Fecal Occult Blood Tests in Colorectal Cancer Screening: Systematic Review and Meta-analysis of Traditional and New-generation Fecal Immunochemical Tests.

BACKGROUND/AIM: Noninvasive fecal occult blood tests (FOBTs) are recommended by current guidelines for colorectal cancer (CRC) screening. Our aim was to assess the diagnostic performance of traditional guaiac-based FOBTs (gFOBT) and new-generation immunochemical FOBTs (iFOBT) in CRC screening by carrying out a systematic review and meta-analysis.

PATIENTS AND METHODS

PubMed, Embase, Cochrane Library, and Web of Science were searched for eligible articles published before February 17, 2020. Three independent investigators conducted study assessment and data extraction. Diagnosis-related indicators for use of FOBTs in the detection of CRC (as the endpoint) in a screening setting were summarized, and further stratified by the type of FOBT (gFOBT vs. iFOBT). STATA software was used to conduct the meta-analysis. Pooled sensitivities and specificities were calculated using a random-effects model. Hierarchical summary receiver operating characteristic curves were plotted and area under the curves (AUC) were calculated.

RESULTS

The electronic search identified 573 records after duplicates were removed, of which 75 full-text articles were assessed for eligibility. Finally, a total of 31 studies were eligible for the meta-analysis. In the ROC comparison test, there was a statistically significant difference in the performance of gFOBT and iFOBT tests, with AUC=0.77 (95% confidence intervaI=0.75-0.79) and AUC=0.87 (95% confidence intervaI=0.85-0.88), respectively (p=0.0017). In formal meta-regression, test brand did not prove to be a significant study-level covariate that would explain the observed heterogeneity between the studies.

CONCLUSION

New-generation iFOBTs were found to have a significantly higher diagnostic performance as compared with gFOBTs, advocating the use of only fecal immunochemical tests in all newly implemented CRC screening programs.