2018 Volume 67 Issue 3 Pages 328-333
The morbidity and mortality of colorectal cancer have been increasing yearly in Japan, and early detection and early treatment are the most important methods to reduce the mortality. In this study, we investigated the fundamental performance of HM-JACKarc®, an automated fecal occult blood test analyzer, which is a new system for measuring the amount of hemoglobin present in stool for screening. The coefficients of variation (CV) ranges were 0.6–1.6% for the within-run reproducibility and 3.6–5.2% for the between-run reproducibility. The lower limit was 4.0 ng/mL, and the satisfactory dilution linearity was obtained at 400 ng/mL. After measuring a solution with a theoretical hemoglobin concentration of 360,000 ng/mL, the first measurement of the 0 concentration sample did not exceed the cut-off value (30 ng/mL) in a carry-over examination. Although the results could not completely deny the effect of carry-over in abnormally high concentration samples, it is considered that this problem can be entirely avoided by, for example, the proper operation and utilization of the inspection system. In the prozone test, high sensitivity was obtained up to 400 ng/mL, which is the upper limit of measurement. A linear relationship with conventional equipment was obtained. The estimated regression equation was constructed as y = 0.957 − 0.421, the correlation coefficient was 0.995, and the agreement rate was 96.6%. The equipment was estimated to be useful for the screening for colorectal cancer, because the operation method is simple, and the measurement results can be reported quickly and accurately to the clinic in routine examination.
