B-335 Analytical Performance of the Novel EQA Material for Fecal Immunochemical Test for Hemoglobin
Authors: Yamada M , Takehara S 
Published: October 2024

Abstract

Background
EQA (external quality assurance) program for FIT (fecal immunochemical test for hemoglobin) is performed in many countries, and its demand increases as FIT is widely used in organized colorectal cancer screening programs. The materials used in FIT EQA vary from buffer-based liquid control, and lyophilized stool, to material that mimics stool, artificial stool. We could not find ideal EQA material with hemoglobin uniformly contained, good stability of hemoglobin, and ease in use such as ready-to-use form. The merit to use material that simulates actual sample, stool, is not only to be compliant with ISO15189 but also to suit various methods and sampling devices in FIT. The development of artificial stool material has been awaited by laboratories using FIT to evaluate errors and precisions in specimen collection.We assessed the analytical performance of the new artificial stool developed in HECTEF (Health Care Technology Foundation) to evaluate this artificial stool material was suitable as an EQA material. We examined the following three points: 1) Sample collection, 2) Uniformity, and 3) Stability of hemoglobin.

Methods
1) Sample collection: The material was collected with the sampling probes of OC-Auto Sampling Bottle 3 (Eiken Chemical) and the collection amount was calculated by comparing the weight before and after sampling the artificial stool. 2) Uniformity: The uniformity of hemoglobin was evaluated during production before and after bottling based on “Uniformity of dosage units” section of The Japanese Pharmacopoeia 18th edition, 2021. The material was sampled from 10 different points and hemoglobin concentrations were measured using OC-Sensor DIANA. The uniformity of hemoglobin between the vials was evaluated by calculating the CV from the average of hemoglobin concentrations from samples of three points from three vials. 3) Stability of hemoglobin: The materials stored under different temperature conditions were compared with the material stored frozen at -20 °C. Storage conditions were at refrigeration for 20 months, at 30 °C for 1 month, and freeze-thawing for five times. Evaporation from the material was evaluated by weighing the samples before and after storage at 30 °C for 1 month.

Results
1) Sample collection: The material was collected with sampling probes and the collection amounts were 106% (compared to theoretical amount).2) Uniformity: Uniformity of hemoglobin during production was within the specification of “Uniformity of dosage units” section of the pharmacopoeias, acceptance value&lt;15.0. Uniformity of hemoglobin among three vials was within ±10% CV.3) Stability of hemoglobin: Stabilities of the material were all within ±10% from the control material (frozen) after storage at all temperature conditions. Evaporation from the material in a vial was below 1% at 30 °C storage for 1 month.

Conclusions
This artificial stool is suitable for EQA material because it is confirmed that it shows favorable analytical results in sample collection, uniformity, and stability of hemoglobin. The evaluation of this material in the EQA program to show its suitability was performed by Labquality. The result is reported in a poster at ADLM 2024.