Colonoscopic evaluation of immunochemical fecal occult blood test for detection of colorectal neoplasia.
OBJECTIVE
This study was carried out to assess the validity of three testing methods of immunochemical occult blood according to the number of collection times as a means for colorectal cancer screening.


METHODS
Four thousand six hundred and eleven asymptomatic individuals, who received both an immunochemical occult blood test with a three-day method and colonoscopy during a medical checkup, served as subjects for this study. For evaluation of the desirable number of sampling times, we used the results of the first day for the 1-day method, the results of the first and second days for the 2-day method, and the results of three-consecutive days for the 3-day method. Sensitivities and specificities of these three testing methods were evaluated.


RESULTS
Sensitivities and specificities for colorectal cancer were calculated to be 56% and 97% for the 1-day method, 83% and 96% for the 2-day method, and 89% and 94% for the 3-day method, respectively, showing a significant difference in sensitivity between the 1-day and the 2-day methods, as well as the 3-day method (p < 0.01), and in specificity between the 1-day as well as the 2-day and 3-day methods (p < 0.05).


CONCLUSIONS
These findings indicate that the immunochemical fecal occult blood test is useful for the diagnosis of colorectal cancer, and that 2-day testing is recommended as a means of screening for colorectal cancer.
Nakama
H
H
Department of Public Health, Shinshu University School of Medicine, Matsumoto, Japan.
Yamamoto
M
M
Kamijo
N
N
Li
T
T
Wei
N
N
Fattah
A S
AS
Zhang
B
B
D000236:Adenoma / Q000175:diagnosis*; D000328:Adult; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D005069:Evaluation Studies as Topic; D006801:Humans; D009780:Occult Blood; D012680:Sensitivity and Specificity