A retrospective study of immunochemical fecal occult blood testing for colorectal cancer detection.
BACKGROUND
Colonoscopic examination is the common pathway for positive screening tests detecting colorectal lesions. We evaluated a specific, quantitative high-throughput automatic immunochemical fecal occult blood test (Auto iFOBT) method for colorectal cancer (CRC) screening and to determine its concordance with physician assessments informed by complete colonoscopy, the gold-standard technique for evaluation of the colonic mucosa.


METHODS
1200 CRC symptomatic patients were recruited for a retrospective investigation. Colorectal neoplasia were localized by colonoscopy and cancer outcomes were enumerated according to severity. In addition, stool samples were collected and analyzed by Auto iFOBT to derive sensitivity, specificity, and positive predictive value. Qualitative colonoscopy and Auto iFOBT results were correlated, as were cancer severities and quantitative hemoglobin concentrations.


RESULTS
Ninety-one patients were found positive for CRC; 50 mucosal, 20 submucosal, and 21 advanced. At standard cutoff, sensitivity was 60%, 90%, and 95%, respectively. Specificity and positive predictive value for all neoplasia and cancers were 89.6% and 86.4%, and 60.9% and 33.7%, respectively. Cancer severities could be approximated roughly according to hemoglobin concentrations.


CONCLUSIONS
Specific qualitative 2-day Auto iFOBT is an accurate tool for the detection of colorectal cancer and therefore provides the basis for a large-scale screening program.
Oono
Yasuhiro
Y
Department of Gastroenterology, National Cancer Center Hospital East, Chiba, Japan. doc2adova@yahoo.co.jp
Iriguchi
Yosuke
Y
Doi
Yosuke
Y
Tomino
Yasuhiro
Y
Kishi
Daisuke
D
Oda
Johji
J
Takayanagi
Satoshi
S
Mizutani
Masaru
M
Fujisaki
Tadashi
T
Yamamura
Akihiko
A
Hosoi
Tozo
T
Taguchi
Hiromi
H
Kosaka
Mieko
M
Delgado
Pabel
P
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003106:Colon / Q000378:metabolism / Q000473:pathology; D015179:Colorectal Neoplasms / Q000097:blood* / Q000175:diagnosis*; D055088:Early Detection of Cancer / Q000379:methods / Q000592:standards*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009780:Occult Blood; D012189:Retrospective Studies