Impact of Preanalytical Factors on Fecal Immunochemical Tests: Need for New Strategies in Comparison of Methods. Issue 3 (July 2015)

• Record Type: Journal Article
• Authors: Rubeca, Tiziana; Cellai, Filippo; Confortini, Massimo; Fraser, Callum G.; Rapi, Stefano
• Is Part Of: International journal of biological markers. Volume 30:Issue 3(2015)
• Page Start: 269
• Page End: 274
• Publication Date: 2015-07
• Subjects: Colorectal cancer screening -- Fecal sampling -- Fecal test comparison -- Fecal test standardization -- FIT -- Quantitative fecal immunochemical test for hemoglobin; Cell receptors -- Periodicals; Histochemistry -- Periodicals; Tumor markers -- Periodicals; Tumor antigens -- Periodicals; 616.99407582
• DOI: 10.5301/jbm.5000150
• Languages: English
• ISSNs: 0393-6155

Abstract

Background: Harmonization of fecal immunochemical tests for hemoglobin (FIT-Hb) is crucial to compare clinical outcomes in screening programs. The lack of reference materials and standard procedures does not allow the use of usual protocols to compare methods. We propose 2 protocols, based on artificial biological samples (ABS), to discriminate preanalytical and analytical variation and investigate clinical performances. The protocols were used to compare 2 FIT systems available on European markets: the OC-Sensor Diana (Eiken, Tokyo, Japan) and HM-JACKarc (Kyowa-Medex, Tokyo, Japan). Methods: ABS were obtained adding Hb to Hb-free feces. In the first procedure, 35 ABS were collected for each collection device and analyzed on both systems. In the second, 188 ABS (106 positive and 82 negative) were ­collected and tested on the specific systems. Passing-Bablock (PB), Pearson's correlation coefficients (R) and Bland-Altman difference analysis were used to compare data. Results: PB, R and mean standard errors for Bland-Altman analysis (Diana vs. Arc) results were 0.93x-0.56: R = 0.97 and 19%; and 1.09x + 5.60: R = 0.96 and −18%; for Diana and Arc devices, respectively. No correlations and no difference in positive/negative assessment were observed with the second protocol. Conclusions: A good correlation was observed in comparing data generated using collection devices on the 2 systems. Manufacturers have developed different sample collection procedures for feces: therefore, data from different systems cannot easily be compared. Adoption of protocols to discriminate preanalytical and analytical variation would be a significant contribution to harmonization of FIT, facilitating data comparison and information acquisition for sample collection strategy and effect of buffers on systems.