诊所进行常规体检，按日历时间段将他们纳入研究组和对照组。研究组患者每年接受硬性乙状结肠镜检查和粪便潜血试验，粪便潜血试验要求每天采集两份粪便标本，共采集3天，而对照组患者仅每年接受乙状结肠镜检查。大多数粪便潜血试验卡检测前未复水。检测呈阳性的患者被转诊进行双重对比钡灌肠和结肠镜检查。进行了两项不同的试验。试验I主要是证明使用粪便潜血试验作为补充筛查方法的可行性。在9277名参与者中，7168名（77%）被分配到研究组并接受粪便潜血试验。在试验II中，12479名患者中约一半被分配到每组。两项试验中的患者均随访至1984年。
两项试验中粪便潜血试验的初始依从性都很高，但随后下降，以至于试验I中只有56%的研究组患者和试验II中20%的患者返回进行第二次检测。在初始（患病率）筛查中，粪便潜血试验检测出大量早期癌症，主要在试验II中。在试验II中，研究组的生存概率显著高于对照组（P <.001）（70%对48%），结直肠癌死亡率较低（0.36对0.63），具有临界显著性（P =.053，单侧）。
通过联合使用粪便潜血试验和乙状结肠镜检查对平均风险个体（50岁及以上）进行结直肠癌筛查，可以增加该疾病早期检测的可能性。这种做法，再加上检测呈阳性后及时进行诊断检查，将导致早期癌症得到治疗并提高治疗后的生存率。
