Rex D K, Mark D, Clarke B, Lappas J C, Lehman G A
Department of Medicine, Indiana University School of Medicine, Indianapolis, USA.
Gastrointest Endosc. 1995 Aug;42(2):132-8. doi: 10.1016/s0016-5107(95)70069-2.
One hundred forty-nine patients aged 40 years or more with symptoms suggestive of colonic disease but without evidence of gastrointestinal bleeding (absence of hematochezia, normal serum levels of hemoglobin, and at least one test negative for fecal occult blood) were randomized to undergo either initial colonoscopy or initial flexible sigmoidoscopy plus air-contrast barium enema. Patients with incomplete initial colonoscopy and certain patients with polyps seen on flexible sigmoidoscopy plus barium enema underwent the alternative procedure (barium enema or colonoscopy). The main results were as follows: First, the overall prevalence of cancer in the study was very low (0.67%). Second, initial flexible sigmoidoscopy plus barium enema detected more patients with diverticulosis than did initial colonoscopy (46% versus 31%; p = .01). Initial colonoscopy detected more persons with adenomas (p = .06) than did initial flexible sigmoidoscopy plus barium enema. Patients undergoing initial flexible sigmoidoscopy plus barium enema require the alternative procedure (24%) than were patients undergoing initial colonoscopy (6%; p = .002). Third, sensitivity analyses suggested that for most areas in the United States, initial colonoscopy would be more cost-effective for the outcomes of detection of adenomas and detection of large adenomas, although very few patients in the study had large adenomas. We conclude that the prevalence of colorectal cancer in persons with colonic symptoms but no evidence of bleeding is low and is comparable with the prevalence in an asymptomatic population. Cost-effective selection of imaging strategies in this population can be based on demographic factors such as age and sex, which are better predictors of the presence of adenomas than are symptoms.
149名年龄在40岁及以上、有结肠疾病症状但无胃肠道出血证据（无便血、血红蛋白血清水平正常且至少一项粪便潜血试验阴性）的患者被随机分为两组，一组接受初始结肠镜检查，另一组接受初始乙状结肠镜检查加气钡双重造影灌肠。初始结肠镜检查不完全的患者以及在乙状结肠镜检查加钡灌肠中发现息肉的某些患者接受了替代检查（钡灌肠或结肠镜检查）。主要结果如下：第一，研究中癌症的总体患病率非常低（0.67%）。第二，初始乙状结肠镜检查加钡灌肠比初始结肠镜检查发现更多憩室病患者（46%对31%；p = 0.01）。初始结肠镜检查比初始乙状结肠镜检查加钡灌肠发现更多腺瘤患者（p = 0.06）。接受初始乙状结肠镜检查加钡灌肠的患者需要接受替代检查的比例（24%）高于接受初始结肠镜检查的患者（6%；p = 0.002）。第三，敏感性分析表明，对于美国的大多数地区，初始结肠镜检查对于腺瘤检测和大腺瘤检测的结果而言更具成本效益，尽管研究中很少有患者患有大腺瘤。我们得出结论，有结肠症状但无出血证据的人群中结直肠癌的患病率较低，与无症状人群的患病率相当。在这一人群中具有成本效益的成像策略选择可基于年龄和性别等人口统计学因素，这些因素比症状更能预测腺瘤的存在。
