Background

Prior studies have shown that individuals with fecal hemoglobin (f-Hb) concentrations just below the positivity cut-off have an increased colorectal cancer (CRC) risk compared to those with no or low f-Hb. Understanding the dose-response association between f-Hb in prior screening round and the detection of colorectal neoplasia is crucial for tailoring risk-based screening recommendations.

Methods

We searched the literature to identify studies reporting the association between f-Hb in prior screening round and colorectal neoplasia detection in an average-risk population. Analysis involved a two-stage approach using log-log regression models to assess dose-response relationships across studies, with effect sizes pooled using a random effects model. Heterogeneity was assessed by excluding individual studies in sensitivity analyses. Subgroup analyses examined variations in effects by outcome definitions and detection methods.

Results

This systematic review and meta-analysis included 13 studies with 4,493,223 individuals. All studies demonstrated a positive association between f-Hb in prior screenings and colorectal neoplasia detection. Pooled analysis revealed that individuals with f-Hb concentrations of 5, 10, 20, and 40 μg/g had a 3-, 5-, 8-, and 13-fold higher risk of colorectal neoplasia, respectively, compared to individuals with 0 μg/g. Although significant heterogeneity (I² = 97.5%, p < 0.001) was observed, sensitivity analyses confirmed the consistency of findings. Subgroup analyses indicated that f-Hb concentrations from previous negative tests were especially predictive of advanced neoplasia in subsequent screenings.

Conclusion

Our findings suggest that the risk of detecting colorectal neoplasia increases with prior f-Hb concentrations in negative tests, supporting the development of risk-stratified screening strategies based on these concentrations.

中文翻译：

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结直肠肿瘤既往阴性筛查和检测中的粪便血红蛋白水平：剂量反应荟萃分析

 背景

先前的研究表明，与没有 f-Hb 或低 f-Hb 的个体相比，粪便血红蛋白 （f-Hb） 浓度略低于阳性临界值的个体患结直肠癌 （CRC） 的风险增加。了解先前筛查轮次中 f-Hb 与结直肠肿瘤检测之间的剂量反应关联对于定制基于风险的筛查建议至关重要。

 方法

我们检索了文献，以确定报告了既往筛查轮次中 f-Hb 与平均风险人群中结直肠瘤变检测之间关联的研究。分析涉及使用对数-对数回归模型的两阶段方法来评估研究之间的剂量-反应关系，并使用随机效应模型合并效应大小。通过在敏感性分析中排除个体研究来评估异质性。亚组分析按结局定义和检测方法检查了效应的变化。

 结果

本系统评价和荟萃分析包括 13 项研究，涉及 4,493,223 人。所有研究表明，既往筛查中的 f-Hb 与结直肠瘤检测呈正相关。汇总分析显示，与 0 μg/g 的个体相比，f-Hb 浓度为 5、10、20 和 40 μg/g 的个体患结直肠瘤变的风险分别高 3 倍、5 倍、8 倍和 13 倍。尽管观察到显著的异质性 （I² = 97.5%，p < 0.001），但敏感性分析证实了结果的一致性。亚组分析表明，在随后的筛查中，先前阴性检测的 f-Hb 浓度特别能预测晚期肿瘤。

 结论

我们的研究结果表明，检测结直肠瘤变的风险随着阴性检测中 f-Hb 浓度的增加而增加，这支持根据这些浓度开发风险分层筛查策略。