1] Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, Germany [2] German Cancer Consortium (DKTK), Heidelberg, Germany.
Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Heidelberg, Germany.
Am J Gastroenterol. 2014 Mar;109(3):427-35. doi: 10.1038/ajg.2013.424. Epub 2013 Dec 17.
Randomized trials have shown that annual or biannual screening by guaiac-based fecal occult blood tests (gFOBTs) reduces colorectal cancer (CRC) mortality. Few clinical studies have evaluated diagnostic performance of gFOBT through validation by colonoscopy in all participants. We aimed for a comprehensive evaluation of diagnostic performance of gFOBT by age and sex under routine screening conditions.
Our analysis is based on 20,884 colonoscopies following up a positive gFOBT and 182,956 primary screening colonoscopies documented in a state-wide quality assurance program in Bavaria, Germany, in 2007-2009. Positive likelihood ratios (LR+), which represent an integrative measure of diagnostic performance, were derived, by age groups (55-59, 60-64, 65-69, 70-74 years) and sex, from a joint and comparative analysis of prevalences of colorectal neoplasms in both groups.
Overall LR+ (95% confidence intervals) were 1.11 (1.06-1.15), 1.80 (1.72-1.88), and 5.04 (4.64-5.47) for non-advanced adenoma, advanced adenoma, and cancer, respectively. Assuming a specificity of gFOBT of 95.2%, as recently observed in a German study among 2,235 participants of screening colonoscopy, these LR+ would translate to sensitivities of 5.3%, 8.6%, and 24.2% for the three outcomes, respectively. Diagnostic performance was similarly poor among women and men and across age groups.
The performance of gFOBT under routine screening conditions is even worse than previously estimated from clinical studies. In routine screening application, gFOBTs are expected to miss more than 9 out of 10 advanced adenomas and 3 out of 4 cancers. These results underline the need and the potential for better noninvasive CRC screening tests.
随机试验表明，每年或每两年进行一次基于愈创木脂的粪便隐血试验（gFOBT）筛查可以降低结直肠癌（CRC）的死亡率。很少有临床研究通过对所有参与者进行结肠镜检查来验证 gFOBT 的诊断性能。我们旨在根据年龄和性别，在常规筛查条件下全面评估 gFOBT 的诊断性能。
我们的分析基于 2007 年至 2009 年在德国巴伐利亚州进行的一项全州质量保证计划中记录的 20884 例阳性 gFOBT 随访结肠镜检查和 182956 例原发性筛查结肠镜检查。阳性似然比（LR+）是通过对两组中结直肠肿瘤患病率的联合和比较分析，按年龄组（55-59 岁、60-64 岁、65-69 岁、70-74 岁）和性别得出的，是诊断性能的综合衡量指标。
非高级腺瘤、高级腺瘤和癌症的总体 LR+（95%置信区间）分别为 1.11（1.06-1.15）、1.80（1.72-1.88）和 5.04（4.64-5.47）。假设 gFOBT 的特异性为 95.2%，如最近在一项德国研究中对 2235 名筛查结肠镜检查参与者观察到的那样，这些 LR+将分别转化为三种结果的敏感性为 5.3%、8.6%和 24.2%。女性和男性以及各年龄组的诊断性能均较差。
在常规筛查条件下，gFOBT 的性能甚至比以前从临床研究中估计的还要差。在常规筛查应用中，gFOBT 预计会错过超过 10 个中的 9 个高级腺瘤和 4 个中的 3 个癌症。这些结果强调了需要并有可能开发出更好的非侵入性 CRC 筛查测试。
