Colorectal cancer screening in asymptomatic adults: Comparison of colonoscopy, sigmoidoscopy and fecal occult blood tests
Journal
Journal of the Formosan Medical Association
Journal Volume
101
Journal Issue
10
Pages
685-690
Date Issued
2002
Author(s)
Cheng T.-I.
Hong C.-F.
Cheng S.H.
Lin Y.-M.
Tso C.Y.
Huang A.T.
Abstract
Background and Purposes: Fecal occult blood tests (FOBT) and flexible sigmoidoscopy have previously been recommended for colon cancer screening. More recently, studies have recommended colonoscopy due to the high rates of advanced neoplasm not detected by FOBT and sigmoidoscopy. Previous studies of the effectiveness of colonoscopic screening in Taiwan were limited to families of patients with colorectal cancer screening in asymptomatic adults. Methods: Screening colonoscopies and FOBT were performed in asymptomatic adults enrolled in our health-screening program between January 1997 and December 2000. Advanced neoplasm was defined as the presence of a polyp larger than 1 cm, polyps with villous or severe dysplastic features, or cancer. The junction of the splenic flexure and descending colon was defined as the boundary of the proximal and distal colon, and it was presumed that the dital colon would be examined using sigmoidoscopy in all patients. Data on the prevalence of polyps, advanced neoplasm and cancer among different age groups were obtained. The results of chemical and immunologic FOBT were compared. The anatomic distributions of advanced neoplasm and cancer were analyzed. Results: A total of 7,411 colonoscopic examinations were included in the analysis. Advanced neoplasm were present in 93 examination (1.3%), including 16 cancers (0.2%). Chemical FOBT detected 20.2% of advanced neoplasms and 37.5% of cancers. Immunologic FOBT detected 48.3% of advanced neoplasms and 37.5% of cancers. If sigmiodoscopy had been performed in place of colonoscopy, 26.9% of advanced neoplasm and 12.5% of cancers would not have been detected. Conclusion: Colonoscopy can detect neoplastic lesion undetectable by FOBT and sigmiodoscopy in asymptomatic subjects. These results suggest that colonoscopy should be the method of choice in colon cancer screening.
Subjects
Colonoscopy; Colorectal neoplasms; Occult blood; Polyps; Sigmoidoscopy
SDGs
Other Subjects
adult; age; aged; article; blood analysis; cancer patient; cancer screening; chemical analysis; clinical examination; clinical feature; colon polyp; colonoscopy; colorectal cancer; controlled study; descending colon; diagnostic accuracy; diagnostic error; disease severity; family study; female; health program; human; immunological procedures; intermethod comparison; major clinical study; male; medical decision making; occult blood; pathological anatomy; prevalence; sigmoidoscopy; symptom; Taiwan; Adult; Aged; Aged, 80 and over; Colonoscopy; Colorectal Neoplasms; Female; Humans; Male; Mass Screening; Middle Aged; Occult Blood; Sigmoidoscopy
Type
journal article