Lab Med Qual Assur.  2021 Dec;43(4):190-198. 10.15263/jlmqa.2021.43.4.190.

Evaluation of the Cut-Off Value of Fecal Immunochemical Test for Colorectal Cancer Screening during Health Checkups

• Park HR
• Nah EH
• Lee JS
• Cho S

• KMID: 2524187
• DOI: http://doi.org/10.15263/jlmqa.2021.43.4.190

Abstract

Background
The fecal immunochemical test (FIT) is recommended as the first choice for mass colorectal cancer (CRC) screening in the community. The cut-off value can be adjusted according to the target population and colonoscopy resources. We aimed to compare and determine the optimal cut-off value for CRC screening to strike a balance between FIT performance and colonoscopy burden.
Methods
This cross-sectional retrospective study consecutively selected subjects who underwent health checkups including FIT and colonoscopy at 16 health-promotion centers in Korea between 2018 and 2019. FIT was performed using an OC-SENSOR PLEDIA (Eiken Chemical Co., Japan). We assessed the test performance in detecting CRC and measured the burden of colonoscopy with different cut-off values of 22 (FIT 22) ng/mL, 50 (FIT 50) ng/mL, and 100 (FIT 100) ng/mL.
Results
Among the 90,323 participants, CRC was found in 485 patients (0.54%). From FIT 22 and, FIT 50 to FIT 100, the positivity rate decreased from 4.7% and, 3.6% to 3.1%, and AUC were 0.79, 0.77, and 0.76, respec tively. The sensitivity/specificity of FIT 22, FIT 50, and FIT 100 for CRC were 61.9%/95.6%, 57.3%/96.7%, and 54.0%/97.1%, respectively, and their positive predictive value/negative predictive value were 7.0%/99.8%, 8.7%/99.8%, and 9.3%/99.8%, respectively. The number of colonoscopies needed to detect one CRC for FIT 22, FIT 50, and FIT 100 were 14.3, 11.6, and 10.8, respectively.
Conclusions
This study presents cut-off values for CRC screening to strike a balance between FIT performance and colonoscopy burden, which could provide information for the cut-off of FIT for CRC in a national cancer scre ening program.

Keyword

Colorectal neoplasms; Fecal immunochemical test; Colonoscopy; Colonoscopy burden; Cut-off value