Diagnostic value of immunochemical fecal occult blood test for small colorectal neoplasms.
This study was designed to assess the diagnostic value of an immunochemical fecal occult blood test for small colorectal adenomas. In a screening program based comparative study, 60 colorectal adenomas under 1 cm (small polyp group), 60 colorectal adenomas 1 cm or larger (large polyp group) and 60 colorectal cancers (cancer group) detected by occult blood screening, and 120 healthy controls (control group), served as subjects. Moreover, 50 small adenomas, 50 large adenomas and 50 cancers detected in out-patient clinics, and 100 controls, served as subjects of a hospital based comparative study. Each of these subjects was tested by an immunochemical occult blood with 3 consecutive days, after removal of these colorectal neoplasms in a screening program based study and before as well as after removal in a hospital based study, and the positivity rate of this test was evaluated among these four groups in the two comparative studies. The positivity rate in a screening program based study was 23% for small polyp group, 8% for large polyp group, 5% for cancer group and 6% for control group, respectively. Significant difference was noted between small polyp and cancer as well as control groups (p <0.01), and between small polyp and large polyp groups (p <0.05). In a hospital based study, however, there was no significant difference in the positivity rate among four groups. These results suggest that high proportion of small polyps detected by fecal occult blood test screening may not be associated with bleeding from adenomas but probably from another gastrointestinal pathology.
Abdul Fattah
A S
AS
Department of Public Health, Shinshu University School of Medicine, Asahi 3-1-1, Matsumoto 390, Nagano, Japan. afattah@gipac.shinshu-u.ac.jp
Nakama
H
H
Zhang
B
B
Uehara
Y
Y
Kamijo
N
N
Fujimori
K
K
D000236:Adenoma / Q000175:diagnosis; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D006801:Humans; D007124:Immunoenzyme Techniques; D009780:Occult Blood; D011237:Predictive Value of Tests