Musil D, Tillich J
IInd Medical Clinic of University Hospital, Olomouc, Czech Republic.
Acta Univ Palacki Olomuc Fac Med. 1999;142:119-21.
There is a high prevalence and incidence of colorectal cancer in industrial countries. It is the commonest cancer in women after breast cancer and in men after prostate and lung cancer and one of the most common causes of death from malignant disease. The cause of colorectal cancer is unknown, thus primary-prevention programs could not be elaborated and the only occasion to reduce mortality is the use of screening to detect this cancer early. Faecal occult blood test (FOBT) was chosen for screening. Large population based trials included thousands of inhabitants of the United States and Europe to demonstrate: 1. Screening with FOBT Hemoccult II reduced mortality from colorectal cancer. 2. In the screening group the incidence of advanced stages of colorectal cancer decreased (Dukes' D stage). 3. The ideal balance between sensitivity and specificity revealed HemeSelect (immunodiagnosis of human haemoglobine) and combined test (Hemoccult II Sensa + HemeSelect). These two screening tests for colorectal cancer have not been verified by large population trials. 4. More sensitive guaiac tests decrease their own specificity and also lead to increase rate of expensive colon examinations. 5. The high-risk population for colorectal cancer ought to be submitted to screening. The problem is the detection of this group. 6. Patients' compliance to screening differs in various trials, but the percentage of patients undergoing FOBT evaluation decreases as the number of screenings increases. Therefore faecal occult blood test could be recommended for national programs of the screening for colorectal cancer.
在工业化国家,结直肠癌的患病率和发病率都很高。它是女性继乳腺癌之后、男性继前列腺癌和肺癌之后最常见的癌症,也是恶性疾病最常见的死亡原因之一。结直肠癌的病因不明,因此无法制定一级预防方案,降低死亡率的唯一机会是通过筛查尽早发现这种癌症。粪便潜血试验(FOBT)被选用于筛查。基于大量人群的试验纳入了数千名美国和欧洲居民,以证明:1. 使用Hemoccult II进行粪便潜血试验筛查可降低结直肠癌死亡率。2. 在筛查组中,结直肠癌晚期(杜克D期)的发病率有所下降。3. HemeSelect(人血红蛋白免疫诊断法)和联合试验(Hemoccult II Sensa + HemeSelect)在敏感性和特异性之间达到了理想平衡。这两种结直肠癌筛查试验尚未通过大量人群试验验证。4. 更敏感的愈创木脂试验会降低其自身的特异性,还会导致昂贵的结肠镜检查率增加。5. 结直肠癌高危人群应接受筛查。问题在于如何检测出这一群体。6. 在不同试验中,患者对筛查的依从性有所不同,但随着筛查次数的增加,接受粪便潜血试验评估的患者比例会下降。因此,粪便潜血试验可推荐用于国家结直肠癌筛查项目。